1 University of Bologna, Bologna, Italy. 2 Université de Montpellier, Montpellier, France. 3 Deutsches Elektronen-Synchrotron DESY, Hamburg, Germany. 4 Wageningen University and Research, Wageningen, The Netherlands. 5 The University of Queensland, Brisbane, Australia.

Thallium (TI) is a relatively rare element, but highly toxic for all living organisms already at low concentrations. Some plant however evolved TI hyperaccumulation and the most extreme TI hyper-accumulator is *Biscutella laevigata* capable of attaining >32,000 µg TI g⁻¹ in its leaves. Interestingly, only some ecotypes have the ability to hyperaccumulate TI when growing on TI-rich soils. The study aims at understanding the TI handling mechanisms, tolerance and distribution in two ecotypes of *B. laevigata* using synchrotron-based X-ray fluorescence microscopy. Two *B. laeavigata* accessions were used in this study coming from: Les Malines (France, TI-hyper accumulator) and Feltre (Italy, non- accumulator). Both accessions were grown in aeroponics for two months and were subjected to three TI treatments: 0 (control), 5 and 30 µM. The two accessions showed morphological differences in terms of leaves shapes and trichome distribution, with Les Malines having deeply lobate leaves and scarce trichomes compared to Feltre with almost entire leaves and dense trichomes. Overall, Les Malines accession showed greater TI tolerance and accumulation, compared to Feltre, which did not survive in the 30 µM TI treatment. Feltre accession accumulated 125 µg TI g⁻¹ in old leaves (at 5 µM), whereas Les Malines accession had 1750 and 24,130 µg TI g⁻¹ in old leaves (at 5 and 30 µM respectively). The distribution of TI was similar in the two accessions. The synchrotron µXRF analysis revealed that TI is localised in the vacuoles of epidermal cells, especially in trichome basal cells. Thallium also occurs in solid crystalline deposits (3–5 µm in size, ~40 wt% TI) that are mainly found in guard cells of stomata and in foliar margins. Other studies need to be carried out including more accessions, and including transcriptomics to yield information on the genes and genetic pathways linked to the phenotypic variation in TI hyperaccumulation.

## S.12.5 Synchrotron elemental imaging for elucidating nickel distribution in hyperaccumulators tropical plant species from New Caledonia

Sandrine Isnard¹, Kathryn M. Spiers²,
Tanguy Jaffré¹,³, Dennis Brueckner², Sarah
C. Irvin⁴, Jan Garrevoet⁴, Peter D. Erskine⁵,
Vidiro Gei⁵, Emmanuelle Montargès-
Pelletier⁶, Bruno Fogliani⁷, Guillaume
Echevarria⁸, Antony van der Ent⁸,⁹

1 AMAP, Université Montpellier, IRD, CIRAD, CNRS, INRAE, Montpellier, France. 2 Deutsches Elektronen-Synchrotron DESY, Germany. 3 AMAP, IRD, Herbier de Nouvelle-Calédonie, Nouméa, New Caledonia. 4 Helmholtz-Zentrum Hereon GmbH, Germany. 5 Centre for Mined Land Rehabilitation, Sustainable Minerals Institute, The University of Queensland, Australia. 6 Laboratoire Interdisciplinaire des Environnements Continentaux, CNRS, Université de Lorraine, France. 7 Institut Agronomique néo-Calédonien, Equipe ARBOREAL, New Caledonia. 8 Université de Lorraine, INRAE, LSE, F-54000, Nancy, France. 9 Laboratory of Genetics, Wageningen University and Research, The Netherlands.

Following the discovery of hyperaccumulation syndrome, numerous species were discovered, of which Ni-hyperaccumulators are by far the most numerous. Over 400 plant species are currently known to be nickel hyperaccumulators, and about a quarter of this diversity is found in New Caledonia. The extremely high Ni concentrations found in hyperaccumulator species raise the question of how plants can survive with such high metal content in their cells, and how does plant diversity translate into Ni-location strategy within the plant. At particular, the exact localization of metal within the leaf is of central significance because it might interfere with metabolic process such as photosynthesis. In this talk, we present our current knowledge of Ni distribution in hyperaccumulators tropical plant species from New Caledonia, based on synchrotron elemental imaging. We then make of focus on Ni-enriched laticifer in the model species *Pycnandra acuminata* to bridge the gap between the structure and function of laticifers in metal accumulation. The extraordinarily high nickel concentrations in this species function as an effective natural tracer for both synchrotron-based X-ray fluorescence microtomography and phase contrast microtomography, allowing non-destructive probing of
<figure><img src="image_46.png" /></figure>

the structure and the physiological functioning of this unique duct system. Using fresh plant samples, we combined analysis with these techniques to visualize intact laticifers in vivo for the first time and further, to provide unprecedented insights in the distribution and structure of laticifers throughout the plant, from roots to leaves. Considering that laticifers extend from root-to-shoot, our study elicits the hypothesis that the laticifers network constitute an independent ion transport system, which would establish a new paradigm in long distance transport in plants.

### S.12.6 How to achieve a selenium-rich lifestyle in the barren Australian outback

Jeroen van der Woude¹, Maggie-Anne Harvey¹,² and Antony van der Ent¹,²,³

1 Laboratory of Genetics, Wageningen University and Research, Wageningen, The Netherlands. 2 Centre for Mined Land Rehabilitation, Sustainable Minerals Institute, The University of Queensland, Brisbane, Queensland, Australia. 3 Université de Lorraine, INRAE, LSE, Nancy, France

Selenium (Se) is formed in supernovae and is a rare component in most soils. Nevertheless, many organisms including *Homo sapiens* need selenium to produce selenocysteine (SeCys), also referred to as the 21st amino acid, required for synthesis of so-called selenoproteins. In contrast, land-plants lost the need for selen

lenium, likely due to a decreased bioavailability of Se over the last couple of million years. Interestingly, some plants have developed a selenophile lifestyle regardless, growing on selenium-rich soil toxic to most plants. Some of these plants such as *Neptunia amplexicaulis* hyperaccumulate selenium up to 1.3% of their dry mass. These high tissue Se levels normally cause severe oxidative stress and dysfunctional proteins due to inadvertent incorporation of SeCys en lieu of cysteine. The latter is caused by the chemical similarity of selenium to sulfur, leading to the production of various organic selenium compounds through the sulfur transport- and assimilation pathway, including SeCys and Selenomethionine. However, in the dry and saline Australian outback, *Neptunia amplexicaulis* manages to grow well on toxic soil and accumulate extreme concentrations of selenium in the plant tissue. Its sister-species *Neptunia heliophile* has also developed an increased tolerance to selenium, but rather excludes Se from its tissue instead of accumulating it. Our work aims to determine what mechanisms are necessary for the extreme lifestyles of *N. amplexicaulis* and *N. heliophila* and especially how to accumulate and tolerate high tissue selenium levels. This investigation involves the analysis of recently sequenced genomes of *N. amplexicaulis* and *N. gracilis* as well as full-length transcriptomics. Furthermore, this work involves the development of transformation protocols for *N. amplexicaulis* to get direct evidence of gene involvement in Se hyperaccumulation. The research outcomes could help improve crop Se content and thereby ameliorate the currently widespread Se-deficiency in various human populations.

## S.13 SYSTEMATICS, PHYLOGENETICS, BIOGEOGRAPHY AND EVOLUTION OF MELASTOMATACEAE

### S.13.1 A phylogenomic analysis of Melastomataceae: congruence and incongruence across genomes

Monique Romeiro Brito¹, Léo-Paul Dagallier², Marcelo Reginato³, Lucas F. Bacci¹, Nico

Cellinese¹, Gudrun Kadereit⁴,⁵, Renato Goldenberg⁶, Ling Liu⁷, Darin S. Penneys⁸, Marie Claire Veranso-Libalah⁴, Luo Chen⁴, Renchao Zhou⁷, Walter S. Judd¹, Fabián A. Michelangeli², Lucas C. Majure¹

1 University of Florida Herbarium, Florida Museum, Gainesville, FL, USA. 2 New York Botanical Garden, Bronx, NY, USA. 3 Universidade Federal de Rio Grande do Sul, Porto Alegre, RS, Brazil. 4 Ludwig-Maximilians-Universität München, Munich, Germany. 5 Botanischer Garten München-Nymphenburg, Munich, Germany. 6 Universidade Federal de Parana, Curitiba, PR, Brazil.
tiba, PR, Brazil. 7 Sun Yat-sen University, Guangzhou, China. 8 University of North Carolina-Wilmington, Wilmington, NC, USA

Melastomataceae is a megadiverse family, harboring almost 6000 species and distributed worldwide, mostly in the tropics. The monophyly of the family has been supported based on morphological and anatomical data through the last century. However, the advent of molecular phylogenies has helped to clarify the identification of new major clades within the family. Additionally, molecular phylogenies have also proven a challenging task to uncover relationships among major clades when using only a few sets of plastid and nuclear regions. The use of phylogenomic datasets in the family using target sequencing and plastome data has been shown to be a promising tool for obtaining robust phylogenetic relationships within this family. However, thus far phylogenomic studies have been focused on a limited taxon sampling and presented weakly supported nodes. Here we aimed to reconstruct a phylogenetic tree for Melastomataceae comprising 21 out of 23 tribes and almost 80 percent of the generic diversity. For this we relied on a Hyb-Seq approach, joining efforts from nuclear target sequencing and plastid genome skimming datasets. We reconstructed plastid, mitochondrial, and nuclear phylogenies using concatenated and coalescent approaches. While we recover fairly robust phylogenies and tribal composition congruent with previous analyses, the relationships and support recovered at some of the deeper nodes vary across genomes and analytical methods. We discuss sources of phylogenetic conflicts between approaches and genetic compartments. We suggest that incongruences are linked to deep/ancient events of introgression/duplication/reticulate processes of evolution.

### S.13.2 Pollination syndromes and pollinator shifts can be explained by climatic and elevational gradients

Constantin Kopper¹, Jürg Schönenberger¹, Agnes S. Dellinger¹

1 University of Vienna, Rennweg 14, Vienna, Austria.
Contact: constantin.kopper@univie.ac.at

Pollination syndromes are defined as suites of floral traits, which have evolved repeatedly across angiosperms in adaptation to distinct functional pollinator groups. The large, pantropically distributed family Melastomataceae is dominated by buzz-bee pollination (95.5%), where pollen is released from tubular, poricidal

anthers through vibrations. In seven (of 23) tribes, shifts to other syndromes have occurred. These shifts can be found in the New- and Old-World and have been shown to be correlated with increasing altitude in the Neotropics. We recorded 44 functional floral traits across 411 species, spanning the whole family. We used machine learning algorithms (random forest - RF) to identify pollination syndromes for species with documented pollinators and employed these trained models to predict pollinators for species without observations. We combined the results from the RF analyses with climatic and distribution data (elevation) to test if climatic variables and altitudinal gradients correlate with specific pollination syndromes and certain traits. Finally, we investigated if the same mechanisms apply for the New- and Old-World. Our results indicate strong support for four well differentiated pollination syndromes within Melastomataceae: "buzz-bee", "nectar-foraging vertebrate", "food-body-foraging vertebrate", and "generalist". Pollination syndromes in Melastomataceae can be discriminated by six system specific floral traits of which reward type and pollen release mechanism are the two most important traits. Climatic variables and altitude explain 67% of the variation found in Melastomataceae, with altitude having a particularly strong impact. Shifts away from the ancestral "buzz-bee" syndromes, which can be found along the whole elevational gradient but declines towards the top of the mountain, start to appear at about 1500m (except for the "generalist" syndrome - start at about 400m and goes up to 1800m). Also, shifts to the "nectar-foraging vertebrate" and "food-body-foraging vertebrate" syndrome are associated with cooler Temperatures. These patterns can be found in the New- and Old-World.

### S.13.3 Bridging evolutionary gaps: utilizing public and newly generated target capture data for the placement of some enigmatic old world

Marie Claire Veranso-Libalah¹, Luo Chen¹, Xander van der Burgt², Pepe Haba³, Peter Quakenbush⁴, Gudrun Kadereit¹,⁵

1 Systematik, Biodiversität & Evolution der Pflanzen, Ludwig-Maximilians Universität München, Germany. 2 Herbarium, Royal Botanic Gardens, Kew, Richmond, Surrey, UK. 3 Guinée Biodiversité, Conakry, Guinea. 4 Department of Biological Sciences, Western Michigan University, Kalamazoo, Michigan, USA.
<figure><img src="image_47.png" /></figure>

### 5 Botanischer Garten München-Nymphenburg, Munich, Germany

The strategic amalgamation of public and newly generated target capture data, utilizing the universal Angiosperms353 probe set and group-specific probe sets (e.g., Melastomataceae) and Sanger data have emerged as a potent strategies in phylogenetic studies. Through this synergistic integration, our aim is to unravel the evolutionary mysteries surrounding taxa that have never been sampled or placed in a phylogenetic context, to enrich our understanding of biodiversity and the tree of life. In recent years, efforts have been made to resolve phylogenetic relationships among OW Melastomataceae taxa. However, several enigmatic taxa, including *Dionychastrum schliebenii*, *Dissotis leonensis*, *Dissotis splendens*, *Feliciadamia stenocarpa*, *Medinilla mirabilis* and *Kendrickia walkeri*, persist as unplaced and/or unsampled in current taxonomic revisions and phylogenetic studies. With recent field collections of these taxa and the utilization of public and newly generated target capture data, our goal is to phylogenetically place all the aforementioned taxa. The resulting phylogenetic placement, complemented by morphology and anatomy, provides a clearer systematic picture and enhances our understanding of the evolution of Melastomataceae at large.

## S.13.4 Phylogenomics of the Merianieae (Melastomataceae) bring new perspectives for its systematics, biogeography and macroevolution

Léo-Paul Dagallier¹, Frank Almeda², Lucas Bacci³, Agnes S. Dellinger⁴, Diana Fernández-Fernández⁵, Robin Fernandez Hilario⁶, Renato Goldenberg⁷, Humberto Mendoza-Cifuentes⁸, Jhon S. Murillo-Serna⁹, Carmen Ulloa Ulloa¹⁰, Lucas C. Majure³, Fabián A. Michelangeli¹

1 New York Botanical Garden, Bronx, NY, USA. 2 California Academy of Sciences, San Francisco, CA, USA. 3 University of Florida, Gainesville, FL, USA 4 University of Vienna, Vienna, Austria. 5 Instituto Nacional de Biodiversidad, Quito, Ecuador. 6 CORBIDI, Lima, Perú. 7 Universidade Federal do Paraná, Curitiba, PR, Brazil. 8 Jardín Botánico de Bogotá, Bogotá, DC, Colombia. 9 Universidad de Antioquia, Medellín,

Antioquía, Colombia. 10 Missouri Botanical Garden, Saint Louis, MO, USA

The tribe Merianieae (Melastomataceae) is a group of trees, lianas and herbs distributed in the American tropics. It contains ca. 288 species within 7 genera. The tribe is distributed in both lowland and highland rainforests, from southern Mexico and Central America, the Greater Antilles to the Central Andes, and eastwards to the Atlantic rain forest. We present the most up-to-date phylogenetic reconstruction of the tribe based on phylogenomic sequence data, including 184 species (ca. 64%) and hundreds of nuclear loci. We used different phylogenetic reconstruction approaches including paralogy resolution steps, and secondary calibration to date the tree. Phylogenetic results are consistent with previous studies based on Sanger sequence data, but phylogenetic placement of some clades (*Adelobotrys*, *Macrocentrum*, *Salpinga*) remains problematic. Indeed, we recovered many gene tree conflicts at both deep and shallow nodes in the Merianieae phylogeny and relate them to reticulate processes of evolution, possibly linked to introgression and rapid radiations. *Macrocentrum* is not monophyletic and recovered in three clades. *Meriania* likewise is not monophyletic, because one group (*Adelbertia*) is more closely related to *Adelobotrys*, and *Axinaea* is embedded within the remaining *Meriania*. *Graffenrieda* and *Centronia* form a well-supported clade. The group seems to have originated in the Guiana Shield, but most of the diversity is in the Andes, as a result of two distinct radiations (one in *Graffenrieda* and one in *Meriania*). Secondary radiations also occurred in the Guayana Shield and the Atlantic Forest. We discuss the impact of the Andes in generating the diversity and the biogeographic history of the clade.

## S.13.5 A synopsis of the genus Sonerila Roxb. (Melastomataceae: Sonerileae) in India

Resmi Sekarathil¹,², Nico Cellinese³, K. Karthigeyan² & Santhosh Nampy¹,

1 Department of Botany, University of Calicut, Kerala, India. 2 Botanical Survey of India, Southern Regional Centre, Tamil Nadu, India. 3 Florida Museum of Natural History, University of Florida, Florida, USA

Sonerila Roxb., a taxonomically complex genus in the family Melastomataceae, comprises approximately 180 taxa, and as one of the largest groups in Asia, it is distributed mainly across Sri Lanka, India, Nepal, Bhutan, South China, Taiwan, In-
<figure><img src="image_48.png" /></figure>

do-China and the Malay Archipelago. The genus is represented by caulescent and acaulescent herbaceous plants of shady habitats. It is easily recognized by its generally trimerous flowers, mostly uniparous (scorpioid) cymes, and 3-locular, inferior ovary. *Sonerila* is the largest genus in the tribe Sonerileae in India, with 49 species and one variety, including a substantial percentage of endemics. The Western Ghats region indeed stands out as a hotspot for *Sonerila* with 43 species and one variety, an astonishing 86% of which are exclusive to this particular biogeographic zone. This remarkable richness of species serves as a clear indication of adaptive radiation and explosive evolution within the genus making it an intriguing subject of study in the realm of Melastomataceae systematics and evolution. The present study highlights the diversity of *Sonerila* in India with a revisionary account including key for the identification, detailed descriptions, notes on infraspecific variations, geographical distribution, and conservation status assessment. Six species were found new to science. Nomenclatural issues relevant to the taxonomic study were also resolved, resulting in subsequent synonymy, reinstatement of names, and typifications.

## S.13.6 Neotropical depauperons: from neglected small genera to strategically placed clades in Melastomataceae phylogenetic trees

Renato Goldenberg¹, Bruno Bastos¹, Lucas F. Bacci¹,², Thuane Bochorny³, Marcelo Reginato⁴, Fabian A. Michelangeli⁵

1 Universidade Federal do Paraná, Curitiba, Brazil. 2 Universidade Federal de Santa Catarina, Florianópolis, Brazil. 3 Instituto de Pesquisas Jardim Botânico do Rio de Janeiro, Brazil. 4 Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil. 5 Institute of Systematic Botany, The New York Botanical Garden, USA

Asymmetric patterns in species richness are a notable feature across different lineages and geographic regions. While some lineages are rich, diverse, and widely distributed, the "depauperons" are phylogenetically isolated, with only one or a few narrowly distributed species. Recent phylo-

genetic studies of Melastomataceae resulted in a new classification with both megadiverse lineages, such as tribes Miconieae (1900 species), Sonerileae (1100) and Melastomateae (820) and groups with few species, such as Lithobieae (1), Rupestreeae (2), Stanmarkieae (4), and Eriocnemeae (7) in the Neotropics, and Dinophoreae (8) and Feliciadameae (1) in Africa. These depauperon tribes have been very recently described, with their taxa traditionally placed in bigger tribes, even though they presented features uncommon for those groups or even the whole family. Three of these groups are restricted to Eastern South America: Lithobieae grows on rock crevices, and is sister to Pantropical Henrietteae+Astronieae (250 spp); Rupestreeae grows in "campos rupestres", and is nested in Pantropical Melastomatae+Dinophoreae+Rhexieae (850); Eriocnemeae's 3 genera grow in rainforest, iron ore outcrops, and montane vegetation, and are sister to Neotropical Miconieae (1900). The recognition and inclusion of these depauperons in phylogenetic analyses is critical to the study of biogeography, character evolution and ecology of their speciose sister groups. The different patterns found for depauperons and their relatives may be explained by different speciation/extinction rates, but also by other traits. Overall, the species in these groups have limited dispersal ability, dependency on water for dispersal, and restricted niches. Climatic niche spaces of the depauperons are limited but included within the niche space of the sister tribes. The threat level for them can be exacerbated by climate change, mainly due to their inability to spread over long distances, restricted niches and increased habitat fragmentation. Future conservation actions should prioritize these unique taxa in Melastomataceae, especially under a phylogenetic diversity perspective.
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# S.14 A CONTINENTAL SCALE CONSORTIUM APPROACH TO BUILDING GENOMICS CAPACITY AND RESOURCES: GENOMICS FOR AUSTRALIAN PLANTS. SESSION 1

## S.14.1 A consortium approach to building the Australian Angiosperm Tree of Life.

Lalita Simpson¹, Darren M. Crayn¹,
Theodore R. Allnutt², William J. Baker³, Matt
Barrett¹, Gillian Brown⁴, Félix Forest³, Chris
Jackson², Paul J. Kersey³, Mabel Lum⁵,
Olivier Maurin³, Todd G. B. McLay⁶, Daniel
J. Murphy², Katharina Nargar¹, Hervé
Sauquet⁷, Alexander Schmidt-Lebuhn⁸,
Kelly A. Shepherd⁹, Michelle Waycott¹⁰

1 Australian Tropical Herbarium, James Cook Uni-
versity, Smithfield, Australia. 2 Royal Botanic Gar-
dens Victoria, Melbourne, Australia. 3 Royal Botanic
Gardens, Kew, Richmond, UK. 4 Queensland Her-
barium, Toowong, Australia. 5 Bioplatforms Aus-
tralia, Sydney, Australia. 6 National Biodiversity DNA
Library, CSIRO, Parkville, Australia. 7 Botanic Gar-
dens of Sydney, Mt Annan, Australia. 8 Centre for
Australian National Biodiversity Research, Canber-
ra, Australia. 9 Western Australian Herbarium, Perth,
Australia. 10 State Herbarium of South Australia, Ad-
elaide, Australia

The Genomics for Australian Plants (GAP) Initiative, catalysed by Bioplatforms Australia in partnership with researchers from the Australian State and National Herbaria and Botanic Gardens, aims to develop genomics resources to enhance our understanding of the evolution of the Australian flora and support its conservation. GAP Phylogenomics, one of three GAP projects, has the long-term goal of resolving the Australian Angiosperm (flowering plant) Tree of Life (AATOL) to species level. To date, this inclusive project has brought together over 70 Australian researchers and herbarium staff and partnered with the global Plant and Fungal Trees of Life project (PAFTOL) to complete AATOL Stage 1 – a phylogenetic tree including at least one species exemplar of nearly 95% of Australian native angiosperm genera sequenced for a common set of hundreds

of nuclear markers (using the Angiosperms353 tar-
get capture baits). From the outset, data quality and
reusability have been a priority, ensured through
mandating rigorous documentation of comprehen-
sive sample metadata (e.g. identity, voucher, Na-
goya compliance, etc.). We show, through discus-
sion of its successes and challenges, the value of
a multi-institutional consortium approach and the
enablers such as well-curated collections and na-
tional collaborative research infrastructure, leading
to substantial increase in capacity and delivery of
biodiversity knowledge outcomes. Future directions
for the AATOL project will be discussed.

## S.14.2 Cross-platform and containerised phylogenomics-bioinformatics pipelines for sequence capture data: hybpiper-nf and paragone-nf

Alexander N. Schmidt-Lebuhn¹, Chris
Jackson², Todd McLay³

1 Centre for Australian National Biodiversity Research (a joint venture of Parks Australia and CSIRO), Canberra, Australia. 2 Royal Botanic Gardens Victoria, Melbourne, Australia. 3 CSIRO, Melbourne, Australia

The phylogenomics activity of the Genomics for Aus-
tralian Plants consortium uses target capture / en-
richment data. Early in the process, a phylogenom-
ics-bioinformatics working group was established to
evaluate options for the consortium's technical ap-
proach ranging from the desired sequencing depth
across assembly to the phylogenetic analysis itself.
In terms of the analysis pipeline, paralogy was identi-
fied as a key concern because phylogenetic analyses
were going to be conducted both at the scale of all
angiosperms and in selected genera and plant fam-
ilies known to be characterised by ancestral genome
<figure><img src="image_50.png" /></figure>

duplication events. We adapted the well-established HybPiper software for sequence assembly and paralog discovery, and a collection of previously published scripts for the inference of ortholog groups from gene tree topologies. We iteratively built an integrated workflow in which the HybPiper outputs were provided in a format directly usable for ortholog inference, discovered and fixed bugs, and added alternative options for several steps such as assembly, alignments, and gene tree inference. The resulting pipelines have been published as two Nextflow scripts with a Singularity container providing all dependencies to allow easy installation independent of platform, hybpiper-nf and paragone-nf, and recently also as Python packages that can be installed with conda. We discuss the history of their development, the principles behind the analyses, and important options available to the user.

## S.14.3 Phylogenomics, continental biogeography and climate-dependent diversification of Australian Chamelaucieae (Myrtaceae)

Francis J. Nge¹,², Barbara Rye³, Peter Wilson¹, Kevin R. Thiele⁴, Ed Biffin²,⁵, Michelle Waycott²,⁵, Korjent van Dijk⁵, Matthew Barrett⁶

1 National Herbarium of New South Wales, Botanic Gardens of Sydney, Australian Botanic Garden, Locked Bag, Mount Annan, NSW, Australia. 2 School of Biological Sciences, Faculty of Science, Adelaide, SA, Australia. 3 Western Australian Herbarium, Department of Biodiversity, Conservation and Attractions, Locked Bag 104, Bentley Delivery Centre, Western Australia, Australia. 4 School of Biological Sciences, the University of Western Australia, Australia. 5 State Herbarium of South Australia, Botanic Gardens and State Herbarium, Adelaide, SA, Australia. 6 Australian Tropical Herbarium, Sir Robert Norman Building, James Cook University Cairns Campus, McGregor Road, Smithfield, Qld, Australia

The Myrtaceae tribe Chamelaucieae is a diverse tribe predominantly distributed across Australia with over 660 species across 34 genera. The phylogenetic backbone of this tribe was previously unresolved based on studies utilising Sanger sequencing data. Here, we present an updated well-resolved phylogeny of the tribe as part of the GAP Stage 2 initiative, utilising over 400 nuclear single-copy loci (angio353 and Ozbaitis).

Ten out of the 11 subtribes with 33 out of the 34 genera are represented in our study. We dated the phylogeny using secondary calibrations and looked at biogeographic disjunctions across different Australian biogeographic regions using BioGeoBEARS. We also tested for environmental-dependent diversification using RPANDA. Findings from our biogeographic analyses indicate a mixture of vicariance and dispersal events across different simulated climatic scenarios (e.g., aridification of Australia since the Miocene). Biogeographic results and speciation decline detected from our phylogeny coinciding with the Eocene-Oligocene extinction event (33 Mya) will also be discussed.

## S.14.4 Acacia phylogenomics using the Angiosperms353 target capture bait set

Daniel J. Murphy¹, Bruce Maslin², Theodore Allnutt¹, Todd McLay³

1 Royal Botanic Gardens Victoria, Melbourne, Victoria, Australia 2 Western Australian Herbarium, Kensington, Western Australia, Australia 3 National Biodiversity DNA Library, National Collections and Marine Infrastructure, CSIRO, Parkville

Acacia – Australia's largest genus of flowering plants – was selected for a Genomics for Australian Plants (GAP)-supported phylogenomic analysis using the Angiosperms353 target capture bait set. While Sanger amplicon sequencing datasets have previously been compiled for approximately 50% of Acacia species, those datasets comprised fewer than 10 markers and lacked phylogenetic resolution in certain parts of the tree, demonstrating the need for a deeper phylogenomic-based sampling of the Acacia genome in order to resolve the phylogeny with greater support. In this talk, results are presented of an initial phylogenomic analysis of around 10% of the total number of Australian Acacia species, sequenced for the Angiosperms353 target capture baits and representing all major evolutionary lineages of Acacia that had previously been discovered in molecular phylogenies and morphological classifications. Initial phylogenetic analyses, including appropriate mimosoid legume outgroups and using several analytical approaches, have revealed congruence in the major clades that were previously discovered, such as the Pulchelloidea clade, which unites morphologically disparate taxa from several traditional sections in Acacia. When compared to the topologies found in previous molecular phylogenetic studies, the overall
<figure><img src="image_51.png" /></figure>

phylogenomics-based topology is somewhat different, which may be due to increased phylogenetic resolution of the markers or differences in the targeted sampling of species in particular parts of the tree. Some novel clades, including a sister clade to the majority of Acacia species, are recovered in our analyses. Due to the level of support for relationships, in combination with the very high success rates for sequencing of silica-dried and older herbarium samples, the Angiosperms353 bait set shows great potential as the basis for a larger-scale study of Acacia species, with the ultimate aim of generating a new formal classification of the genus.

**S.14.5 Using sequence capture to look beyond floral symplesiomorphies and classify two new genera in the Australian Rutaceae (Sapindales)**

Harvey K. Orel¹, Todd G. B. McLay², Paul I. Forster³, Michael J. Bayly¹

1 School of BioSciences, The University of Melbourne, Parkville, Victoria, Australia. 2 National Biodiversity DNA Library, NCMI, CSIRO, Parkville, Australia. 3 Queensland Herbarium, Department of Science, Information Technology and Innovation, Brisbane Botanic Gardens, Toowong, Queensland, Australia

Taxonomists have relied heavily on floral characters to group taxa and assess relationships, despite the adaptive significance of these characters and their correlation with pollination modes. Even if the taxonomist, wary of misinterpreting homology, choos-

es to account for the instability of floral characters, there may not be sufficient morphological characters outside of these to make useful inferences. This is especially problematic in groups with numerous instances of separate floral specialisation, where interpreting which characters are symplesiomorphic is difficult. The *Eriostemon* group (Sapindales: Rutaceae) includes 16 genera and ~209 species that almost all occur naturally in Australia (with ~12 spp. in 3 genera outside of Australia). The group is most diverse in the south-east and south-west of Australia where species most commonly occur in eucalypt-dominated woodlands and forests, but are also found in rainforests, savanna, coastal and montane heathlands, semi-arid scrub and desert shrubland. Morphologically, members of the group vary in habit, leaf phyllotaxy, fruit type and, most notably, floral characters. Pollination syndromes vary between and within genera, with a predominant contrast between flowers that are borne upright with spreading, open petals and flowers that are pendent and tubular or aggregated into inflorescences surrounded by large or colourful bracts. This diversity has resulted in taxonomic legacy of large genera with unspecialised, open petalled flowers, and small or monotypic genera with more complex flowers. We present results from a phylogenomic study of the *Eriostemon* group based on target capture sequencing using the Angiosperms353 kit. Our results reveal the extent to which the genus *Philotheca* (54 spp.) is polyphyletic and highlight how the current classification of that genus is based on symplesiomorphic floral characters. They provide new insight into shifts in pollination modes across the group and support the recognition of two new genera, separated from *Philotheca*.

**S.15 EVOLUTIONARY ECOLOGY OF PLANTS.**
**SESSION 1**

**S.15.1 Pre-dispersal seed predation as a selective force on plant mating system and reproductive traits**

Gaku Kudo, Akari Shibata¹

1 Faculty of Environmental Earth Science, Hokkaido University, Sapporo, Japan

Not only mutualistic plant-pollinator interactions but also antagonistic plant-herbivore interactions can be a selective force on sex allocation in angiosperms. The present talk addresses how predispersal seed predation affects the reproductive success and floral gender of andromonoecious herbs on a natural snowmelt gradient. The developing fruits of an alpine herb (*Peucedanum multivittatum*: Apiaceae) were intensively predated by a specialist lepidopteran larvae (*Phaulernis fulviguttella*: Epermeniidae) in the
<figure><img src="image_52.png" /></figure>

early-snowmelt habitat, where flowering occurred from mid to late July. In the late-snowmelt habitat, where flowering occurred after early August, seed predation was negligible because the oviposition of the predator moths was concentrated in early summer. The moths tended to oviposit on umbels with more perfect flowers and taller stems, whereas the number of male flowers was independent of their oviposition preference. Plants having male-biased umbels and short floral stems were prevalent in the early-flowering population, where plants suffered from intensive predation damage. The proportion of perfect flowers increased in the later flowering populations. The contribution of perfect flowers to intact fruit production was small when flowering occurred early in the season, and it consistently increased with the lateness of flowering period along the snowmelt gradient. Fitness measurements in the early-flowering population revealed that the production of many perfect flowers resulted in lower female fitness due to intensive seed predation. In contrast, male fitness as a pollen donor increased with total flower production irrespective of the composition of perfect and male flowers. Taken together, the greater production of male flowers at the expense of perfect flowers is advantageous under intensive predation pressure owing to the mitigation of predation damage with keeping the siring success. These results revealed that predispersal seed predation acts as a selective force that promotes male-biased sex allocation in andromonoecious plants.

## S.15.2 Constraints on the evolution of floral lifespan in a mixed-mating biennial

Rachel B. Spigler¹

1 Temple University, Philadelphia, PA, USA

Angiosperms display a brilliant diversity of floral forms, with striking variation in color, size, and scent, and morphology, including elaborate or specialized structures offering protection or rewards. Floral longevity, the length of time a flower remains open and functional, shows similarly impressive variation across species, ranging from a day or less to over a month, but by comparison has been largely overlooked. Consequently, even though floral longevity should strongly influence fitness by setting a critical time limit on opportunities for each flower to export and receive pollen, we lack a firm understanding of the forces that shape, maintain, and constrain vari-

ation in floral longevity. In fact, we even lack basic studies on the heritability of this trait in wild species. *Sabatia angularis* (Gentianaceae) is a mixed-mating biennial with remarkable intraspecific variation in maximum floral longevity, ranging from plants that produce flowers lasting only 5 days to those with flowers that can last over 20 days within a single population. I present data from a combination of field and greenhouse studies that characterize factors maintaining or constraining this variation, highlighting the importance of heritability, trade-offs, functional and ecological constraints, and plasticity.

## S.15.3 The conflict between ant protection and buzz-pollination mutualisms across angiosperm evolution

Amanda V. da Silva¹, Marjorie G. Weber², Anselmo Nogueira¹, Thais N. Vasconcelos², Avery Russell³, Tamiris D. Lima⁴, Lilian F. Melo⁵, Laura C. Leal⁶

1 Center of Natural and Human Sciences, Federal University of ABC, São Bernardo do Campo, Brazil.

2 Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, USA. 3 Department of Biology, Missouri State University, Springfield, USA. 4 Department of Botany, São Paulo State University, Botucatu, Brazil. 5 Department of Ecology, Conservation and Biodiversity, Federal University of Uberlândia, Uberlândia, Brazil. 6 Department of Ecology and Evolutionary Biology, Federal University of São Paulo, São Paulo, Brazil.

Mutualistic interactions involve varying degrees of conflicts, including the interference between different types of mutualism. One common interference occurs between protective ants and pollinators in plants bearing extrafloral nectaries (EFNs). While patrolling the plant, ants can reduce herbivory but also repel pollinators, especially bees. Since this conflict can affect plant reproductive performance, it might be selectively disadvantageous for plants to have both traits associated with ant defense and specialized bee pollination. Although conflicts in mutualisms have been extensively studied on the ecological scale, the evolutionary consequences of traits mediating interactions have not been considered. We hypothesize that there is a negative evolutionary correlation between traits mediating plant protection by ants and exclusive pollination by bees as
<figure><img src="image_53.png" /></figure>

in buzz pollinated plants. For that, we used a phylogenetic comparative approach, mapping all angiosperms reported to bear EFN associated with ant attendance and poricidal anthers associated with buzz pollination in an angiosperm tree comprising ca. 8,000 genera. We found that EFNs occur in 755 genera while poricidal anthers occurs in 544. However, only 45 plant genera have both traits. Moreover, we found a negative evolutionary correlation between EFNs and poricidal anthers, supporting our hypothesis that the interference of one mutualism in another can affect the evolutionary trajectory of the traits driving these interactions. This result means plants protected by ants are less likely to be involved in buzz pollination, or vice-versa, throughout angiosperm diversification. Altogether, our results evidenced that protective and pollination mutualisms may exert a reciprocal selective force that reduces the likelihood of the simultaneous occurrence of both ants and bee partners across angiosperm evolution. This emphasizes that we studies focused on the evolution of mutualistic traits should consider the joint effect of simultaneous mutualistic interactions instead of evaluating the traits related to different mutualisms separately.

## S.15.4 Convergence in carnivorous pitcher plants reveals a mechanism for composite trait evolution

Guillaume Chomicki¹

1 Durham University, Department of Biosciences, South Road, Durham, UK.

Complex, composite traits involve multiple components that, only when combined, gain a new synergistic function. Thus, how they evolve remains a puzzle -- what Darwin referred to as a 'special difficulty' in the Origin of Species. I present the results of multi-disciplinary study (Chomicki et al., 2024) that combined field experiments in the field and in the lab, microscopy, chemical analyses and laser Doppler vibrometry with comparative phylogenetic analyses to show that two carnivorous Nepenthes pitcher plant species independently evolved similar adaptations in three distinct traits to acquire a new, composite trapping mechanism. Phylogenetic comparative analyses suggest that this new trait arose convergently via 'spontaneous coincidence' of the required trait combination, rather than directional selection in the component traits. Our results indicate

a new mechanism for composite trait evolution and highlight the importance of stochastic phenotypic variation as a facilitator of evolutionary novelty. References: G Chomicki, G Burin, L Busta, J Gozdzik, R Jetter, B Mortimer, U Bauer (2024) Convergence in carnivorous pitcher plants reveals a mechanism for composite trait evolution. *Science* (In press).

## S.15.5 Lower mate availability and leakier self-incompatibility in Argentina anserina populations with small effective population size

Anita Cisternas-Fuentes¹,², Matthew Koski².

1 Departamento de Botánica, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción, Chile. 2 Department of Biological Sciences, Clemson University, Clemson, SC, USA

Achieving reproductive success in self-incompatible (SI) populations can be difficult. Flowers must receive enough pollen to produce seeds, and that pollen must be genetically compatible. The lack of available mates can reduce population-level reproductive fitness, have negative impacts on population growth, and increase extinction risk. The effects of low mate availability are exacerbated in small populations, which often harbor fewer S-alleles. So, even with substantial pollination, reproduction may fail. The breakdown of SI systems, however, may rescue population declines. Evaluating mate availability across populations can help us to understand the factors and conditions leading to mate limitation. We tested the predictions that populations with small effective population size have reduced mate availability and exhibit signatures of a breakdown in their SI mechanism. Additionally, we evaluated mechanisms at the pollen-pistil interface that contribute to the failure of outcrossed flowers and success of self-pollinated flowers. We performed self and outcross pollinations in 13 populations of Argentina anserina with known genomic estimates of effective population size to estimate mate availability and the SI index, and used fluorescence microscopy to enumerate pollen deposition, germination, and tube extension. Results show that genetically depauperate populations have reduced mate availability but not a lower SI index. Unsuccessful outcrosses did not receive fewer pollen grains or have lower pollen germination than suc-
<figure><img src="image_54.png" /></figure>

cessful ones. Barriers to outcross fertilization occurred in the style, specifically pollen tubes were arrested at the S-allele recognition site. Pistils from self-crosses showed that a higher proportion of self-pollen grains extend tubes past the location of the SI mechanism in the style in effectively smaller populations. However, this does not necessarily result in seed production. Results highlight strong mate limitation in genetically small populations of *A. anserina* and suggest that leaky-SI in small populations may represent early stages of a breakdown in SI.

## S.15.6 Fire-stimulated flowering: the effect of fire on pollination success in Mediterranean geophytes

Julia Gegunde¹, María Clara Castellanos ², Juli G. Pausas¹

1 Centro de Investigaciones sobre Desertificación (CSIC), Valencia, Spain. 2 University of Sussex, UK.

Fire-stimulated flowering is a widely recognized strategy in fire-prone ecosystems, such as Mediterranean ecosystems. Species with this strategy flower more profusely in postfire conditions than in absence of fire. We hypothesize that higher flowering density and less competition for pollinators could improve pollination success of plants that flower quickly after fire. We studied geophytes in Southern Spain and compared flowering in recently-burned areas with flowering in adjacent unburned areas. We performed pollinator censuses, estimated pollen grain deposition on the stigmas and counted fruit and seed production. We found that pollination rates and pollinator composition changed in burned areas compared to unburned areas. Individuals in burned areas showed higher pollen deposition on their stigmas and fruit and seed production was also higher in burned areas.

## S.16 BOTANICAL CONTRIBUTIONS FROM THE BIODIVERSITY HERITAGE LIBRARY

### S.16.1 Data for botany: unlocking the world of plants in the Biodiversity Heritage Library

Martin R. Kalfatovic¹

1 Biodiversity Heritage Library, Smithsonian Libraries and Archives, Washington, USA

The Biodiversity Heritage Library (BHL) is the world's largest open access digital library for biodiversity literature and archives. Headquartered at Smithsonian Libraries and Archives (SLA), BHL is a global consortium of research institutions working together to build and maintain a critical piece of biodiversity data infrastructure. Created in 2006 as a direct response to the needs of the taxonomic community for access to early literature, BHL provides free access to over 61 million pages of biodiversity content from the 15th-21st centuries. BHL provides a global community with ready access to a vast body of botanical literature. BHL works with the biodiversity community to develop tools

and services to facilitate greater access, interoperability, and reuse of content and data. Through taxonomic intelligence tools developed by Global Names Architecture, BHL has indexed more than 230 million instances of taxonomic names throughout its collection, allowing researchers to locate publications about specific taxa. BHL also works to bring historical literature into the modern network of scholarly research by retroactively assigning DOIs (digital object identifiers) and making this historical content more discoverable and trackable. Biodiversity databases such as the Catalogue of Life, International Plant Names Index, Tropicos, World Register of Marine Species, iNaturalist, and more rely on literature housed in BHL. To make this data FAIR (findable, accessible, interoperable, and reusable), BHL and its partners are working on a data pipeline to transform textual content into actionable data that can be deposited into data aggregators such as the Global Biodiversity Information Facility (GBIF). This paper provides an overview of BHL's botanical content.
<figure><img src="image_55.png" /></figure>

## S.16.2 BHL Australia: unlocking the foundation of Australia's botanical knowledge

Nicole Kearney¹

1 Biodiversity Heritage Library, Australia

The Australian node of the Biodiversity Heritage Library (BHL) began operation in 2010 with just one organisation, Museums Victoria. Since then, it has grown considerably. BHL Australia is now a national consortium with over 50 organisations contributing content to BHL. These organisations include all of Australia's state museums and herbaria, as well as universities, government agencies, royal societies, field naturalist clubs and natural history publishers. Together these organisations have made over 550,000 pages of Australia's biodiversity heritage freely accessible online. This paper focuses on the botanic knowledge contained within the BHL Australia collection, showcasing highlights from the 1600s through to the current year. It also celebrate the close relationship between BHL and the Australian botanical community. BHL Australia's active digitisation operation prioritises requests, which are received regularly from researchers, librarians, artists, educators, and policy makers. These have resulted in the rapid digitisation of historic literature essential to botanists, such as those studying the impact of Australia's devastating 2020 bushfires on endangered species. Finally, this paper presents BHL Australia's leading role in BHL's global efforts to bring the historic literature into the modern linked network of scholarly research. At the onset of the COVID-19 pandemic, BHL Australia pivoted from digitising historic literature to generating historic article data, mobilising both volunteers and staff to make the contents of our historic journals searchable. Since then, we've worked closely with the publishers of botanical journals (in Australia and around the world) to assign DOIs (Digital Object Identifiers) to their back issues. Many have elected to have BHL assign DOIs to their current issues as well. These DOIs are now appearing seamlessly in new publications, taxonomic databases, social media, and Wikipedia, providing instant, permanent, and persistent open access to the primary literature, the foundation of our knowledge of biodiversity.

## S.16.3 Amplifying the contribution of women to botany: an analysis of plant genera that were named after women

Carmen Ulloa Ulloa¹, Sabine von Mering², Lauren Gardiner³, Sandra Knapp⁴, Heather Lindon⁵, Siobhan Leachman⁶, Sarah Vincent⁴, Maria S. Vorontsova⁵

1 Missouri Botanical Garden, St. Louis, United States of America. 2 Museum für Naturkunde, Leibniz Institute for Evolution and Biodiversity Science, Berlin, Germany. 3 Cambridge University Herbarium, Cambridge, UK. 4 Natural History Museum, London, UK. 5 Royal Botanic Gardens Kew, Richmond, UK. 6 Independent researcher, Wellington, New Zealand

There are several thousand flowering plant genera named for people of all sorts, but those named for men outnumber – by more than 10 to 1 – those named for women. In mid-2021, a discussion on social media led to the formation of the multidisciplinary international working group to answer a simple question: how many plant genera honor women? More than two years of mostly virtual interaction, and additional research questions, resulted in the compilation of a new open dataset of 728 flowering plant genera honoring women or female beings (mythological). Some 36% honor mythological beings, and Medusa had six genera named after her, more than any real woman! We verified all these genera by examining original literature (the majority of which are freely available on the Biodiversity Heritage Library), and have categorized the honorees by profession, status or relationship to the describer. As part of the project, we created or updated Wikidata items for each of these women and genera; we worked closely with IPNI, Tropicos® and BHL receiving and providing feedback and data. Our motivation for the development of this dataset was not only to highlight names of plant genera that honor women, but also to enrich and bridge this information with data that would allow the names, roles, and lives of these women – many with fascinating stories –, to be shared more widely with others, both researchers and data sources like Wikidata. Amplification of the contributions of women to botany through multiple means will enable the community to better recognize and celebrate the role of this particular marginalized group in the history and development of science, their contributions to art, and natural history collections.
<figure><img src="image_56.png" /></figure>

### S.16.4 Right on Kew: BHL at the Royal Botanic Gardens

David Iggulden¹

1 Royal Botanic Gardens, Kew, London, UK

17 years on from its official formation, the Biodiversity Heritage Library's role continues to evolve, further increasing its relevance and demonstrating the collaborative resiliency of the consortium overall. BHL's global partnership of natural history, botanical and national libraries work together to develop the library and digitise their collections and make them freely available in BHL. As of November 2023, BHL has a total of 42 partners consisting of 19 Members and 23 Affiliates. As a Founder Member of the original project, the Royal Botanic Gardens, Kew has been a key member from the outset and is well placed to support the next stages of the resource's development. Kew's involvement with BHL provides an interesting case study overall, which illustrates how the BHL directly supports botanical research both within the organisation and across the globe. BHL provides an invaluable resource for work on plant nomenclature at Kew and has been a key partner in recent projects within both the Library and Archives and Economic Botany collections. BHL data is also being used to support the development of open science tools for taxonomy. It is for these reasons, plus the ongoing use by taxonomists that Kew continues to view BHL as essential to its mission to understand and protect plants and fungi for the well-being of people and the future of all life on earth.

### S.16.5 Quercus faginea Lam. s.l. in North Africa, an ongoing taxonomic challenge

Aissi Abdeldjali¹

1 LAPAPEZA, Department of Agricultural Sciences, IS-VSA, University of Batna 1, Algeria

The genus Quercus is known for its taxonomic complexity and it has long been associated with great controversy. The number of taxa is still debated among botanists despite systematists' attempts to clarify and simplify it. The Quercus faginea s.l. complex represents one of the most conclusive and complex examples found in the North-Western Mediterranean and North Africa. Nevertheless, the

systematics of this complex have undergone a remarkable evolution from the first Lamarckian taxa Q. lusitanica and Q. faginea to the present day, especially in the Iberian Peninsula, Tunisia, and Algeria, by virtue of the recognized taxa. Thus, to reevaluate and update the nomenclatural and taxonomic status of Q. faginea complex, 23 morphological traits, and 13 Algerian stands were analyzed, as well as the available Moroccan morphological data and corresponding bibliography, to objectively analyze and compare Moroccan taxa with those found in other regions. Three taxa were identified in Algeria; Q. canariensis, Q. faginea subsp. faginea and Q. faginea subsp. broteroi (Cout.) A.Camus. Although the taxonomic situation in Morocco remains unresolved, the analysis noted the possible presence of the faginea variety in Morocco- despite the tendency towards the taxon in terms of leaf size -, while also anticipating the confirmation of a new morphological analysis that accounts for the stable criteria -i.e., toothed margin- used for an infraspecific distinction. The rest of Morocco's stands seem to be represented by Q. canariensis and Q. faginea subsp. broteroi. Considering the uncertain existence of maroccana, further study of its distinct morphological and biogeographical peculiarity is required.

### S.16.6 Matching herbarium specimens with Mary Vaux Walcott watercolor paintings using machine learning and detective work

Mike Trizna¹, Will Weaver²

1 Data Science Lab, Office of the Chief Information Officer, Smithsonian Institution, Washington, DC, USA. 2 Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, USA

Mary Vaux Walcott's five-volume collection of illustrations and descriptions, "North American wildflowers", was published between the years 1925 and 1929. All of the volumes, which include over 400 watercolor prints, have been fully digitized and made available through the Biodiversity Heritage Library (https://doi.org/10.5962/bhl.title.67774). Many of the illustrations were based on plant specimens collected by Walcott herself or other botanists from the Smithsonian Institution, and specimen labels on their preserved herbaria sheets include written notes that reference this connection. One example is US:1087120 (http://n2t.net/ark:/65665/3fd0d532a-
72a3-4818-9dbe-904d72272759), which has a nota-
tion that it was "Painted by Mrs. Walcott", and closely
matches Plate 44 of Volume 1 (https://www.biodi-
versitylibrary.org/page/42602857). In this project, we
used digitized specimen data to explore candidate
matching specimens, machine learning OCR and
LLM validation tools from the VoucherVision project
(https://github.com/Gene-Weaver/VoucherVision)
to transcribe and clean specimen labels, and com-

puter vision tools from LeafMachine2 (https://github.com/Gene-Weaver/LeafMachine2) to isolate mor-phological and phenotypic traits for comparison. With confident pairs of illustrations and specimens, we investigate the possibility of using the Biodiversity Heritage Library's extensive collection of botanical il-lustrations to extract valuable phenotypic and mor-phological data.

S.17 ACROSS LAND AND WATER:
UNDERSTANDING PLANT GENE FLOW AT A
LANDSCAPE SCALE. SESSION 1

S.17.1 Landscape effects on the spatial distribution of genetic lineages in a widespread, generalist herb

Mareike Daubert¹, Alina Persson¹, Dirk C. Albach¹

1 Institute of Biology and Environmental Sciences, Carl-von-Ossietzky University, Oldenburg, Germany

The majority of landscape genetic studies to this
day has focused on animals, often mammals of
high conservation interest. The studies conducted in
plants have found a significant to no effect of land-
scape features on the genetic structuring of the re-
spective species. Previously, no differentiation was
found between populations of the generalist, wide-
spread herb Veronica chamaedrys (Plantaginace-
e) growing in grasslands under different manage-
ment regimes. We suspect however that grassland
management changes on too short timescales to
affect the species and that factors inhibiting or fa-
cilitating gene flow may reveal themselves at larger
geographic scales. We sampled populations along
a 500 km transect from the German North Sea
coast to the central German xeric zone at the lee
of the Harz mountains. At each location we char-
acterized the surrounding vegetation via Ellenberg
values. Moisture and soil reaction numbers showed
the strongest geographic trends with the steepest
change occurring at the southern margin of the
Harz mountains. We expect these marked changes
to be recognizable in genotyping-by-sequencing
data. The species turned out to be much rarer in the

north German plain than anticipated. This could be
either due to a historical lack of suitable habitat as
the region used to be characterized by extensive
wetlands or due to a recent extinction of popula-
tions as a result of agricultural intensification. Yet,
semi-natural and natural habitats were sampled
preferentially. Should populations north of the cen-
tral uplands prove not to show signs of isolation, it
could indicate a buffering function of gardens and
public green spaces as V. chamaedrys can be fre-
quently found in parks and mature lawns.

S.17.2 Systematics and long-distance dispersal of family Urticaceae

Zeng-Yuan Wu¹

1 Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, China

Urticaceae consists of approximately 54 genera
with more than 2000 species and is widely distrib-
uted in tropical regions but less common in tem-
perate regions, with by far the largest concentration
of genera and species in tropical Asia. This family
has important economic and medicinal value, a
full understanding of relationships within this fam-
ily would help to understand how these ecological
assemblages evolved, and also to detect potential
new sources of medicinal compounds. However, the
infra-familial classification of Urticaceae has been
controversial for more than one century, and rela-
tionships within it remain poorly known. In this talk,
<figure><img src="image_57.png" /></figure>

I introduce some of my studies on the systematics of Urticaceae in the last 10 years based on different molecular markers and research methods. In addition, I present an in-depth study of the biogeography of Urticaceae Integrated multiple lines of evidence including phylogenetic, molecular-dating, biogeographical, ecological, seed biology and oceanographic data, we found that Urticaceae originated in Eurasia ~69 Ma, followed by ≥92 LDD events between landmasses. Under experimental conditions, it was demonstrated that seeds of many Urticaceae floated for >220 days, and remained viable after ten months in seawater, long enough for most detected LDD events, according to oceanographic current modeling. Ecological trait analyses indicated that preferences for disturbed habitats might facilitate LDD. Nearly half of all LDD events involved dioecious taxa, so population establishment in dioecious Urticaceae requires multiple seeds, or for occasional selfing to be possible. This work clearly shows that seawater LDD played an important role in shaping the geographic distributions of Urticaceae, providing empirical evidence for Darwin's transoceanic dispersal hypothesis.

## S.17.3 Tropical Montane Cloud Forest at risk: the importance of unprotected forest areas for tree genetic diversity and connectivity

Yessica Rico¹, Marisol Zurita Solis¹, M. Ángel León-Tapia², Ara N. Miguel Peñaloza¹

1 Red de Diversidad Biológica del Occidente Mexicano, Instituto de Ecología A.C. Michoacán, Mexico.
2 Departamento de Zoología, Instituto de Biología, Universidad Nacional Autónoma de México, Ciudad de México, Mexico

Magnolias are representative tree species of the Tropical Montane Cloud Forest (TMCF) in Mexico, which is one of the most endangered ecosystems due to anthropogenic habitat degradation and climate change. Magnolia schiedeana is a vulnerable and restricted endemic TMCF species, occurring in forest fragments in the Sierra Madre Oriental. We sampled remnant populations across the species range to investigate spatial patterns of genetic diversity and gene flow by genotyping polymorphic microsatellite loci. Our data showed a strong spatial structure, which matches the patchy geographic distribution of M. schiedeana. Contemporary mi-

gration rates between these genetic clusters are very low. Levels of genetic diversity were low in small populations relative to large populations, and no evidence of inbreeding was found. Landscape genetic analysis revealed that geographic isolation was the main factor shaping genetic differentiation, not slope or environmental variation. Urgent conservation actions are needed as most of the cloud forests in which large and genetically diverse M. schiedeana populations persist are not under federal protection, and which currently experience selective logging. Restoring landscape connectivity should be a priority to reduce risks of inbreeding and genetic drift as populations become smaller and geographically isolated.

## S.17.4 Genetic diversity of grassland plants at adaptive and neutral loci – two actors on the stage of landscape change

Iris Reinula¹, Sabrina Träger²,³, Tsipe Aavik¹

1 Institute of Ecology and Earth Sciences, University of Tartu, Estonia. 2 Institute of Biology/Geobotany and Botanical Garden, Martin-Luther-University Halle-Wittenberg, Germany. 3 German Centre for Integrative Biodiversity Research, Germany

Over the past century, changes in land use have significantly reduced the extent of semi-natural grasslands, threatening the functional connectivity, i.e., exchange of genes through pollen and seed dispersal, among populations of plants characteristic of these valuable habitats. Although growing evidence suggests that landscape features can influence gene flow among isolated plant populations, the role of historical land use legacies in shaping the relationship between current landscape characteristics and gene flow in perennial grassland plants remains unclear. Notably, studies often focus solely on genetic diversity at neutral loci (not under natural selection), overlooking genetic diversity at adaptive loci (under natural selection) crucial for plant adaptability to changing conditions. We studied the impact of landscape characteristics on the functional connectivity of 32 populations of the grassland plant Primula veris in two historically semi-natural grassland-dominated landscapes in Western Estonia. Nowadays, one landscape remains grassland-dominated, while forests and agricultural fields prevail in the other. We examined genetic diversity at both neutral and adaptive loci and structure of these populations.
<figure><img src="image_58.png" /></figure>

We also assessed the role of landscape characteristics on gene flow at neutral loci. The relative permeability of different landscape elements for gene exchange depended on landscape context, likely reflecting opposite land use trajectories in these landscapes. Furthermore, the outcome was also affected by different gene flow indices, indicating their context-dependency. Notably, genetic diversity at neutral and adaptive loci showed different results to landscape context. Conclusively, applying connectivity measures based on findings from a landscape setting reflecting only one type of land use trajectory should be avoided. Interpretation of gene flow measures for long-lived plant species should also be approached with caution due to potential delays in their response to landscape changes. Lastly, the correlation between genetic diversity at neutral and adaptive loci is not consistent, warning against using one to estimate the other.

## S.17.5 Applying genomics and metabolomics to elucidate evolution in the homoploid complex of Baccharis L. in Chile

Fabian Schneider¹, Olga Zafra Delgado², Tobias G. Köllner², Frank H. Hellwig¹

1 Friedrich-Schiller-University, Jena, Germany. 2 Max Planck Institute for Chemical Ecology, Jena, Germany

The genus *Baccharis* L. (Asteraceae-Astereae) in Chile is supposed to form a homoploid complex containing about 21 taxa and 33 described hybrids based on morphological and ecological evidence. In this study, we investigated evolutionary processes within this complex using genomic and metabolomic approaches with *Baccharis linearis* (Ruiz et Pavón) Pers., *B. macraei* Hook. et Arn., *B. vernalis* F.H. Hellwig and their putative hybrid *B. x intermedia* DC. in Central Chile. The sampling covered selected populations ranging from La Serena in the north to Concepción in the south. Next generation sequencing (ddRad/Illumina) and untargeted metabolomics (LC-qTOF) was performed using silicagel-dried material. The initial hypothesis on the hybrid nature of *B. intermedia* was corroborated by genomic and chemical evidence. Within the morphologically intermediate hybrid, a combination of genetic markers from both parents could be detected. The hybrid shows a significantly higher heterozygosity than both parental taxa. Moreover, metabolomics analyses revealed that *B. in-

termedia* has a mixed chemotype and combines the chemistry of the parental species. Both parents exhibit a north-south genetic differentiation that goes in parallel with their chemistry. This pattern is also found in the hybrid pointing to its polytopic origin. There is evidence for gene flow between the hybrid and the parental species, albeit at a low level, allowing independent evolution of the hybrid taxon. Time and history of the taxa involved are discussed in the light of ecology vegetation history.

## S.17.6 Employing landscape genetics to forecast climate-driven habitat changes for high-mountain plant endemics in the Canary Islands

Sonia Sarmiento Cabello¹, Priscila Rodríguez Rodríguez¹, Yessica Rico², Leticia Curbelo Muñoz¹, Pedro A. Sosa Henríquez¹

1 Instituto Universitario de Estudios Ambientales y Recursos Naturales, Las Palmas de Gran Canaria University, Las Palmas de Gran Canaria, Spain. 2 Instituto de Ecología, A.C., Red de Diversidad Biológica del Occidente Mexicano, Centro Regional del Bajío, Pátzcuaro, Michoacán, Mexico.

Climate change poses a significant threat to endemic and native flora, particularly those inhabiting upper vegetation zones. While the impact of climate change on continental alpine ecosystems has been extensively studied, little progress has been made in understanding high mountain ocean ecosystems. Using a combination of species distribution models and landscape genetic methods, our study focuses on species inhabiting high mountain ecosystems in the Canary Islands. In this context, we aim to 1) characterize genetically different populations, 2) estimate interpopulation gene flow and functional connectivity, 3) determine the current and forecasting future habitat suitability, and, finally, 4) assess the impact of climate change on these plant species. Like alpine regions, we expect that species within the upper vegetation zones of the Canary Islands are vulnerable to population declines due to climate change, especially those with restricted distribution and short-distance dispersal, such as the Teide violet. Ultimately, our research aims to develop enhanced conservation strategies for the endemic and native flora of the Canary Islands.
# S.18 INVENTORYING THE PLANT DIVERSITY OF THE EURO-MEDITERRANEAN AREA: INTEGRATING TAXONOMIC PROGRESS INTO DYNAMIC WEB CHECKLISTS AND ELECTRONIC FLORAS

## S.18.1 How to classify apomictic polyploid complexes - challenges and perspectives

Elvira Hörandl¹

1 Department of Systematics, Biodiversity and Evolution of Plants (with herbarium), University of Goettingen

Apomixis, the reproduction via asexually formed seeds, avoids cycles of meiosis and fertilization. Apomictic lineages appear scattered in the phylogenies of plants, and often comprise widespread and abundant taxa, which makes them highly relevant for biodiversity research. Apomixis poses a problem for species concepts and delimitation, because the popular biological species concept is per definition not applicable. Alternative species concepts, like the phylogenetic species concepts, cluster species concepts, evolutionary and ecological species concepts are theoretically applicable, but pose in theory and practice still many problems. A major conceptual problem is the predominant hybrid origin of many apomictic plants, which violates assumptions of tree-like diversification patterns, but also blur boundaries between clusters and lineages in the other classical concepts. Genetic clustering and vertical lineage formation remain weak without the homogenizing effects of sexuality. Pluralistic approaches for species delimitation are nowadays preferred for taxonomic decisions, i.e., case-by-case applications of concepts based on combinations and multiple datasets. Apomictic lineages might be included under one species name, as it often applied to autopolyploids. In allopolyploid complexes the sexual progenitors can be normally classified on species level, but the vast majority of ill-defined asexual lineages could be lumped under a cluster concept or named just as nothotaxa. The formal designation of hybrids is possible according to the Code if at least one parental taxon is known, which applies to most young apomictic complexes. This

strategy would avoid swamping databases, floras and checklists with hundreds of species names for ill-defined taxa. Only few obligate long-term apomictic lineages exist in plants, without knowledge of progenitors. Such cases may deserve a classification as species (agamospecies). Application of genomic data and artificial intelligence tools will improve the classification process and help to delimit taxa as comparative units that can be handled in databases, floras, and checklists.

## S.18.2 Assessing local and national floristic diversity through the Portal to the Flora of Italy

Lorenzo Peruzzi¹, Fabrizio Bartolucci², Gabriele Galasso³, Gianni Bedini¹, Stefano Martellos⁴, Giannantonio Domina⁵, Fabio Conti²

1 University of Pisa, Italy. 2 University of Camerino, Italy. 3 Natural History Museum of Milano, Italy. 4 University of Trieste, Italy. 5 University of Palermo, Italy.

Approximately two decades ago, the Working Group for Floristics, Systematics and Evolution of the Italian Botanical Society initiated a collaborative project to develop a checklist of the Italian vascular flora. The first project output was a book, published in 2005, followed by a significant update in 2018. Another update is scheduled for release in early 2024. The project triggered two crucial requirements: the digital storage and publication of floristic records, and the dissemination of the checklist through an online information system. Consequently, the collaborative floristic project "Wikiplantbase" (http://bot.biologia.unipi.it/wpb/italia) was launched in 2013, and in 2018 the online "Portal to the flora of Italy" (https://dryades.units.it/floritaly/index.php) was introduced to the scientific community. These two online tools operate in tandem, ensuring continuous updates and interoperability. They thus
constitute a unified system, serving as a robust and reliable reference for the nomenclature, taxonomy, and distribution of the Italian vascular flora. Additional resources are slated to be incorporated into the system. These include a database storing protologues, type localities and other pertinent information about type designations for accepted plant names described in Italy, and the "Chrobase. it" database (http://bot.biologia.unipi.it/chrobase/index.php), focusing on chromosome numbers. Furthermore, the "The Italian flora of human interest" database (https://www.optima-bot.org/index.php/en/projects/8-category-en-gb/217-the-italian-cwr-whp-database) will contribute to the expanding repository. An ongoing effort involves establishing interoperability between this system and external initiatives, such as the "World Flora Online" (https://www.worldfloraonline.org/), "Plant of the World Online" (https://powo.science.kew.org/), and the "Euro+Med Plantbase" (https://europlusmed.org/). This integrated approach aims to create a more comprehensive and interconnected resource for sharing and accessing a wide spectrum of botanical data.

### S.18.3 Designing a comprehensive online and print flora from scratch – the Flora of Greece project

Panayotis Dimopoulos¹

1 Laboratory of Botany, Department of Biology, University of Patras, Greece

By starting from scratch, the Flora of Greece project represents a significant initiative aimed at constructing a thorough and annotated catalogue of the country's rich plant diversity, with both online and print components. Launched in 2010 and concluding three years later, in 2013, the "Vascular plants of Greece: An annotated checklist" (VPG) is the first comprehensive inventory of the flora of Greece more than a century after Eugen von Halácsy, finalized the most recent complete Flora of the country in its political borders. Since 2017, the project utilizes an advanced web tool (EDIT Platform for Cybertaxonomy) to facilitate easy access and navigation through extensive collection of taxonomic information. Users can access the electronic version of the VPG through the Flora of Greece website (https://portal.cybertaxonomy.org/flora-greece). The web checklist evolves dynamically,

undergoing systematic and regular revisions to incorporate emerging scientific knowledge. The 1st version of the "Flora of Greece web" was published in May 2017 and the current, 5th version, summarizes all published information to the end of November 2023. This ambitious project stands as a collaborative achievement, based on the expertise of numerous scientists, aiming to the construction of a comprehensive database, currently comprising 5960 species and 2015 subspecies (6850 taxa). Looking ahead to 2024, the Flora of Greece project is poised to release an updated version. The project adheres to the nomenclatural adaptation via the APG IV, ensuring consistency with contemporary botanical standards. This new iteration, to be published in both online and print formats, will feature expanded content including additional descriptions and distribution maps. This ongoing commitment to floristic exploration and documentation underscores the project's enduring impact on the understanding and conservation of Greece's rich plant diversity.

### S.18.4 Euro+Med PlantBase – how to integrate taxonomic knowledge and provide plant diversity data at a continental level

Eckhard von Raab-Straube¹

1 Freie Universität Berlin, Botanic Garden and Botanical Museum, Berlin, Germany

Euro+Med PlantBase (E+M), a long-term project founded in the year 2000, has developed into a well-known standard resource for information on systematics, nomenclature and distribution of vascular plants and bryophytes in Europe and the Mediterranean region. At present, E+M contains more than 45,000 taxa, over 150,000 scientific names, nearly 150,000 common names in more than 40 languages, and ca. 380,000 source-referenced distribution records. The data are open access and can be retrieved through the Euro+Med Data Portal (https://europlusmed.org/), online in its present form since 2020. E+M provides a permanently updated taxonomic backbone and a dynamic checklist for native and alien plants in Europe, the Caucasus, the circum-Mediterranean countries and the Macaronian archipelagos. Distribution is given for areas which correspond to all countries and most larger
<figure><img src="image_59.png" /></figure>

islands of the region. E+M is currently maintained
by an informal consortium of participating Europe-
an institutions, with the secretariat at the Botanic
Garden Berlin since 2004. The editorial team of E+M
continuously updates the systematic treatments
of the checklist and adds new or corrects existing
records. Initially based on *Flora Europaea* and inte-
grating information from all taxonomic and floristic
literature sources from the area, E+M is the most
comprehensive resource on accumulated historical
and actual floristic data at country level of the Eu-
ro-Mediterranean region. It keeps track of the new-
est publications in plant systematics and evolution,
nomenclature and floristics, thus ensuring that the
database is up to date in every respect. At present,
approximately 200 taxa a year are added which are
described as new to science from the E+M area. E+M
also contributes taxonomic and distribution data to
the World Flora Online (WFO) and links to other ma-
jor online resources, thereby serving as a gateway to
European and Mediterranean flora portals.
Symposia Session 2

**S.19 BIOGEOGRAPHY AND DIVERSIFICATION**
**OF INTERCONTINENTAL TROPICAL PLANT**
**DIVERSITY. SESSION 2**

**S.19.1 Origin and**
**biogeographical history of**
**the Piper (Piperaceae)**

Dominik Metschina¹, Rosabelle Samuel¹, Luiz Augusto Caus dos Santos¹, Maarten Christenhusz², James W. Byng³, Deepthi Yakandawala⁵, Tara de Silva⁶, Anushka Wickramasuriya⁶, Mark W. Chase¹,²,⁴

1 Department of Botany and Biodiversity Research, University of Vienna, Vienna, Austria. 2 Department of Environment and Agriculture, Curtin University, Perth, Western Australia, Australia. 3 Hortus Botanicus, Technical University Delft, The Netherlands. 4 Royal Botanic Gardens, Kew, Richmond, Surrey, UK. 5 Faculty of Science, University of Peradeniya, Sri Lanka. 6 Department of Plant Sciences, University of Colombo, Sri Lanka

Target enrichment for Piperaceae, including all five genera, produced a well-supported maximum likelihood tree in which there was a good support for (Verhuellia ((Manekia + Zippelia) + (Piper + Peperomia))). Originating in South America in the Late Cretaceous, Piper then dispersed during the middle Eocene climatic optimum (ca. 40 Mya, when tropical species reached higher latitudes) to southern Africa and the Pacific islands first, followed by New Guinea, Southeast Asia and the Philippines. During the Oligocene the genus radiated in Southeast Asia and reached East Asia, India, Sri Lanka and Australia and re-colonised Africa. The New Caledonian and Vanuatuian species are sister to the New Guinean and Philippine taxa rather than the Pacific species. Once Piper left South America it exhibited a great number of intercontinental dispersals throughout its subsequent evolutionary history.

**S.19.2 Biogeography of**
**Indian Persea group**
**(Lauraceae) - filling**
**the gaps in the global**
**phylogeny**

Nabasmita Malakar¹,², Gudasalamani Ravikanth¹, K. Praveen Karanth³, Ganesan Rengaian¹

1 Ashoka Trust for Research in Ecology and the Environment, Bangalore, India. 2 Manipal Academy of Higher Education, Manipal, Karnataka, India. 3 Centre for Ecological Sciences, Indian Institute of Science, Bangalore, India

We investigated the phylogeny and biogeography of the basal angiosperm group Persea (Lauraceae) that comprises eight accepted genera i.e., 1) *Alseodaphne* 2) *Alseodaphnopsis* 3) *Apollonias* 4) *Dehaasia* 5) *Machilus* 6) *Nothaphoebe* 7) *Persea* and 8) *Phoebe*. In India, Persea group is distributed in low-elevation evergreen forests to broad leaved temperate forests of Himalayas and mid-elevation evergreen forests of Western Ghats, south India. We aim to understand the biogeographic origins of the *Persea* group and to decipher the times and modes of evolution in the Indian subcontinent compared to the Asian region. Two nuclear and one chloroplast gene marker are sequenced for ca. 100 samples collected across Northeast region and Western Ghats of India. We mapped the sequences of Indian *Persea* group in global dataset. Phylogenetic relationships were reconstructed using maximum likelihood and Bayesian inference methods. Divergence time estimated using BEAST 2.4.8. and Ancestral geographical ranges performed using BIOGEOBEARS. The *Persea* group has diverged around ~55.3 Mya (95% highest posterior density (HPD): 41.4 – 69.9 Mya) in China. We expect the probable divergence time of *Persea* group in India is early-mid Eocene. Also,
<figure><img src="image_60.png" /></figure>

molecular study shows the *Apollonias arnottii*, sin-
gle known species of the genus globally, has to be
shifted to the genus *Phoebe*. Phylogenetic tree we
developed also supports the *Persea* group is not
monophyletic. The *Persea* group requires in-depth
taxonomic study of flower and fruit collections to re-
solve all the clades of different genera globally. This
is the first attempt to understand the phylogenetic
relationship and historical biogeography Indian Per-
sea group in the global phylogeny.

S.19.3 Time calibrated
phylogeny of Cunoniaceae
reveals the biogeographical
history of the Andean genus
Weinmannia

Francisco Fajardo-Gutiérrez¹,²,⁸, Christine Edwards³, J. Sebastián Tello³, Alfredo Fuentes³,⁴, Nora H. Oleas⁵, Ricardo A. Segovia⁶, Mariasole Calbi⁷, Markus Dillenberger¹,⁸, James E. Richardson⁹, Yohan Pillon¹⁰, Thomas Borsch¹,⁸

1 Botanischer Garten und Botanisches Museum Berlin-Dahlem. Berlin, Germany. 2 Jardín Botánico de Bogotá José Celestino Mutis, Bogotá, Colombia. 3 Missouri Botanical Garden, St. Louis, USA. 4 Universidad Mayor de San Andrés, La Paz, Bolivia. 5 Universidad Tecnológica Indoamérica, Ambato, Ecuador. 6 Universidad de Concepción, Concepción, Chile. 7 University of Genoa, Genoa, Italy. 8 Freie Universität Berlin, Berlin, Germany. 9 University College Cork, Cork, Ireland. 10 Université Montpellier, Montpellier, France

Cunoniaceae, mostly distributed in the Southern
hemisphere, comprises 27 genera and c. 335 spe-
cies. The highest diversity can be found in New
Caledonia and South America. Also, diversity is con-
centrated in the genus *Weinmannia* (c. 80 species),
which is dominant in cloud and montane forests
along the Andes. Other ten to fifteen *Weinmannia*
species are scattered throughout the Americas in
the Atlantic Forest (South Brazil), the Guyana shield,
Central America, Mexico, and the Caribbean islands.
Our main objective is to reveal the phylogeograph-
ic history and diversification patterns of the group.
We used a relaxed molecular clock, based on DNA
sequences of three plastid markers *trnK-matK*,
*trnL-trnF*, and *rps3-rpl16*, and twelve fossil calibra-
tions, with an extended sampling across the Rosid
lineages. We found the Cunonieae tribe (*Cunonia*,

*Pancheria, Pterophylla and Weinmannia*) diverging
during the late Eocene (~39.6 Ma), and the estimat-
ed age of *Weinmannia* (~34 Ma), correspond with
the age of the Eocene-Oligocene Transition (33.9
Ma). This transition was characterized by the first
formation of the Antarctic ice sheet and the isolation
of the Gondwanan groups caused by the opening
of the Drake Passage between South America and
Antarctica, and the Tasman Seaway between Aus-
tralia and Antarctica. Such continental rearrange-
ment explains the current distribution of the taxa
in the tribe. The most basal species of *Weinmannia*
are in the Mascarenes Islands and Chile, while the
central and northern Andean species show a recent
evolutionary radiation estimated to have occurred
~5.5 Ma, which is consistent with the two major puls-
es of Andean uplift during the Miocene and Pliocene
at c.12–6 Ma and ca. 4.5 Mya. Our results support
the idea that continental drift and orogeny played
a crucial role in determining the distribution and di-
versification of *Weinmannia*.

S.19.4 Unlocking
Parablechnum from the
field to the lab: a Hyb-
Seq approach to unravel
the global disjunction of a
young fern genus

Sonia Molino¹,², Guillermo Santos Rivilla¹,
Mario Mairal¹, Weston Testo³, Peter
DeLange⁴, Rosenber Hurtado⁵, James
Rodger⁶, Rafael Medina Bujalance¹

1 Universidad Complutense de Madrid. Madrid, Spain. 2 Universidad Europea de Madrid, Madrid, Spain. 3 Pringle Herbarium, University of Vermont, Burlington, USA. 4 Unitec Institute of Technology, Auckland, New Zealand. 5 Herbario Nacional de Botivia, La Paz, Bolivia. 6 Stellenbosch University, Stellenbosch, South Africa

Parablechnum is the most speciose genus of the fern family Blechnaceae, particularly represented in vulnerable habitats such as tropical montane cloud forests. Its 68 species exhibit a Gondwanan distribution, predominantly spread across two major centers of diversity—one in the Neotropics and the other in Australasia—; additionally, there are only three African species found in Southern Africa, Madagascar, and the Mascarene archipelago. Reconstructing the evolutionary history of these ferns has been
<figure><img src="image_61.png" /></figure>

hampered by their singular circumstances. Recent studies show that the genus is undergoing a rapid diversification that obscures its backbone phylogeny and hence the explanation of its current disjunct distribution. The taxonomy of the genus is still poorly understood as several species groups need further attention to be adequately circumscribed. Additionally, phenomena such as hybridization and cryptic speciation seem frequent in the genus, making it difficult to complete the phylogenetic approach. Combining the specimens from two recent field campaigns with herbarium material, we are attempting to improve the quality and quantity of molecular data. Our approach aims to reach a more detailed phylogenetic resolution via Hyb-Seq using the GoFlag probe set. Our preliminary results show a complex evolutionary history of a dynamic group shaped by long-distance dispersal events and ongoing diversifications. Guided by these results we are undertaking a comprehensive taxonomic re-evaluation of the whole genus with the perspective of completing a global monograph.

**S.19.5 Exploring evolutionary transitions across biomes in Zornia J.F.Gmel. (Leguminosae: Papilionoideae)**

Laís C. Zeferino¹,²,³, Flavia F. Pezzini², Kyle G. Dexter³, Gwilym P. Lewis⁴, Ana Paula Fortuna Pérez¹

1 Universidade Estadual Paulista "Julio de Mesquita Filho", São Paulo, Brazil. 2 Royal Botanic Garden Edinburgh, Edinburgh, UK. 3 University of Edinburgh, Edinburgh, UK. 4 Royal Botanic Gardens, Kew, UK.

The genus Zornia J.F.Gmel is the second most speciose representative of the Adesmia clade (Leguminosae: Papilionoideae), with ca. 80 species. Zornia is the only genus within the clade with a global distribution, mainly occurring in tropical and subtropical regions of the world. A previous phylogeny for Zornia revealed that most species diverged in Brazil ca. 8–10 mya, and suggested a single transoceanic dispersal event from the Americas to the Old World ca. 5 mya. Here, we augment the previous phylogeny with new sampling from Central America, Asia, Africa and Oceania. We aimed to investigate evolutionary patterns of distribution in Zornia and answer biogeographic questions related to ancestral range

estimation and evolutionary transitions between biomes. Our results suggest that Zornia originated in the dry forest in Northeast Brazil. From there, the evolutionary path of the genus continued to the savannas of the Americas, where 40% of the present species occur. Lineages then adapted to the high elevation grassland in South America and Central America. The genus dispersed to the high elevation grassland in Africa and then to the savannas in India and Australia. Our study shows the trans-oceanic dispersal occurred in Zornia, as previously it was not clear if this dispersal occurred from America to Africa or Australia first. We also clarify how the evolutionary transitions between biomes occurred in the genus, which is important to understand the dynamics of adaptation particularly to dry environments where Zornia mostly occurs.

**S.19.6 Historical biogeography and niche evolution of Lecythidaceae in the American tropics**

Diana Medellín-Zabala¹, Oscar M. Vargas², Deise Pereira Gonçalves¹, Raquel C. Pizzardo¹, Andre Chanderbali³, Douglas Soltis³, Pam Soltis³, Stephen Smith¹ & Christopher Dick¹

1 Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, USA. 2 Department of Biological Sciences, University of California, Santa Cruz, USA. 3 Florida Museum of Natural History, University of Florida, Gainesville, USA

Lecythidaceae (Ericales) is a pantropical family of woody plants of ca. 278 tree species with three subfamilies: *Foetidioideae* (Madagascar), *Planchnioideae* (Asia and Africa), and *Lecythidoideae* (ca. 232 species) restricted to the Neotropics. This family is within the 20 most-species rich families of trees in the lowland Amazon forests, providing important ecological services such as carbon sequestration and food resources for pollinators and seed dispersers. The global center of species richness and ecological importance is in the Amazon basin and Guiana Shield, where most Lecythidaceae research has been focused. However, there are genera occurring in the Andean and Chocó Biogeographic regions where several knowledge gaps lie. Despite multiple studies having been performed for Lecythidaceae, there are still incongruences among hypotheses about the
evolution of this family. To infer the geograph-
ic history of Lecythidaceae in the Neotropics,
and identify areas of importance for its diver-
sification, we performed a Maximum Likelihood
analysis in IQ-TREE, based on nuclear markers
targeted by the Angio353 probes in 94 species,
and an ancestral range reconstruction, using a
dispersal-extinction-cladogenesis model (DEC)
in BioGeoBEARS. According to our results, there is
a high uncertainty about the ancestral area for
the Neotropical clade. However, the Southeastern
Amazonia was reconstructed as the most prob-
able ancestral area for the zygomorphic-flow-

ering clade, originated in the Paleogene (~34
Mya), while Central America and the Chocó were
recovered as the most plausible ancestral area
for the actinomorphic-flowering clade (originat-
ed ~37 Mya). Since most of the species included
in this reconstruction occur in the Amazon basin
and given the complexity of wetland habitats and
their association with the Andean uplift that most
likely had an important role in the evolution of
Amazonian Lecythidaceae, increasing sampling
from the InterAndean Valleys and Chocó will al-
low us to better understand the niche evolution
and diversification history of this family.

S.20 CONTRASTING DIVERSITY PATTERNS,
BIOGEOGRAPHY, AND CONSERVATION ISSUES
IN NORTHERN AND SOUTHERN HEATHERS
(ERICEAE, ERICACEAE)

S.20.1 Heath species
help reconstruct the
biogeographic role of the
Strait of Gibraltar

Antonia Salces-Castellano¹,², Pablo Vargas³, Fernando Ojeda⁴

1 Department of Biology, Ecology and Evolution, Université de Liège, Belgium. 2 Unit of Evolutionary Biology & Ecology. Université Libre de Bruxelles, Belgium. 3 Departamento de Biodiversidad y Conservación, RJB-CSIC, Madrid, Spain. 4 Departamento de Biología-IVAGRO, Universidad de Cádiz, Cádiz, Spain

The Strait of Gibraltar is characterised by the di-
versity and uniqueness of its terrestrial flora. The
floristic similarity between both sides of the Strait,
together with the existence of some discontinu-
ities, illustrates its biogeographical importance as
a dispersal bridge/barrier. On the other hand, the
Strait of Gibraltar has acted as a biogeographi-
cal refuge for flora from the Pleistocene glacia-
tions. Many plant species found on both sides of
the Strait are associated with sandy, very acidic
and infertile soils. These include the heather Cal-
luna vulgaris and Erica australis, characteristic
species of the Mediterranean heathland or herri-
za. The Strait was an important glacial refuge for

these species, followed by a post-glacial expan-
sion along the western Iberian Peninsula. Howev-
er, the Guadalquivir valley, dominated by clayey,
non-acidic, fertile soils, would represent an edaph-
ic barrier to the northward expansion of these ac-
idophilic species. How did they overcome it? The
phylogeographic analyses of these two heathland
species were reviewed, and the geological and
geomorphological literature of the Strait of Gibral-
tar region was examined. For both species, a cer-
tain genetic discontinuity is observed between the
European area of the Strait and those of the rest of
the Iberian Peninsula. In contrast, there is a striking
genetic link between the W Iberian Peninsula and
the African part of the Strait. Assuming a sea-level
drop of about 140 m, the topography of the Strait
of Gibraltar and the continental shelf of the Gulf of
Cadiz, as well as the tectonic nature of their sub-
strates, we suggest the existence of a glacial cor-
ridor between the African side of the Strait and the
Portuguese Algarve. Confirmation of this Tingita-
no-Algarvian corridor using NGS approaches will
help to clarify the role of the Strait of Gibraltar as
a bridge or dispersal barrier in the geographical
distribution of plants.
## S.20.2 Phylogenetics, biogeography and phenotypic variation of four species of heathers (Erica L., Ericaceae) with contrasting distributions

Jaime Fagúndez¹,², Iván Rodríguez-Buján², Pilar Díaz-Tapia¹,³

1 Universidade da Coruña, BIOCOST research group, Centro Interdisciplinar de Química e Bioloxía (CICA), A Coruña, Spain. 2 Universidade da Coruña, Departamento de Bioloxía, Facultade de Ciencias, A Coruña, Spain. 3 Universidade de Santiago de Compostela, Departamento de Botánica, Santiago de Compostela, Spain

Erica tetralix, E. ciliaris, E. mackayana and E. andevalensis form a robust clade within the heathers (Erica L.) of the northern hemisphere. They share a number of traits such as their low size, the pluri-cellular glandular trichomes, and their ecological niche of permanently wet conditions. However, they cover different geographic areas, ranging from the widespread North Atlantic E. tetralix, to the narrowly endemic E. andevalensis of South western Iberia. Moreover, hybridisation occurs in northern areas between E. tetralix and E. ciliaris or E. mackayana, but not in overlapping southern populations. Here we present a dataset of over 400 plants obtained from the distribution range of the four species. Most samples have been analysed by means of genetic analyses using SNPs (nextRAD sequencing). Furthermore, we conducted measurements on an array of morphological traits, encompassing macro and micromorphological traits, including reproductive and vegetative characters. In this talk, we present the first results on the biogeography, phylogenetic relationships and morphological variation at the species, population and individual level including i) The biogeography of E. mackayana, which shows a clear pattern of recent multiple introduction events for the Irish populations from northern Spain, ii) both genetics and morphology support the species taxonomic level of E. andevalensis, and iii) the hybrids of E. tetralix and E. mackayana or E. ciliaris are intermediate in their morphology and genotype, and are produced only in certain regions. Results from this model group can aid in the interpretation of evolutionary and biogeographic patterns such as the northern recolonization by plants from southern refuges after the ice age.

## S.20.3 Phylogenetic diversity and conservation prioritisation of Erica (Ericaceae)

Michael D. Pirie¹,¹⁴, Dirk U. Bellstedt²,
Roderick W. Bouman³, Jaime Fagúndez⁴,⁵
Berit Gehrke¹, Martha Kandziora⁶, Nicholas
C. Le Maitre⁷, Seth Musker⁸, Ethan
Newman⁹, Nicolai M. Nürk¹⁰, E.G.H. Oliver¹¹,
Sebastian Pipins¹²,¹³, Timotheus van der
Niet⁹, Félix Forest¹²

1 University Museum, University of Bergen, Postboks, Bergen, Norway. 2 Department of Biochemistry, University of Stellenbosch, Private Bag X1, Matieland, South Africa. 3 Hortus botanicus Leiden, Leiden University, RA, Leiden, the Netherlands; Naturalis Biodiversity Center, RA, Leiden, the Netherlands. 4 Universidade da Coruña, BIOCOST research group, Centro Interdisciplinar de Química e Bioloxía (CICA), A Coruña, Spain. 5 Universidade da Coruña, Departamento de Bioloxía, Facultade de Ciencias, A Coruña, Spain. 6 Department of Botany, Faculty of Science, Charles University, Prague, Czech Republic. 7 Department of Genetics, University of Stellenbosch, Private Bag X1, Matieland, South Africa. 8 Department of Biological Sciences, University of Cape Town, Private Bag, Rondebosch, South Africa. 9 School of Life Sciences, University of KwaZulu-Natal, Scottsville, Pietermaritzburg, South Africa. 10 Department of Plant Systematics, Bayreuth Centre of Ecology and Environmental Research, University of Bayreuth, Bayreuth, Germany. 11 Department of Botany and Zoology, University of Stellenbosch, Private Bag X1, Matieland, South Africa. 12 Royal Botanic Gardens, Kew, Richmond, UK. 13 Department of Life Sciences, Imperial College, London, UK; On the Edge, London, UK

Estimates of the numbers of vascular plant species currently under threat of extinction are shockingly high, with the highest extinction rates reported for narrow-range, woody plants, especially in Mediterranean climate and tropical biodiversity hotspots. The genus Erica is a prime example: of the around 850 species, all shrubs or small trees, a large proportion are narrowly endemic to localities within the Cape Floristic Region of South Africa. Just under 200 are known to be threatened and a further 100 are 'Data Deficient'. We need to target conservation work as well as research to fill the most problematic knowledge gaps. This can be especially challenging in large genera such as Erica with numerous threatened species that are more or less closely related. One approach involves combining knowl-
<figure><img src="image_62.png" /></figure>

edge of phylogenetic diversity with that of IUCN threat status to identify the most evolutionarily distinct and globally endangered (EDGE) species. We present an expanded and improved phylogenetic hypothesis for *Erica* (representing 67% of described species diversity) and combine this with available threat and distribution data of species to assess which species and geographic areas should be targeted for conservation effort to maximise preservation of phylogenetic diversity. This analysis delivers priority lists of phylogenetically diverse taxa - threatened, or data deficient - and of areas. Priority lists can be cross-referenced to existing living and seed banked ex situ collections and used to target new and updated threat assessments and conservation action.

## S.20.4 Pollinator shifts and budding speciation in the Cape Floristic Region's heathers

Seth D. Musker¹, Nicolai M. Nürk², G. Anthony Verboom¹, Michael D. Pirie³

1 Department of Biological Sciences, University of Cape Town, Cape Town, South Africa. 2 Department of Plant Systematics, University of Bayreuth, Bayreuth, Germany. 3 University Museum of Bergen, Bergen, Norway

Of the roughly 900 species of *Erica* worldwide, 690 (75%) occur in the Cape Floristic Region. This taxonomic diversity is accompanied by an impressive array of floral phenotypes corresponding to different modes of pollination, including wind, bird, bee, fly, and even rodent pollination. We focused on a clade with evidence of multiple shifts between bee and sunbird pollination syndromes and used genome-wide data to improve on previous estimates of the clade's phylogeny. This provided a much clearer picture of the group's evolutionary history; however, the picture is still by no means clear. What we can say is that the group's diversification happened very rapidly and is certainly still ongoing. Intriguingly, budding speciation – which is when one species gives rise to a new species without itself changing at all – appears to be a common occurrence and is often accompanied by a shift from bird to bee pollination. The prevalent paradigm of speciation by bifurcation might therefore be a poor model of what really happened during the group's spectacular diversification.

## S.20.5 Systematics and evolution of the true blueberries (Vaccinium sect. Cyanococcus, Ericaceae)

Peter W. Fritsch¹, Andrew A. Crowl², Bruce A. Sorrie³, and Paul S. Manos⁴

1 Botanical Research Institute of Texas, Fort Worth Botanic Garden, Fort Worth, Texas, USA. 2 Florida Museum of Natural History, University of Florida, Gainesville, Florida, USA. 3 Coker Herbarium, North Carolina Botanical Garden, University of North Carolina, Chapel Hill, North Carolina, USA. 4 Department of Biology, Duke University, Durham, North Carolina, USA

The true blueberries (Vaccinium sect. Cyanococcus) constitute a clade of about nine to 24 species in temperate North America. This group served as a model system during the Modern Synthesis for examining the origins, prevalence, and diversification of polyploidy in nature, and remains intensively studied because of its economic importance as a food crop. Nonetheless, its taxonomy and evolutionary history is still uncertain, particularly regarding the relative importance of allo- versus autopolyploidy in the evolution of the group, the extent to which levels of ploidy concord with species boundaries, and the utility of the morphological characters traditionally used for delimiting taxa. To address these knowledge gaps, we have collected over 750 silica-gel-dried leaf samples from natural populations with herbarium vouchers and photographs, nearly 500 of which have been analyzed with flow cytometry to estimate ploidy. A robust diploid phylogenetic estimate has been generated for 36 samples of known ploidy with a target-enrichment phylogenomic approach. To this diploid framework we have added polyploids in several ways to test their evolutionary origins. We found a strong correlation of leaf and stem stomata size and density with ploidy across the clade. With the knowledge gained from these studies, we have examined thousands of herbarium specimens from key U.S. herbaria to begin the process of a comprehensive taxonomic revision that will uniquely include expansive species descriptions, specimens cited, and distribution maps. Progress indicates that the revision will vary substantially from prior work, e.g., it includes the taxonomic resolution of two polyploid species to which names have been extensively misapplied, the resurrection of a localized polyploid endemic currently buried in synonymy, and the discovery of two diploids with
<figure><img src="image_63.png" /></figure>

unique morphology and localized geographic distri-
bution that may represent undescribed species. We
also discovered a morphological means to discern
"rabbit-eye" blueberry cultivars that have escaped
from cultivation.

S.20.6 Hybridisation and the
debated species boundaries
in Rhododendron subgenus
Pentanthera

Gulzar Khan¹, Raulf Baur¹, Dirk C. Albach¹

1 Carl von Ossietzky Universität Oldenburg

**Rhododendron** (Ericaceae) is one of the largest gen-
era of woody plants with 1156 species. The genus has
been divided into five subgenera, of which *R*. subg.
*Pentanthera* G. Don comprises a group of highly or-
namental species, with interesting distribution, in-
digenous to North America, Japan, China, and the
Caucasus regions. The species (17 species) assigned
to *R*. section *Pentanthera* are commonly known as
Azaleas. The section has highly debated taxonomy
and unresolved phylogeny. We here used the GBS
techniques to assess the species boundaries using
the population and phylogenomic approaches. Our
initial results suggest that there is frequent admixture
among different species of *R*. section *Penanthera*.
The initial phylogenomic results also support reticu-
lation in the tree backbone of the section.

S.21 NEW FRONTIERS IN PLANT
PHYLOGENOMICS. SESSION 2

S.21.1 Darwin Tree of Life,
towards reference genomes
of an entire flora

Michelle L. Hart¹, Laura L. Forrest¹

1 Royal Botanic Garden Edinburgh, Scotland, UK

The Darwin Tree of Life project has the ambitious
goal of producing reference quality genomes of all
eukaryotic species in Britian and Ireland. Within this
broader goal, the botanical aim is to collect 1900
species of land plant from Britain and Ireland and
produce reference genomes from over half of these
species by the end of 2024. In building such a large
scale reference genome resource, considerable at-
tention has been given to standard operating pro-
cedures and protocols. This involves work undertak-
en by Genome Acquisition Laboratories (GALs) at
the Royal Botanic Garden Edinburgh and the Royal
Botanic Gardens Kew and includes developing tar-
get species lists, defining and adhering to compre-
hensive meta-data standards, collection of plants
directly snap frozen on dry-ice or liquid nitrogen in
the field, and then using DNA barcoding to check
species identify, and undertaking genome size es-
timates with flow-cytometry to guide sequencing
efforts. High quality plant tissues are then submitted
to the Wellcome Sanger institute for DNA extractions
and genome sequencing using a combination of

PacBio Hifi sequencing for the main assembly and
scaffolding with HiC. In this presentation we give an
overview of botanical progress on the Darwin Tree
of Life project, summarising achievements (includ-
ing the successful sequencing of the 90 gb mistle-
toe genome) and also the challenges including the
multitude of difficulties that arise when from work-
ing with diverse tissues sources and often very small
amounts of starting material.

S.21.2 Towards a better
understanding of the
genomics of tropical
forests: a case study from
Singapore

Matti A. Niissalo¹, Sitaram Rajaraman²,³,
Jun Ying Lim²,⁴, Le Min Choo¹, Jia Jun
Ngiam², Kang Min Ngo⁵, Shawn K. Y. Lum⁵,
Victor A. Albert²,⁶, Charlotte Lindqvist²,⁶,
David J. Middleton¹,², Gillian S. Khew¹,²,
Jarkko Salojärvi²,³

1 Singapore Botanic Gardens, National Parks Board, Singapore. 2 School of Biological Sciences, Nanyang Technological University, Singapore. 3 Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental
<figure><img src="image_64.png" /></figure>

Sciences, University of Helsinki, Helsinki, Finland. 4 Department of Biological Sciences, National University of Singapore, Singapore. 5 Asian School of the Environment, Nanyang Technological University, Singapore. 6 Department of Biological Sciences, University at Buffalo, New York, USA

### S.21.3 What can we do with a continental phylogenetic tree?

Darren M. Crayn¹, Lalita Simpson¹, Theodore R. Allnutt², William J. Baker³, Matt Barrett¹, Gillian Brown⁴, Félix Forest³, Chris Jackson², Lizzy Joyce⁵, Paul J. Kersey³, Mabel Lum⁶, Olivier Maurin³, Todd G. B. McLay⁷, Daniel J. Murphy², Katharina Nargar¹, Hervé Sauquet⁸, Alexander Schmidt-Lebuhn⁹, Kelly A. Shepherd¹⁰, Andrew Thornhill¹¹, Michelle Waycott¹²

¹ Australian Tropical Herbarium, James Cook University, Smithfield, Australia. ² Royal Botanic Gardens Victoria, Melbourne, Australia. ³ Royal Botanic Gardens, Kew, Richmond, UK. ⁴ Queensland Herbarium, Toowong, Australia. ⁵ Ludwig Maximilians University of Munich, Munich, Germany. ⁶ Bioplatforms Australia, Sydney, Australia. ⁷ National Biodiversity DNA Library, CSIRO, Parkville, Australia. ⁸ Botanic Gardens of Sydney, Mt Annan, Australia. ⁹ Centre for Australian National Biodiversity Research, Canberra, Australia. ¹⁰ Western Australian Herbarium, Perth, Australia. ¹¹ University of New England, Armidale, Australia. ¹² State Herbarium of South Australia, Adelaide, Australia

Australia, the world's smallest continent has a globally significant flora comprising over 2,100 genera and 21,000 native species of flowering plants, of which over 90% are endemic. The Genomics for Australian Plants (GAP) Initiative, catalysed by Bioplatforms Australia in partnership with researchers from the Australian State and National Herbaria and Botanic Gardens, aims to develop genomics resources to enhance our understanding of the evolution of this unique flora and support its conservation. GAP Phylogenomics, one of three GAP activity streams, has the long-term goal of resolving the Australian Angiosperm Tree of Life (AATOL) to species level. To date, this inclusive project has brought together over 70 Australian researchers and herbarium staff and partnered with the global Plant and Fundamental Trees of Life project (PAFTOL) to complete AATOL Stage 1 – reconstructing a phylogenetic tree including

at least one species exemplar of nearly 95% of Australian native angiosperm genera sequenced for a common set of hundreds of nuclear markers (using the Angiosperms353 target capture baits). However, because sampling is strongly biased due to being geographically constrained, the range of applications of this continental tree in evolutionary biology is limited

Approximately half of Singapore's native plant diversity resides in a small, 1.64 km² patch of rainforest in Bukit Timah Nature Reserve (BTNR). Between 2019 to 2022, we collected and vouchered a total of 882 angiosperm species from BTNR. Illumina shotgun short-read sequencing was carried out for each species to obtain a minimum of 30Gb of data, followed by genome assembly and gene prediction. For the first stage of the project, we focused our analysis on 499 good quality genomes. A set of 1,000 conserved single-copy genes were used to generate a high-resolution phylogeny of the BTNR species, illustrating that when compared with APG IV, there were differences in the position of Santalales and the relationships within the families in Malpighiales and some orders in the malvids and fabids. Gene predictions allowed us also to study ancestral whole genome duplication events, to look for evidence of introgression and to chart the proteomic diversity present in BTNR.

### S.21.4 Angiosperm evolution and biogeography across the floristically diverse Canary Islands archipelago

Ryan F.A. Brewer¹,²*, Luis Valente¹,², Rampal S. Etienne², Ornela Dehayem Nanwou², Laura van Hoek¹, Marcelino José del Arco Aguilar³, Yurena Arjona⁴, Juli Caujapé-Castells⁵, José María Fernández-Palacios³, Ruth Jaén-Molina⁵,⁶, Louis S. Jay-García⁴, Águedo Marrero⁵, Sara Martín-Hernanz⁷,⁸, Cristina González-Montelongo³,⁹, Jairo Patiño⁴, Stephan Scholz¹⁰, Pablo Vargas¹¹, Frederic Lens¹,¹²

¹ Naturalis Biodiversity Center, CR Leiden, The Netherlands. ² University of Groningen, Groningen, The Netherlands. ³ Universidad de La Laguna. La Laguna, Tenerife, Islas Canarias, Spain. ⁴ Instituto de Productos Naturales y Agrobiología (CSIC), La Laguna, Tenerife, Spain. ⁵ Jardín Botánico Canario ‘Viera y Clavijo’-Unidad Asociada CSIC, Las Palmas
<figure><img src="image_65.png" /></figure>

de Gran Canaria, Gran Canaria, Spain. 6 DNA Bank of the Canarian Flora, Jardín Botánico Canario ‘Vi- era y Clavijo’-Unidad Asociada CSIC, Las Palmas, Gran Canaria, Spain. 7 Universidad de Sevilla, Sevil- la, Spain. 8 Royal Botanical Gardens, Kew, London, UK. 9 TFC Herbarium. Universidad de La Laguna. San Cristobal de La Laguna, Tenerife, Canary Islands, Spain. 10 Jardín Botánico Oasis Wildlife Fuerteven- tura, La Lajita, Fuerteventura. 11 Real Jardín Botánico (CSIC), Madrid, Spain. 12 Leiden University, Leiden BE, The Netherlands. *Corresponding author. ryan. brewer@naturalis.nl

A fundamental characteristic of biodiversity is its un-
even distribution across the Tree of Life. A prominent
example of this is the flora of the Canary Islands,
which comprises many spectacular species-rich ra-
diations and dozens of depauperate, single-species
lineages. Addressing why some lineages have diver-
sified, whilst others have not, requires phylogenom-
ic datasets, which can provide unparalleled insight
into the dynamics governing diversity unevenness.
For example, time-calibrated phylogenetic trees
can be used to estimate dynamic biogeographic
processes (such as rates of speciation, extinction,
and colonisation), allowing us to infer the drivers of
radiations and depauperate lineages alike. Howev-
er, a community-wide phylogenetic dataset for the
Canarian flora that would allow for such analyses is
lacking. Here, we present a time-calibrated molec-
ular phylogeny including over 800 species of native
Canary Islands flowering plants (~60 % of the native
flora), constructed using hybrid capture-based tar-
get enrichment of the angiosperm-wide 353 bait
set. We sequenced the majority of species and lin-
eages that make up the native angiosperm flora of
the archipelago and, to estimate the colonisation
and branching times of the Canarian lineages, in-
tegrated the sequences into a broader, time-cali-
brated angiosperm phylogeny based on the same
angiosperm-353 gene set. Crucially, to provide an
estimate of colonisation times, we also sampled the
closest mainland relatives of each lineage. We also
present an estimated number of independent col-
onisation events for all native angiosperm genera
of the archipelago, inferred from the phylogenetics
literature, and refined using our phylogenetic data.
From the temporal information contained within the
molecular phylogeny, we generate a novel recon-
struction of the biogeographic history and temporal
diversity dynamics of angiosperms in the Canary
Islands. By combining biogeography, ecology, and
evolution, our analyses present novel insights into
the factors underlying the community dynamics of
the near-complete flora of a large, floristically di-
verse oceanic archipelago.

S.21.5 Phylogenetic analyses
of entire regional flora using
Angiosperms353 sequences
data

Sébastien Miche¹², Charles Pouchon²,
Camille Christe², Nicolas Wyler², Mathieu
Perret¹²

1 Department of Plant Sciences, University of Geneva, Genève 4, Switzerland. 2 Conservatory and Botanical Garden of Geneva, Pregny-Chambésy, Switzerland

Accurate knowledge of the phylogenetic relation-
ships among the species composing the regional
biota is crucial to understand how species were
assembled and how much phylogenetic diversity
they represent. However, phylogenetic information
available for local species communities is still limit-
ed because of the poor resolution and uncomplete
sampling of the tree-of-life at the species-level.
Here, we demonstrate the feasibility of using Angio-
sperms353 target-enrichment and high-through-
put genome sequencing on both fresh and historic
DNA to estimate phylogenetic relationships among
all species composing the regional flora of the Swiss
plateau. The analysis of over 1300 species provides
a more resolved and complete tree than available
synthetic or plastid-based phylogenies, especially
within complex families (e.g. Cyperaceae, Oroban-
chaceae, Poaceae). This new genomic reference for
swiss plants points to several disagreements with
the current plant classification and provides a new
framework to assess the evolutionary dynamics of
a complete regional flora. Our results bring new in-
sights into the consequences of habitat conversion
on phylogenetic diversity and the identification of
areas that should be prioritized for long-term con-
servation strategies.
# S.22 GLOBAL MYRTACEAE SYSTEMATICS: PURE AND APPLIED PERSPECTIVES FOR MANAGING AND CONSERVING THE EARTH'S PLANT DIVERSITY

## S.22.1 Fruit evolution in Eugenia (Myrteae, Myrtaceae), with taxonomic implications in one of the world's largest tree genera

Fiorella F. Mazine¹, Karinne S. Valdemarin², Mariana Andreotti¹, Eve Lucas³ & Vinicius C. Souza²

1 Universidade Federal de São Carlos, campus Sorocaba - Sorocaba, São Paulo, Brazil. 2 Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo - Piracicaba, São Paulo, Brazil. 3 Royal Botanic Gardens Kew - Richmond, UK.

Tropical forest habitats are characterized by the prevalence of plants bearing fleshy fruits dispersed by animals. In South America, the genus *Eugenia* stands out, with a high number of species and serving as a significant year-round producer of fleshy fruits. The evolution of fleshy fruits is considered a potential key innovation in the hyper-diversification of subtribe Myrteae and the large genus *Eugenia*. Our investigation focused on the hypothesis that variation in fleshy fruit traits within *Eugenia* is closely linked to infrageneric lineages. We aimed to determine if specific species groups display distinct patterns of fruit traits and whether these traits have evolved to enhance reproductive success by either attracting specific dispersers or reducing seed predation. Results revealed substantial variability in *Eugenia* fruit traits, with discernible trends within infrageneric groups. The predominant exocarp colour in sampled *Eugenia* fruits were dark purple and red, contrasting with a higher probability of ancestral colours being yellow. Ripened exocarp colour is relatively strongly associated with taxonomic sections, suggesting potential common ancestry. Larger-fruited species are rarer and concentrated in early diverging clades within *Eugenia*, offering a potentially informative taxonomic feature for these groups. The number of seeds, a labile trait within

*Eugenia*, was commonly recorded as one, but early diverging clade species tend to produce fruits containing more than one seed. Pulp ratio exhibited a stronger association with taxonomic sections, suggesting that species from more recently diverging clades invest less energy in pulp production and instead allocate more resource to seed size. Our findings suggest that variation in fleshy fruit traits in *Eugenia* can help define infrageneric lineages. Specific groups of *Eugenia* species display unique patterns of fruit traits, and our evidence suggests that these traits may have evolved to maximize reproductive success by either attracting specific dispersers or minimizing seed predation.

## S.22.2 The relationship between environment and reproductive traits in the clove genus (Syzygium-Myrtaceae)

Eve Lucas¹, Max Fontaine¹,², Low Yee Wen¹,³, Wei Han Fang⁴, Matilda Brown¹

1 Royal Botanic Gardens Kew, Richmond, Surrey, UK. 2 University of Bath, UK. 3 Singapore Botanic Gardens, 1 Cluny Road, Singapore. 4 National Taiwan University, Taipei, Taiwan

Syzygium (Myrtaceae), is one of the most diverse tree genera globally, encompassing economically significant species such as clove, lilly pilly, and water apple. Its natural habitat spans Southeast Asia, Southern Asia, Australia, and the Pacific, with most species falling within *Syzygium* subgenus *Syzygium*. Despite its economic importance, the taxonomic complexity of the genus, coupled with limited knowledge about its evolution and ecology, poses challenges to downstream activities such as conservation. Our study focuses on a representative sample of *Syzygium* subgenus *Syzygium*, leveraging reproductive traits, geolocation data, and climate information. Our aim is to identify the key environmental
<figure><img src="image_66.png" /></figure>

variables influencing floral and fruit diversity within the genus. Considering the relationships among biotic and abiotic factors, we explore these variables within a phylogenetic context to discern patterns independent of and influenced by the environment. Our investigation recorded 12 continuous and 13 discontinuous traits related to flowers and fruits from the sample species. To analyse climate variation, we extracted 19 CHELSA bioclimatic variables for all GBIF *Syzygium* occurrences. Mixed PCA plots were constructed to independently assess trait and environmental Principal Components. To understand the evolution of each trait cluster, we compared Brownian Motion and Ornstein-Uhlenbeck models of evolution based on a pruned version of the most comprehensive available phylogenetic hypothesis. Phylogenetic linear modelling was employed to observe the interplay between the environment and the main axes of trait variation while considering the evolutionary relationships between species. Our results highlight temperature, precipitation, and seasonality as the primary independent climatic drivers influencing Syzygium distribution. We found that flower/fruit size contributes more to morphological variation than any other biotic traits examined. Weak correlations were identified between flower/fruit size, inflorescence architecture, fruit colour, and climate. All biotic traits better fit the Ornstein-Uhlenbeck model suggesting that these characteristics are evolving under natural selection rather than randomly.

## S.22.3 A review of eucalypt research from the last decade (2014-2024)

Andrew H. Thornhill¹

1 N.C.W. Beadle Herbarium, University of New England, Armidale, NSW, Australia

Much progress has been made in the phylogenetic analysis of the eucalypts (*Angophora*, *Corymbia*, and *Eucalyptus*). This presentation aims to summarise the progress and now controversies that have occurred in eucalypt generic classification since the previous International Botanical Congress in 2017. Two large-scale phylogenies of the group have been published and a new genus, *Blakella*, has been proposed to deal with the paraphyly of *Corymbia*. The eucalypt fossil record and our current understanding of the biogeography will be discussed. New species have been described from most Australian

states, while other research suggests that some eucalypt species should be lumped. A new edition of the eucalypt identification key Euclid was published in 2019 but ways of creating new editions are now limited. Ways to solve this problem are discussed.

## S.22.4 Exploring the timing of environmental shifts in response to trait evolution: a case study in Myrteae (Myrtaceae)

Thais Vasconcelos¹, James Boyko¹

1 Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI, USA

The widespread convergence of plant traits in certain environments indicate that generalities exist for how plants diversify in space. However, because evolution and environments are dynamic, not all species are fully adapted to their environment at all times. A consequence of this is that infrequent trait-environment combinations – that is, plant traits that appear in environments where they may not be optimal—is also a common feature in nature. The presence of these infrequent combinations can be harnessed to test timing of trait evolution in relation to environmental shifts. Specifically, when analyzed in a phylogenetic context they might help indicate whether traits evolve prior to (as in expations) or after (as in adaptation) an environmental shift. Here, we demonstrate this in the context of leaf traits and biome shifts in Myrteae (Myrtaceae). We use a subset of 221 species with dry leaf mass/area (LMA g/cm²) data measured from herbarium specimens and trait evolution analyses in a recently generated phylogeny for the group. Biome type and LMA appear correlated, with low LMA lineages being more common in closed-canopy biomes. Low LMA in closed-canopy biomes is recovered as the most likely root state in the group. Transition rates from this state to low LMA in open-canopy biomes are practically zero, meaning that the only route to transition to open-canopy biomes is by evolving high LMA first. Similarly, to transition from open-canopy back to closed-canopy, lineages have to evolve low LMA before a shift. These preliminary results support the idea that trait evolution precedes and may facilitate environmental shifts, at least for this trait and set of species.
S.22.5 Assembling the
genome of rātā Moehau
and applications for other
New Zealand Metrosideros
(Myrtaceae)

Jessica M. Prebble¹, Natalie Forsdick²,
Thomas Buckley², Rob Smissen¹, Peter
Heenan¹, Peter Bellingham¹, Alex Verry¹,
Connor Watson¹, Dukchul Park², Ngāti Kuri³

1 Manaaki Whenua - Landcare Research, Lincoln, New Zealand. 2 Manaaki Whenua - Landcare Research, Private Bag 92170 Auckland Mail Centre Auckland, New Zealand. 3 Ngāti Kuri Trust Board, Ngatai, RD4, Kaitaia, New Zealand

The 12 *Metrosideros* (Myrtaceae) native to the New Zealand archipelago are facing a growing number of threats, particularly since the arrival of the pathogen myrtle rust (Austropuccinia psidii) in 2017. Despite their iconic status (e.g. Pōhutukawa *M. excelsa* known as the New Zealand Christmas tree) we have surprisingly little genetic data to help us understand how diversity is partitioned across the landscape for most species. One of the most threatened species is rātā Moehau (*M. bartlettii*), a critically endangered tree found only in the far north of New Zealand. At the last count only 14 trees were found in the wild. In conjunction with the iwi (tribe) Ngāti Kuri we have assembled a genome of rātā Moehau. This assembled genome forms the basis of multiple studies in the genus, e.g. resequencing almost the entire wild population of rātā Moehau, plus representatives of additional closely related species. At the same time, we are using the assembled genome to develop new low copy genetic markers and are gathering a dataset of as many New Zealand *Metrosideros* species as we can to sequence using amplicon sequencing. The end goal is an understanding of how the genetic diversity of each New Zealand *Metrosideros* species is distributed in space, with a particular focus on modelled refugia in the face of climate change and projected myrtle rust spread, to help prioritise conservation effort.

S.22.6 Digital approaches
in taxonomy: surfacing
datasets from herbarium
specimens and images to
treat a species complex in
Myrcia (Myrtaceae)

Paulo Henrique Gaem¹,² Eve Lucas³,
Fiorella Fernanda Mazine⁴, Maria do
Carmo Estanislau do Amaral¹

1 University of Michigan, Ann Arbor, MI, USA. 2 Universidade Estadual de Campinas, Campinas, SP, Brazil. 3 Royal Botanic Gardens, Kew, Richmond, Surrey, UK. 4 Universidade Federal de São Carlos, Sorocaba, SP, Brazil

Herbaria are the most important source of informa-
tion for taxonomic work. Facilities and technologies
available today, such as digitisation of collections
and herbarium DNA sequencing, can help accelerate
taxonomic decisions. Species complexes are a ma-
jor factor preventing a better understanding of plant
diversity in the tropics. In this context, we employed a
multi-source pipeline to address limits among taxa of
the *Myrcia neoobscura* species complex (Myrtaceae)
using herbarium specimens. We collected morpho-
metric traits from high-resolution images and anal-
ysed them with a clustering analysis, resulting in twelve
morphological groups. We subsequently tested these
groups with phylogenomics using molecular data ob-
tained from herbarium specimens. Congruence be-
tween morphology and phylogenomics was observed
in the following: *Myrcia marliereana*, *M. neoobscu-
ra*, and *M. neoriedeliana*, as currently circumscribed,
represent two entities each, and *M. excoriata* can be
split in three entities. We also investigated species
geographic distributions and phenological patterns
using herbarium specimens and their labels. The two
species today recognised under *M. neoriedeliana* and
*M. neoobscura* differ in flower seasonality, while two
of the taxa currently under *M. excoriata* differ in both
geographic distribution and flowering phenophase.
The final species delimited in this work are morpho-
logically diagnosable and geographically structured,
and most of them are monophyletic according to the
obtained phylogenetic reconstruction. The success-
ful results of this work are based on the high-quality
data obtained from museum specimens, and other
herbarium-based investigations of species complexes
are encouraged to accelerate the much-needed
taxonomic resolutions in the tropics.
# S.23 INTEGRATING CONSERVATION BIOLOGY AND SOCIETY ENGAGEMENT TO ENHANCE PROTECTION OF AT RISK FLORA. SESSION 1

## S.23.1 A survey of flora and habitat diversity in three cultural heritage sites of central and southern Italy

Giulia Albani Rocchetti¹, Thomas Abeli¹, Giulia Caneva¹

1 Department of Science, Roma Tre University, Rome, Italy.

Several scientific studies highlight that cultural heritage sites, e.g., monuments and sacred sites, often represent refuge sites for local flora and fauna and can constitute important ecological corridors and biodiversity hot spots. Hence, protected cultural heritage sites can play a key role in biodiversity conservation at the global scale, especially for those situated in environments modified by anthropogenic activities. To ensure adequate management of these sites to enhance and conserve biodiversity, in-depth knowledge of the flora, vegetation and the nature-man relationship are essential elements to consider. This research aims to provide the first characterization and analysis of the flora and habitats of three Italian sites of the Cultural Route of the Council of Europe "Aeneas' route". This research is also aimed at increasing citizens' awareness of the importance of maintaining biodiversity and analyzing the relationships between natural and historical characteristics of these important contexts in southern Italy. Currently, field surveys are being conducted in the following sites: 1) The archaeological Park of Cuma is a site of great archaeological and cultural importance, with areas of great naturalistic and conservation interest. Here, 160 different taxa and two interesting forest communities formed by previous plantations now naturalized were founded. 2) Sanctuary of Sol Indiges, Torvaianica; to date, the site is rich in taxa (more than 180 species), with species of conservation interest (e.g., orchids) and high biodiversity and community patterns. 3) The archaeological area of Portus presents a high naturalistic, landscape, historical and cultural interest. Here, more than 160 different wild and cultivated

taxa, and different vegetation patterns -including wetland and riparian - were found. Here, preliminary data useful for the next characterization, valorization, and conservation of the flora and vegetation of the above-listed sites are provided. The application of results includes the site management implementation and the planning of conservation actions.

## S.23.2 Rare and endemic plant conservation: insights from the East Mediterranean experience

Magda Bou Dagher Kharrat¹, Carole Saliba¹, Rhea Kahale¹, Sonja Yakovlev¹, Thierry Robert¹

1 Faculty of Science, Saint Joseph University of Beirut and Mediterranean Facility (EFIMED) European Forest Institute - Barcelona Office Sant Pau Art Nouveau Site, Sant Leopold Pavilion, Barcelona, Spain

The Mediterranean Basin is considered to be one of the most biodiverse regions in the world and an important site of floral exchange and active plant speciation. Lebanon, a micro-hotspot for plant biodiversity in the Mediterranean Basin is characterized by the coexistence of plants with diverse biogeographical origins and a large number of narrow endemic taxa. It clearly exhibits differentiated center of endemism. Topographical relief and sharp climatic contrasts within a small geographical area may have driven micro-evolutionary diversification processes of newly evolved species while water availability was critical for the long-term persistence of ancient lineages in refuge areas of smoother topography. As natural habitats continue to be lost and degraded, many plant species are becoming increasingly threatened especially endemic plant species that are usually more vulnerable to anthropogenic threats and natural changes. Therefore, they hold a higher extinction risk. The preservation of these species is a major concern on a worldwide context. Our research group has carried out for the last few years
<figure><img src="image_67.png" /></figure>

an interdisciplinary, integrated approach to the conservation of threatened plants of the Lebanese flora and to ecosystem restoration. Investigations on plant distribution, systematic relationships, autoecology, genetic structure, and some plant-animal species interactions were conducted in order to plan conservation activities. My talk will focus on Lebanese endemic Irises. Four of the 7 Iris studied are classified as "Endangered" and 2 as "Critically Endangered". Knowing what taxonomic units need to be preserved and how unique they are is a prerequisite to any conservation action. Since rescue from possible extinction could be performed through the reinforcement of populations, defining species and differentiating taxa is crucial in order to define conservation units. For this purpose, molecular and cytogenetic studies were conducted, targeting different species in need of in-situ and ex-situ conservation.

### S.23.3 Ecology and conservation of cliff-plant communities under increasing climatic and human pressures

Martí March-Salas¹,²; Felipe Morales-Armijo³; Juan Lorite⁴

¹ Plant Evolutionary Ecology, Faculty of Biological Sciences, Goethe University Frankfurt. Frankfurt am Main, Germany. ² Area of Biodiversity and Conservation, Department of Biology and Geology, Physics and Inorganic Chemistry, University Rey Juan Carlos-ESCET, Móstoles, Madrid, Spain. ³ Facultad de Ciencias Forestales, Universidad Autónoma de Nuevo León, Victoria, A.P. 41, Linares, Nuevo León, Mexico. ⁴ Department of Botany, Faculty of Sciences, University of Granada, Granada, Spain

Cliffs are home to a large diversity of endemic and endangered plant species and millennial-old trees that are currently facing increasing threats from climate change and recreational climbing. In recent years, rock climbing has become very popular, with annual increases of 15-20% in the number of climbers. Rock climbing is known to damage plant communities and other organisms such as birds, lizards or snails. However, the origin of the climbing impact remain largely unknown. Climbing impact sometimes compels conservation managers to make insecure or even inappropriate decisions within a framework of growing conflicts among stakeholders. But the climbing community has expressed its

willingness to contribute to cliff preservation, with various climbing associations focused on promoting sustainable climbing. We carried out a study investigating the origin of the climbing effects on cliff flora involving the local community. In primal and unaltered cliffs of El Potrero Chico (Mexico), we installed new climbing routes to unravel whether the greatest climbing impact is produced in an initial phase due to the installation (opening) of the route or rather due to increasing climbing frequency. Local climbers actively contributed to create the new routes and posteriorly climbed them simulating the post-opening climbing effect. We found that the opening of the climbing route produced the greatest negative impact on cliff flora, and also promoted the loss of individuals from the surroundings of the route. However, successive post-opening climbing have little effects on cliff flora. These findings clearly evidence the need to consider existing cliff vegetation before developing new climbing routes, and that managers should focus on this rather than closing existing climbing areas. Given the high complexity of study cliff ecosystems, promoting awareness on its biodiversity and protection needs to the local community will contribute to its preservation.

### S.23.4 Local involvement for endemic floristic species conservation: case study of the Kirindy forest Morondava - Madagascar

Andriaharimalala T.¹, Ramakarison N. G.², Razanamaro O.H.M.³

¹ Centre National de recherches sur l'Environnement, Ministère de l'Enseignement Supérieur et de la Recherche Scientifique, Madagascar. ² Centre National de Formation, d'Etudes et de Recherche sur l'Environnement et la Foresterie, Ministère de l'Environnement et du Développement Durable, Madagascar. ³ Parc Botanique et Zoologique de Tsimbazaza, Ministère de l'Enseignement Supérieur et de la Recherche Scientifique, Madagascar

This study focuses on the crucial role played by the local community in safeguarding the endemic floristic species within the Kirindy Forest in Morondava, Madagascar, where several tree species face the imminent threat of extinction. Various stakeholders are actively combating deforestation and endeavoring to enhance the protection of unique species such as Dalbergia sp., Commiphora sp., Givotia
<figure><img src="image_68.png" /></figure>

madagascariensis, Cordyla madagascariensis, and Diospyros sp. The primary aim of this research is to evaluate and promote community engagement in the conservation of these distinctive botanical treasures. The methodology involves data collection through surveys and interviews with both the local population and managers, focusing on the utilization of these species. Additionally, in-depth interviews and field observations are employed to gather insights into the knowledge, attitudes, and practices of the local community, identifying traditional wisdom and indigenous practices related to biodiversity. The study results encompass a comprehensive assessment of the local population's knowledge and attitudes toward conserving endemic floristic species, proposing solutions for ensuring the sustainability of these species, and exploring traditional practices conducive to preservation. The outcomes will contribute to formulating recommendations for tailored awareness programs targeted at the local community. Furthermore, the study will underscore the implications and commitments of the local population in the conservation and protection of the floristic biodiversity of the Kirindy Forest, emphasizing the development of sustainable strategies for safeguarding their natural heritage.

## S.23.5 Conservation strategies for large old trees to promote natural forest restoration and climate-change mitigation

Alfredo Di Filippo¹,²,³, Andrea Caggegi¹,²

1 DAFNE, Università della Tuscia, Viterbo, Italy. 2 AgriTech - National Centre for Technology in Agriculture, Italy. 3 National Geographic Society, Washington DC, USA

Primary forests, including old-growth forests, have a prominent role in biodiversity conservation. Furthermore, they represent a consistent repository of carbon in tree biomass and soil, making them critical regulators of the carbon cycle. Their ecological integrity strengthens their climate-change mitigation potential by fostering ecosystem stability as a C sink. Old trees are the most charismatic element of old-growth forests, harbouring large quantities of the overall biomass and contributing to forest biodiversity with unique arrays of microhabitats. We present the unique traits characterizing multi-century beech trees in a network of old-growth for-

ests in the UNESCO Site 1133. We describe how traits change along environmental gradients and quantify their contribution to the forest carbon stock and sequestration, as well as the quantity and quality of biodiversity-hosting microhabitats. Tree-ring cores collected along the whole trees served to quantify tree conservation status in terms of response to climate change in the last decades. Old trees features were compared with data on exceptional tree distribution throughout managed landscapes gathered in a citizen science project promoted within the National Geographic-funded project "Old But Gold: Restoring old-growth forests to build effective climate-change mitigating landscapes". Comparing natural and managed forests will help quantify the potential of human-altered landscapes to host old trees and the contribution of natural forest restoration to climate mitigation and biodiversity conservation.

## S.23.6 Pampa Singular: integrative conservation on subtropical grasslands of South America

João Iganci¹*, Gustavo Heiden², Josimar Külkamp¹, Daiane Vahl¹, Emanuel Scherdien¹, Alessandra Menezes¹, Mauricio Bonifacino³, Eimear Nic Lughadha⁴

1 Universidade Federal de Pelotas, Brazil. 2 Embrapa Clima Temperado, Pelotas, Brazil. 3 Universidad de La República, Montevideo, Uruguay. 4 Royal Botanic Gardens, Kew, UK. *joaoiganci@gmail.com

The Pampas is one of South America's major grassland ecosystems, extending from northern Argentina to Uruguay and southern Brazil. In addition to natural grasslands, rocky outcrops, coastal vegetation, swampy areas, savannas, and small patches of dry forests increase landscape heterogeneity and are home to a remarkable diversity of plant species, of which 5% are endemic to the Pampas. Cattle grazing was the dominant economic activity in the area until the late 20th century, and the natural grasslands were used in a more sustainable manner. However, the growth of agriculture, silviculture, and mining throughout the Pampas in recent decades has resulted in significant habitat loss and accelerated habitat fragmentation. Pampa Singular is an integrative project that focuses on under-
<figure><img src="image_69.png" /></figure>

standing biodiversity in the Pampas, as well as the conservation of unique landscapes and rare plant species. We produced endemic flora species inventories and searched for crop wild relatives from the Pampas. Furthermore, science outreach initiatives were designed to raise awareness in the local population and to promote science and conservation for future generations. Most plant species endemic to the Pampas have never been assessed for their

conservation status (extinction risk) and many lack sufficient data to be assessed. We used the Rapid Least Concern method to identify species that were not threatened and focused our efforts on likely threatened species. We mapped the most diverse areas for endemic species and for crop wild relatives, comparing historic and current species distributions taking into account land conversion to economic uses.

# S.24 THE IMPACT GENOME SIZE AND CHROMOSOME EVOLUTION ON THE ARCHITECTURE OF THE GENOME

## S.24.1 Challenges and lessons learnt from a giant plant genome: the European mistletoe (Viscum album L.)

Lucía Campos-Domínguez¹², Alexandros Bousios³, Max Brown⁴, Robin Burns⁵,
Wellcome Sanger Institute Tree of Life programme, Wellcome Sanger Institute Scientific Operations: DNA Pipelines collective, Tree of Life Core Informatics collective, Darwin Tree of Life Consortium, Ian Henderson⁵, Ilia Leitch⁶, Alex D. Twyford⁷

¹Centre for Research in Agricultural Genomics Consejo Superior de Investigaciones Científicas-Instituto de Recerca i Tecnologia Agroalimentàries-Universitat Autònoma de Barcelona-Universitat de Barcelona, Barcelona, Spain. ²Ashworth Laboratories, Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, UK. ³School of Life Sciences, University of Sussex, Brighton, UK. ⁴School of Life Sciences, Anglia Ruskin University, Cambridge, UK. ⁵Department of Plant Sciences, Downing Street, University of Cambridge, Cambridge, UK. ⁶Comparative Plant and Fungal Biology Department, Royal Botanic Gardens, Kew, Richmond, Surrey, U.K.

The European mistletoe (Viscum album) is an obligate hemiparasitic plant from the Santalaceae family. Although it is a well known plant for its many uses and traditions, evolutionary and genomic studies on mistletoe are rare due to its haploid genome size, which can vary from 85 Gbp up to 105 Gbp (more than 30 human genomes). This makes mistletoes one of the

eudicot genera with the largest genomes. We have sequenced, assembled and curated the Viscum album genome to generate the largest high-quality, chromosome-level genome published to date. Moreover, here we present preliminary results not only on the genome assembly data but on the analysis of the repetitive fraction of the genome, including TE distribution as well as telomere and centromere repeat analyses. Our efforts are resulting in the first in-depth insights on a giant genome structure, which represents an invaluable resource for studies on the evolutionary processes underlying the evolution of genome obesity.

## S.24.2 Interactions between cytogenetic diversity and habit - insights from neotropical orchids

Roseane R. dos Santos¹, José J. Amorim-Silva¹, Juliano S. Cabral², Ana P. Moraes³

¹Universidade Federal do ABC, São Bernardo do Campo, Brazil. ²University of Birmingham, Birmingham, UK. ³Universidade Estadual Paulista, IBB, Botucatu, Brazil

The relationship between cytogenetic and ecological data is a classical hypothesis. Recently, this subject was poorly analyzed within an evolutionary framework using phylogenetic comparative methods (PCM). To address this gap, we investigated the association between cytogenetic data and habitat using the subfamily Epidendroideae (Orchidaceae) as a model through PCM. The chromosome number (CN) and genome
<figure><img src="image_70.png" /></figure>

size (GS) data were organized into an online database (http://orchidcountsdb.epizy.com/) and a new phylogenetic tree was constructed based on four markers encompassing 1,754 species. Habit information was surveyed for all species with cytogenetic data. The CN varied 24x and presented a low phylogenetic signal (λ=0.53), while GS varied 119x and presented a high phylogenetic signal (λ=0.95). The mode and tempo of evolution suggest that both CN and GS show punctual evolution (k=0.34), with long branches contributing more to the evolution of both characters (δ=3.00). When analyzing each tribe individually, Cymbidieae stands out as an interesting exception. This tribe shows adaptive radiation for CN and GS (k = 0 and 0 / δ = 0.46 and 0.31, respectively), and CN presents a high phylogenetic signal (λ=0.89). The OU evolutionary model, suggesting a response to stabilizing selection, was considered the best model for CN in the subfamily and in individual tribes as well, while BM was the best for GS. Once again, the exception is Cymbidieae, which had EB as the best model for both characters, reinforcing the suggestion of adaptive radiation. Based on these results, GS is more suitable for performing macroecological analysis, while PCM using CN will function as an ordinary test. Considering GS, small GS is associated with an epiphytic habitat (p=0.00067). In conclusion, GS is associated with habit at higher taxonomical levels, such as subfamily, while CN, is associated with ecological traits, it should be true at lower taxonomic level.

### S.24.3 The impact of repetitive DNA in the evolution of fern genomes

Pol Fernández¹², Ilia J. Leitch³, Andrew R. Leitch⁴, Lisa Pokorny⁵,³, Oriane Hidalgo³, Maarten J. M. Christenhusz³, Rémy Amice⁶, David Bruy⁷,⁸, Jaume Pellicer¹,³

1 Institut Botànic de Barcelona (IBB), CSIC-CMCNB, Passeig del Migdia s.n., Parc de Montjuïc, Barcelona, Spain. 2 Facultat de Farmàcia i Ciències de l'alimentació, Campus Diagonal, Universitat de Barcelona, Barcelona, Spain. 3 Royal Botanic Gardens, Kew, Richmond, UK. 4 School of Biological and Behavioural Sciences, Queen Mary University of London, London, UK. 5 Real Jardín Botánico (CSIC), Madrid, Spain. 6 Independent researcher, Nouméa, Nouvelle-Calédonie. 7 AMAP, IRD, Herbier de Nouvelle-Calédonie, Nouméa, Nouvelle-Calédonie. 8

UMR AMAP, Université Montpellier, IRD, CIRAD, CNRS, INRAE, Montpellier, France

Genomic architecture in ferns stands out significantly from that of other plant lineages. Ferns exhibit a unique response to whole genome multiplication (WGM), deviating from the typical diploidization pattern observed in angiosperms. Instead, ferns tend to accumulate chromosomes and trigger the silencing of newly acquired gene copies following WGM. Consequently, ferns display higher mean chromosome numbers (n=61) compared to angiosperms (n=17). Nevertheless, while average fern genome sizes (IC=12.11 Gbp) are larger when compared to angiosperms (IC=5.13 Gbp), the underlying mechanisms responsible for such differences remain unclear. Certainly, the contribution of repetitive DNA in driving shifts in genome size is well studied in angiosperms, but needs to be further explored in ferns. This study seeks to address this knowledge gap by conducting a comprehensive comparative analysis to identify and quantify the main types of repetitive DNA sequences in 50 fern species. The sampling covers a genome size range varying over 222-fold (0.72-160.4 Gbp), including the largest eukaryote genome recently discovered in the fern *Tmesipteris oblanceolata* (IC=160.4 Gbp). The central focus of this research is to enhance our understanding of the genomic processes contributing to the unique characteristics observed in fern genomes, shedding light on the broader evolutionary implications for plant genome size. The composition of the repetitive DNA fraction of the genome for each species has been identified and quantified through low-coverage genome skimming sequence data analysed with the RepeatExplorer2 pipeline. Overall, our results show that fern genomes have a more heterogeneous genome landscape than angiosperms and, unlike them, they show a positive correlation of repetitive elements with genome size. Future studies will focus on identifying the particular role of specific families of repeats that are enriched or depleted in fern genomes, while diving deeper into the relationship between the accumulation of chromosomes and its implication on genome composition.
<figure><img src="image_71.png" /></figure>

## S.24.4 The Crocus Chronicles: Decoding the Triploid Puzzle of Clonal Saffron Crocus

Abdullah El-nagish¹², Ludwig Mann¹, Seyedeh Sanam Kazemi Shahandashti³,⁴, Dörte Harpke⁵, Zahra Nemati⁵, Maximilian W. Schmidt⁶, Susan Liedtke¹, Frank R. Blattner⁵, Björn Usadel³,⁴, Tony Heitkam¹,⁷

1 Faculty of Biology, Institute of Botany, Technische Universität Dresden, Dresden, Germany. 2 Botany and Microbiology Department, Faculty of Science, Sohag University, Sohag, Egypt. 3 Institute of Biological Data Science, Heinrich-Heine Universität Düsseldorf, Düsseldorf, Germany. 4 IBG-4 Bioinformatics, Forschungszentrum Jülich, Jülich, Germany. 5 Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, Germany. 6 Department of Grapevine Breeding, Hochschule of Gelsenheim University. 7 Institute of Biology, NAWI Graz, Karl-Franzens-Universität, Graz, Austria

Saffron crocus (Crocus sativus L.), a sterile triploid (2n = 3x = 24), is a clonally propagated crop grown for the production of saffron, the highest priced spice of the world. The evolutionary origin of the triploid C. sativus was largely unknown, but debated since the early 20th century. Recent cytogenetic and comparative next-generation sequencing approaches pointed to ancient Greece as a point of origin for saffron and concluded that C. sativus is an autotriploid species solely derived from heterogeneous diploid cytotypes of C. cartwrightianus (Schmidt et al. 2019, Nemati et al. 2019, reviewed in Kazemi-Shahandashti et al. 2022). Here, we target the processes before and after emergence of triploid saffron crocus. With this, we can look into the past, present and future of this clonal line: (1) **The past: How is chromosomal variability in the progenitor C. cartwrightianus?** We detected large differences in haplotype variability among chromosomes, suggesting that some C. cartwrightianus chromosomes have obtained a higher genetic diversity across the Mediterranean than others. This haplotype diversity is fixed in saffron's karyotype, a testimony to the genetic variability of C. cartwrightianus 5000 years ago. (2) **The present: Are there signs of somaclonal variability in the saffron clone?** By comparing triploid saffron accessions across the globe, we detect chromosomal variability in three independent instances. We conclude that several saffron lineages evolved somaclonal-

ly after emergence of triploid saffron crocus. These saffron lineages have likely spread and are retained by vegetative propagation. (3) **The future: Can the global cultivation of the saffron crocus clone serve as a model for the epigenetics of adaptation?** As the basis for comparative and epigenetic analyses, we are assembling reference genomes of the triploid saffron crocus and the diploid progenitor C. cartwrightianus. We show the progress of sequencing, assembly and chromosomal anchoring.

## S.24.5 Repetitive DNA elements reveal contrasting evolutionary responses to the polyploid genome shock hypothesis in Brachypodium grasses

María Ángeles Decena¹², Rubén Sancho¹,²,³, Luis A. Inda¹,⁴, Ernesto Pérez-Collazos¹,², Pilar Catalán¹,²

1 Escuela Politécnica Superior de Huesca, Universidad de Zaragoza, Carretera de Cuarte, km 1, 2071, Huesca, España. mdecena@unizar.es, rsancho@unizar.es, ernextop@unizar.es, lainda@unizar.es, pcatalan@unizar.es. 2 Grupo de Bioquímica, Biofísica y Biología Computacional (UNIZAR), Universidad Asociada al CSIC, España. Zaragoza, España. 3 Estación experimental Aula Dei-CSIC. Zaragoza, España. 4 Instituto Agroalimentario de Aragón-IA2 (Universidad de Zaragoza-CITA), Zaragoza España

The Brachypodium grass species serve as model plants for studying the functional genomics of grass crops, and for elucidating the origins of allopolyploidy and perrenniality in monocots. However, significant variations exist in genome sizes among different Brachypodium diploid and polyploid lineages. To explore the composition, abundance, and phylogenetic significance of repetitive elements in these lineages, we utilized low-pass genome sequencing data from 44 representatives. Our study aimed to test the potential mechanisms and consequences of the "polyploid genome shock hypothesis" (PGSH) in three distinct evolutionary scenarios, analyzing repeat and genome size variations in Brachypodium allopolyploids. Our findings revealed a 3.3-fold difference in the proportion of the genome covered by the repeatome, ranging from 20.77% in *B. stacei*-2x to 67.97% in *B. mexicanum*-4x. Changes in genome sizes were attributed to gains or losses in repeat elements. The most prevalent repeat elements in the Brachypodium genomes were LTR-Retand and Tekay retrotransposons.
<figure><img src="image_72.png" /></figure>

Repeatome phylogenetic networks exhibited high con-
gruence with plastome, nuclear rDNA, and transcrip-
tome trees, distinguishing ancestral outcore lineages
from recently evolved core-perennial lineages. The
rDNA 5S graph topologies aligned well with ploidy levels
and types of subgenomes of *Brachypodium* polyploids.
The core-perennial *B. sylvaticum*-2x displayed a large
repeatome, indicative of a post-polyploid diploidized
origin. Our study evidenced that expansions and con-
tractions in the repeatome accounted for three con-
trasting responses to PGSH: the exacerbated genome
expansion of the ancestral allotetraploid *B. mexicanum*
was a consequence of chromosome-wide prolifer-
ation of TEs and not of WGD, the additive repeatome
pattern of young allotetraploid *B. hybridum* of stabilized
post-WGD genome evolution, and the genome shrink-
age of recent core perennials polyploids (*B. pinnatum*,
*B. phoenicoides*) of repeat losses through recombina-
tion. Our analyses have contributed to disentangling
the evolution of the repeatome and the genome size
variation of model *Brachypodium* grasses.

S.24.6 A comparative look
at genome fractionation in
pteridophytes

Sylvia P. Kinosian¹, Fay-Wei Li², Michael S. Barker¹

1 Department of Ecology and Evolutionary Biolo-
gy, University of Arizona, Tucson, AZ, USA. 2 Boyce
Thompson Institute, Ithaca, NY, USA

Genetic variation created by whole genome dupli-
cation (WGD) events can provide beneficial genetic
variation for evolution to act upon. However, polyploid
genomes comprise many, sometimes unnecessary,
duplicated genes. The loss of these duplicates is part
of the process of diploidization. One mechanism of
diploidization is fractionation, where genes are lost
or silenced in one or both homoeologs. Fractionation
structurally and functionally alters the genome as only
a subset of duplicated genes is retained. This affects
the amount of genetic variation present following
diploidization, influencing how a lineage will be able
to evolve. Despite its evolutionary importance, little
is known about how fractionation occurs in different
lineages of land plants, particularly in ferns and lyco-
phytes (pteridophytes). In angiosperms, fractionation
is thought to proceed quickly, mainly by gene loss.
Previous work suggests that genes may be silenced
rather than lost in pteridophyte genomes, and chro-
mosomes are retained following WGD. We use newly
available published genome sequences for ferns and
lycophytes to examine how genome fractionation
may be occurring. We find that pteridophyte genomes
may fractionate relatively rapidly following WGD, but
chromosome order and collinearity are preserved. In-
cluding pteridophytes, for the first time, in compara-
tive work on fractionation is a key step to better under-
standing genome evolution in land plants.

S.25 TOWARDS INTEGRATIVE TAXONOMY.
THEORY AND PRACTICE. SESSION 2

S.25.1 Demographic
systematics-species
circumscription through
reciprocal illumination
among multiple
demographic levels and
data sources

Richard M. Bateman¹

1 Royal Botanic Gardens Kew, Richmond, UK
(r.bateman@kew.org)

Traditional morphological taxonomy utilises mul-
tiple preserved collections that collectively con-
stitute a serendipitous sample of organisms that
have been immediately killed and often also dis-
membered, thereby reducing the number of mor-
phological characters available for subsequent
study. The comparative approach typically applied
to herbarium specimens prioritises qualitative de-
scription above quantitative analysis and cerebral
rather than algorithmic assignments of specimens
to taxa; it also over-emphasises the holotype – a
single point in space and time. The contrasting ‘de-
mographic’ approach to taxonomy, illustrated here
using studies of European orchids, employs a statis-
tically rigorous in situ sampling strategy, and yields
large volumes of fully quantified data of two or more
<figure><img src="image_73.png" /></figure>

kinds obtained from the same spectrum of individ-
ual organisms. Each sampled individual is subject-
ed to character-rich morphometric data collection,
describing every organ, and to equally detailed
population genetic analysis; additional data cat-
egories are optional. Each category of data then
undergoes multivariate ordination via an algorithm
that does not require prior taxonomic assignment
of individuals. This approach entails two contrasting
forms of reciprocal illumination – the essential ele-
ment in any truly scientific enterprise. (1) Organisms
are aggregated into their source populations, and
populations into infraspecific taxa and species, rel-
atively large distances among sets of populations
providing the basis of a genuine species circum-
scription process. (2) Confidence in, and the under-
lying nature of, the putative species boundaries are
then determined through congruence among pat-
terns of similarity in contrasting categories of data,
addressed in the context of information gathered on
extrinsic properties such as symbiotic relationships,
habitat preference and putative geographic distri-
bution. Although the demographic approach con-
sumes considerably more time and resources than
traditional taxonomy, it rigorously tests initial species
hypotheses and provides far deeper understanding
of the resulting species – perhaps even sufficient to
predict their behaviour in the face of environmental
challenges such as climate change.

S.25.2 Integrating different
sources of data to
disentangle the taxonomy of
Nothoscordum (Allioideae,
Amaryllidaceae)

Agostina B. Sassone¹,², Frank R. Blattner¹

1 Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, Germany. 2 Facultad de Ciencias Agrarias, Universidad Nacional de Mar del Plata, Balcarce, Argentina

Nothoscordum (tribe Leucocoryneae) is a New
World genus distributed mainly in South America.
The huge number of species (ca. 60 new species
described in the last three decades out of a total
of 89 accepted species at POWO), and the difficulty
or impossibility of contrasting the description with
types, illustrations, and keys to species has created
a taxonomic confusion. This problematic scenario
together with the complexity of finding diagnostic
characters and the presence of reticulate patterns

in the evolution of the genus, has made the identi-
fication of the species a real challenge. The aim of
our research is to integrate different disciplines to
define taxa within *Nothoscordum* as part of the main
goal of reconstructing the evolutionary history of the
tribe Leucocoryneae. We have gathered 130 spec-
imens and inferred their phylogeny based on the
complete chloroplast genome and genome-wide
GBS loci, and collected where possible cytogenet-
ic data. Furthermore, we have statistically analyzed
morphological data from included specimens in
molecular analyses as well as from type specimens
(matrix size: 32 characters x 160 specimens). As a re-
sult, the gathered information agrees at some tax-
onomic levels (e.g., sections within *Nothoscordum*)
but only partially in other cases (e.g., on the species
level). Traditional morphological characters used to
distinguish species are in most cases not enough to
discern them, and it is important to consider molec-
ular data, phenology, and ecological traits as well.
Karyotypes are also helping to discriminate some
monophyletic groups. In summary, we dive into the
challenges of linking the different datasets, and the
new questions that have emerged.

S.25.3 Are all these
carnations supported?
Insights from integrative
taxonomy of the Dianthus
virgineus complex
(Caryophyllaceae)

Jacopo Franzoni¹, Gianluigi Bacchetta²,
Fabio Conti³, Giannantonio Domina⁴,
Simone Fior⁵, Luigi Minuto⁶, Lorenzo
Peruzzi¹

1 University of Pisa, Pisa, Italy. 2 University of Cagliari, Cagliari, Italy. 3 University of Camerino, Camerino, Italy. 4 University of Palermo, Palermo, Italy. 5 ETH Zürich, Zürich, Switzerland. 6 University of Genova, Genova, Italy

Species are hypotheses about how biological diver-
sity is structured in nature, and robust hypotheses
are typically supported by multiple lines of evidence.
However, traditionally botanists have been prone to
circumscribe species relying just on morphological
observations. For instance, the *Dianthus virgineus*
complex includes 21 wild putative species/subspe-
cies in the central Mediterranean recognized ac-
cording to qualitative morphology, but their bound-
<figure><img src="image_74.png" /></figure>

aries await to be explored with other approaches. Thus, we are conducting an integrative taxonomy project to test the current taxonomy of the complex. For this purpose, we collected morphometric, cytogenetic, and genomic (ddRAD-seq) data from over 100 populations belonging to all the 21 taxa. The global structure of the morphometric dataset, built using continuous and categorical variables, suggest the presence of just two main groups. Populations distributed from southern France to peninsular Italy show shorter calyx teeth, epicalyx scales and mucros with respect to populations from Sicily and Corso-Sardinian system (including Tuscan Archipelago). These two groups show sub-clusters, only in some cases mirroring currently accepted taxa. These plants are all diploid with constant chromosome number (2n = 2x = 30), albeit relative genome size is slightly higher in populations from Sicily and from Corso-Sardinian system. Genotyping thousands of SNPs revealed a genetic structure that parallels geography rather than taxonomy. Studied populations from the central Mediterranean belong to a unique genetic lineage, structured in two major clines. A first cline extends from southern France to the southern part of the Italian Peninsula, and the other from the Italian Peninsula to the Tuscan Archipelago, Corsica, and Sardinia. Sicilian and Sardinian populations are linked through those originating from Tunisia. All these evidences point to a number of groups lower than currently recognized taxa. In-depth morphometric classification models and multispecies coalescence model-based approaches are currently ongoing to test current and alternative taxonomical settings.

### S.25.4 Tackling taxonomy of the mega-diverse genus Begonia

Mark Hughes<fnref n="1" />, Wisnu H. Ardi²,³, Gosse S. Bootsma<fnref n="1" />,⁴, Dipankar Borah⁵, Janet Gagul⁶, Deden Girmansyah², Toby Mills<fnref n="1" />, Peter W. Moonlight⁷, Adolfo Jara-Muñoz⁸, Martin Pullan<fnref n="1" />, Sangeeta Rajbhandary⁹, Rosario R. Rubite¹⁰, Madhavi Sreenath<fnref n="1" />, Daniel C. Thomas¹¹, Mark C. Tebbitt¹², Hannah P. Wilson<fnref n="1" />, Keqiao Zhong<fnref n="1" />

Queen's University, Belfast, Northern Ireland, UK. 5 Department of Botany, Goalpara College, India. 6 Biological Sciences, University of Papua New Guinea, Papua New Guinea. 7 Department of Botany, Trinity College Dublin, Ireland. 8 Universidad Nacional de Colombia, Colombia. 9 Central Department of Botany, Tribhuvan University, Nepal. 10 Department of Biology, College of Arts and Sciences, University of the Philippines Manila, Philippines. 11 Singapore Botanic Gardens, Singapore. 12 Department of Biology, Geology and Environmental Sciences, California University of Pennsylvania, USA

Large genera are at the forefront of taxonomic endeavour, as they often need a considerable amount of work and represent unique challenges due to the number of species involved, such as how to delimit bite-size groups for revision and how to best work collaboratively. Here we demonstrate an approach to tackling the taxonomy of the mega-diverse genus Begonia (2132 accepted species), using a relational database system (PADME) developed at the Royal Botanic Garden Edinburgh to manage nomenclatural and specimen linked data. We built on published hard copy checklists to make an electronic checklist of current nomenclature and taxonomy. We then added images of protologues and specimens, and included specimen-associated information in the database, with currently 60,327 specimens. What emerged was a specimen-driven multi-user dataset, permitting checklist production for any geographic area annotated with current nomenclature plus type and other herbarium specimens, facilitating a new wave of taxonomic work on the genus. Specimen annotations such as phenology and georeferenced localities have supported emergent global scale macroecological studies on the genus. More recently, we have used DNA data to craft a new stable subgeneric classification for Begonia in order to facilitate revisionary taxonomy and identification, and also added species descriptions from protologues, revisions and floras in a World Flora Online compliant format. We now have a 50% complete draft WFO account for the world's fastest growing genus. Our approach shows the value of the investment of time in baseline taxonomy, and the facilitatory effects of regional checklists and digitised specimens.

<footnote n="1">1 Royal Botanic Garden Edinburgh, Scotland, UK. 2 Research Center for Biosystematics and Evolution, BRIN, Cibinong, Indonesia. 3 University of Florida, USA. 4 School of Natural and Built Environment,</footnote>
<figure><img src="image_75.png" /></figure>

**S.25.5 A heuristic approach to species delimitation in the charismatic giant waterlily genus Victoria**

Lucy T. Smith¹ Carlos Magdalena¹ Natalia A. S. Przelomska¹,²,⁵ Oscar A. Pérez-Escobar¹* Darío G. Melgar-Gómez³ Stephan Beck⁴ Raquel Negrão¹ Sahr Mian¹ Ilia J. Leitch¹ Steven Dodsworth⁵ Olivier Maurin¹ Gaston Ribero-Guardia⁶ César D. Salazar⁷ Gloria Gutierrez-Sibauty³ Alexandre Antonelli¹,⁸,⁹ Alexandre K. Monro¹*

¹Royal Botanic Gardens, Kew, Richmond, UK. ²National Museum of Natural History, Smithsonian Institution, Washington, DC, United States. ³Herbario German Coimbra Sanz, Jardín Botánico Municipal de Santa Cruz de la Sierra, Santa Cruz de la Sierra, Bolivia. ⁴Herbario Nacional de Bolivia, Universidad Mayor de San Andrés, La Paz, Bolivia. ⁵School of Biological Sciences, University of Portsmouth, Portsmouth, UK. ⁶La Rinconada Ecoparque, Santa Cruz, Urbari, Bolivia. ⁷Calle 11 Norte #24, Urbari, Bolivia. ⁸Gothenburg Global Biodiversity Centre, Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden. ⁹Department of Plant Sciences, University of Oxford, Oxford, UK.

Reliably documenting plant diversity is necessary to protect and sustainably benefit from it. At the heart of this documentation lie species concepts and the practical methods used to delimit taxa. Here, we apply a total-evidence, iterative methodology to delimit and document species in the South American genus Victoria (Nymphaeaceae). The systematics of Victoria has thus far been poorly characterized due to difficulty in attributing species identities to biological collections. This research gap stems from an absence of type material and biological collections, also the confused diagnosis of *V. cruziana*. With the goal of improving systematic knowledge of the genus, we compiled information from historical records, horticulture and geography and assembled a morphological dataset using citizen science and specimens from herbaria and living collections. Finally, we generated genomic data from a subset of these specimens. Morphological and geographical observations suggest four putative species, three of which are supported by nuclear population genomic and plastid phylogenomic inferences. We propose

these three confirmed entities as robust species, where two correspond to the currently recognized *V. amazonica* and *V. cruziana*, the third being new to science, which we describe, diagnose and name here as *V. boliviana* Magdalena and L. T. Sm. Importantly, we identify new morphological and molecular characters which serve to distinguish the species and underpin their delimitations. Our study demonstrates how combining different types of character data into a heuristic, total-evidence approach can enhance the reliability with which biological diversity of morphologically challenging groups can be identified, documented, and further studied.

**S.25.6 Reconciling the taxonomy, morphology, and evolutionary history of the coca crops (Erythroxylum spp.)**

Dawson M. White¹

¹Harvard University Herbaria, Cambridge, USA

Coca represents one of the most culturally significant and oldest crops in the Americas. As the natural source of cocaine, coca is also internationally proscribed under various applications of taxonomy and/or biochemical data. However, recent phylogenetic and phylogeographic studies of the coca crops and closest wild relatives have revealed a complex evolutionary blueprint substantiating taxonomic revisions. The widespread wild species Erythroxylum gracilipes is a paraphyletic taxon containing two or three clades of coca taxa (E. coca and E. novogranatense; each with two varieties) plus the wild species E. cataractarum. Additionally, genetic, and morphological studies indicate intraspecific hybrids are being cultivated for the illicit cocaine market. This presentation provides an overview of the recent genetic and morphological research on the coca clade and discuss various taxonomic proposals that could be more informative of this evolutionary history.
# S.26 AFRICAN TAXONOMY: A COLLABORATIVE EFFORT TOWARDS BIODIVERSITY CONSERVATION. SESSION 1

## S.26.1 Taxonomic revision of the genus Eulophia R. Br. (Orchidaceae) in Ghana

Benjamin Darko Williams¹, Matthew Kweku Essilfie¹, Alex Asase²

1 Department of Plant and Environmental Biology, University of Ghana, Ghana. 2 Centre for Scientific Research into Plant Medicine, Ghana

Eulophia R. Br. is one of the prominent ground orchids in West Africa and Central Africa, however, there is no complete taxonomic revision of the genus Eulophia in Ghana although a revision has been carried out in Nigeria, Cameroon, Equatorial Guinea, Gabon, and the Republic of the Congo. The goal of this study is to determine the range of morphological variations within the genus in order to clarify the delimitation of the taxa in Ghana; evaluate aspects of the ecology and distribution of the genus in Ghana. Field trips to collection sites as cited by the major herbaria in Ghana yielded no live plants although the visits were done following the cited collection dates. Urbanization and land use change is quickly destroying the habitats of the members of this genus. Morphological studies carried out on preserved specimens suggested eight species of Eulophia in Ghana, with the most common members found in grasslands. Members of the genus have a cosmopolitan distribution across the country, with the least distribution around the western part. The genus produces flowers and fruits between March to May, with the exception of E. cristata (Afzel. ex Sw.) Steud. producing flowers in January also.

## S.26.2 A case for the nameless – Accelerating plant taxonomy as a tool for conservation, using Indigofera as a case study

Brian du Preez¹,², Brian D. Schrire³, Leanne L. Dreyer², Charles H. Stirton¹, A. Muthama Muasya¹

1 Bolus Herbarium, Department of Biological Sciences, University of Cape Town, Rondebosch, South Africa. 2 Department of Botany and Zoology, Stellenbosch University, Matieland, South Africa. 3 Honorary Research Associate, Accelerated Taxonomy Department, Royal Botanic Gardens, Kew, Richmond, Surrey, UK.

The saying that we cannot conserve what we do not know presents one of the greatest dilemmas in the face of a probable sixth mass extinction. While many large and charismatic organisms enjoy substantial conservation efforts in terms of funding and public sentiment, thousands of smaller and lesser-known species face the prospect of extinction out of the public eye. We are for fortunate to have one of the best plant red data lists globally that helps to monitor our more than 20 000 plant species in South Africa. Yet, despite a rich history of plant taxonomy in SA dating back to the 1700's, many of our plant species remain undescribed and poorly known. *Indigofera* is an example of a genus that is poorly known and harbors numerous undescribed species. The Greater Cape Floristic Region (GCFR) is home to a diverse assortment of *Indigofera* species, but the last taxonomic account of these species was done in 1862. I aimed, in my PhD study, to taxonomically revise the genus *Indigofera* in the GCFR. Following an intensive regime of field sampling and herbarium analyses, I found 55 undescribed *Indigofera* species in the GCFR, meaning that these 55 species have never received any conservation attention, with some of these species being severely threatened. However, through this study, we now understand and recognize the diversity of *Indigofera* in the GCFR and can inform conservation authorities and landowners of the presence of these
previously unknown species. The extensive fieldwork conducted during this study has contributed invaluable information that can be used to help conserve these species by identifying past, present and future threats. This study demonstrates the value of taxonomic studies when combined with extensive field sampling, in firstly helping to understand and quantify species diversity, and through that contribute to the subsequent conservation of biodiversity.

## S.26.3 Rediscovery of Nymphaea thermarum Eb. Fisch. in Rwanda

Thomas Abeli¹,², Sarah M. Müller³, Siegmar Seidel³

1 Department of Science, Roma Tre University, Rome, Italy. 2 IUCN SSC Conservation Translocation Specialist Group, Calgary, Canada. 3 Rwanda Centre and Office for Africa Cooperation, University of Koblenz, Koblenz, Germany

Nymphaea thermarum is a small waterlily endemic to Rwanda that is being assessed as extinct in the wild since 2010. The species has been rediscovered in July 2023 not far from its locus classicus. We report on the rediscovery of *N. thermarum*, identify the current and potential threats for the wild populations, namely mining and overharvesting by collectors, respectively and provide a list of urgent conservation measures and research required to save the species from "re-extinction". The species occupies small muddy ditches fed by hot springs water use to water Avocado plantations and fish pools. The population counts hundreds of individuals including adult reproducing plants and seedlings. In the short term, important conservation actions should include land protection, negotiation to ensure that enough water is reaching the habitat of *N. thermarum* and the reassessment of the species against the IUCN Categories and Criteria to update its status. In a new formal IUCN assessment, the species would quality as Critically Endangered. In the medium-term the creation of a nature reserve, the restoration of the areas already affected by mining and the reintroduction of *N. thermarum* to its original site, would place the species into a better position for its long-term in situ conservation.

## S.26.4 Potential impacts of climate change on geographic distribution and conservation of the genus Talbotiella

Alex Asase¹, Daniel Jiménez-García², Andrew Townsend Peterson³

1 Centre for Plant Medicine Research, P. O. Box 73, Mampong-Akuapem, Ghana. 2 Centro de Agroecología y Ambiente, Instituto de Ciencias, Benérita Universidad Autónoma de Puebla, Puebla, Puebla, Mexico. 3 Biodiversity Institute, University of Kansas, Lawrence, Kansas, USA

Although climate change is a leading cause of species extinction, the effects of climate change on geographic distributions and conservation status of African plants have not seen detailed evaluation. We employed ecological niche modelling approaches to investigate the potential effects of climate change on geographic distributions of the threatened West-Central African genus *Talbotiella*. The results of the study showed habitat suitability was lower in the northern parts of its range in West Africa and at its southern extremes in West-Central Africa. Potentially suitable areas where new populations or species of the genus could be discovered in West Africa was between Liberia and southwestern Ghana. Model transfers to future conditions showed range shifts and contractions in geographic distributions. Conservation of species of the genus should also include threats by factors such as degradation, agriculture and development of industrial infrastructure. Our study shows how niche modelling approaches could be used to enhance the conservation and discovery of African biodiversity.
<figure><img src="image_76.png" /></figure>

S.26.5 Digitization and
Enrichment of U.S.
Herbarium Data from
Tropical Africa to Enable
Urgent Quantitative
Conservation Assessments

Patricia Barberá¹, Alex Asase²,³, Israel
T. Borokini⁴, Alison Colwell⁵, Charles C.
Davis⁶, Nico M. Franz⁷, Peter Fritsch⁸,⁹,
Edward Gilbert⁷,¹⁰, Bonnie L. Isaac¹¹,
Robert Johnson¹², Beth A. Kaplin¹³,¹⁴,
Rebecca Y. Kartzinel¹⁵, Maria Lucia
Kawasaki¹⁶, Jonathan Kennedy⁶,
Jennifer Kluse¹⁷, Elena M. Kramer⁶, Laura
Lagomarsino¹⁷, Tatyana Livshultz¹⁸,¹⁹,
Porter P. Lowry¹, Michelle McMahon²⁰,
Brent D. Mishler²¹, Tiwonge I. Mzumara²²,
Mare Nazaire²³, Kevin C. Nixon²⁴, Nestor
Engone Obiang²⁵, Sylvia Orli²⁶, ²⁷, Katelin
Pearson⁷,¹⁰, A. Townsend Peterson²⁸,
Daniel Potter⁵, Mitchell J. Power²⁹, Tiana
F. Rehman⁸,⁹, Heidi Schmidt¹, D. Rabern
Simmons³⁰, Michaela Schmull⁶, Eric
Schuetpelz²⁶,²⁷, Chelsea R. Smith¹⁶, Neil
Snow³¹, Patrick W. Sweeney³², Nicole
Tarnowsky³³, Jordan K. Teisher¹, George
D. Weiblen³⁴, Timothy J.S. Whitfeld³⁴,
John Wieczorek³⁵, Paula Zermoglio³⁶

1 Missouri Botanical Garden, St. Louis, Missouri,
USA. 2 Centre for Plant Medicine Research, Mam-
pong-Akuapem, Ghana. 3 University of Ghana,
Accra, Ghana. 4 Montana State University, Boz-
eman, Montana, USA. 5 University of California,
Davis, Davis, California, USA. 6 Harvard Univer-
sity, Cambridge, Massachusetts, USA. 7 Arizo-
na State University, Tempe, Arizona, USA. 8 Bo-
tanical Research Institute of Texas, Fort Worth,
Texas, USA. 9 Fort Worth Botanic Garden, Fort
Worth, Texas, USA 10. Integrated Digitized Bio-
collections, Gainesville, Florida, USA. 11 Carnegie
Museum of Natural History, Pittsburgh, Pennsyl-
vania, USA. 12 Bringham and Young University,
Provo, Utah, USA. 13 University of Rwanda, Kigali,
Rwanda. 14 University of Massachusetts Boston,
Boston, Massachusetts, USA. 15 Brown University,
Providence, Rhode Island, USA. 16 Field Museum
of Natural History, Chicago, Illinois, USA. 17 Lou-
isiana State University, Baton Rouge, Louisiana,

USA. 18 Academy of Natural Sciences of Drexel University, Philadelphia, Pennsylvania, USA. 19 Drexel University, Philadelphia, Pennsylvania, USA. 20 University of Arizona, Tucson, Arizona, USA. 21 University of California Berkeley, Berkeley, California, USA. 22 Malawi University of Science and Technology, Mikolongwe, Malawi. 23 California Botanic Garden, Claremont, California, USA. 24 Cornell University, Ithaca, New York, USA. 25 L'Herbier National du Gabon, Libreville, Gabon. 26 National Museum of Natural History, Washington D.C., USA. 27 Smithsonian, US National Herbarium, Washington, D.C., USA. 28 University of Kansas, Lawrence, Kansas, USA. 29 University of Utah, Salt Lake City, Utah, USA. 30 Purdue University, West Lafayette, Indiana, USA. 31 Pittsburg State University, Pittsburg, Kansas, USA. 32 Yale Peabody Museum, Yale University, New Haven, Connecticut, USA. 33 New York Botanical Garden, Bronx, New York, US. 34 Bell Museum, University of Minnesota, Saint Paul, Minnesota, USA. 35 Rauthiflor LLC, Bariloche, Argentina. 36 Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural (IRNAD) Sede Andina, Universidad Nacional de Río Negro, San Carlos de Bariloche, Río Negro, Argentina

Herbarium specimens represent a rich source of
data on plant diversity. These rich information
resources, however, too often remain in analog
format only, and have not been digitized and "en-
abled" in the service of science. This project aims
to digitize, enrich, and share openly the rich data
resources held in 21 U.S. herbaria that correspond
to plants of tropical Africa, which will total more
than 1.1 million herbarium specimens. Imaging
and data capture is being carried out at each
of the herbaria, and data are then aggregated
for efficient georeferencing. For most records,
georeferencing is being performed automat-
ically, and the remainder will be georeferenced
manually by plant scientists in Ghana, Rwanda,
Malawi, and Gabon. Finally, project data will be
subjected to detailed quality-control assessment
and served openly to the scientific community
via a dedicated "African Plants" portal on Sym-
biota (https://serv.biokic.asu.edu/africa/plantae/
index.php), as well as integration into biodiversity
data portals such as iDigBio and GBIF. The proj-
ect has thus created a broad, international, in-
tercontinental network of scientists and students
interested in and experienced with management
and analysis of data about African plant distri-
butions. These rich data resources will be used
to understand the conservation status of African
plant species in much greater detail than has
been possible to date.
<figure><img src="image_77.png" /></figure>

**S.26.6 Enhancing taxonomy skills in Africa: joining efforts in training and international collaborations**

Ana Rita G. Simões¹

¹ Royal Botanic Gardens, Kew, UK.

Plant taxonomy is a diverse and increasingly integrative discipline. With the expansion of digitally available collections, innovative molecular methodologies and geospatial analyses, there is an outstanding opportunity for this field to grow, and

for the African continent, in particular, to accelerate the documentation of its plant diversity as never before. However, insufficient specialised human resources, unequal access to resources, and deficient infra-structure could weaken this momentum. Enhancing taxonomy training in Africa is key to filling in the specialists' gap and overcome biases and inequalities in access to these skills. This presentation offers an overview of current challenges and opportunities for plant taxonomy training, particularly in Africa, with suggestions on how to strategically design plant taxonomy training initiatives that efficiently tackle regional needs, fostered by international collaboration.

**S.27 A CONTINENTAL SCALE CONSORTIUM APPROACH TO BUILDING GENOMICS CAPACITY AND RESOURCES: GENOMICS FOR AUSTRALIAN PLANTS. SESSION 2**

**S.27.1 Resolving taxonomy challenges in species complexes using conservation genomics**

Margaret Byrne¹, Rachel Binks¹, Kelly Shepherd¹, Laura Simmons², Katherina Nargar³,⁴, Michael Bayly⁵, Andre Messina²

¹ Department of Biodiversity, Conservation and Attractions, Perth, Australia. ² Royal Botanic Gardens, Melbourne, Australia. ³ James Cook University, Cairns, Australia. ⁴ CSIRO, Cairns, Australia. ⁵ University of Melbourne, Melbourne, Australia

Species complexes are often present in floras with high diversity driven by complex evolutionary history and associated high speciation and low extinction rates. Whilst most species are readily identified and described, there are many species complexes where taxa are challenging to resolve though morphological analysis alone. Genomic approaches can assist in this challenge through identification of relationships at the species-population interface providing an evolutionary basis for identifying taxon boundaries, including where ongoing hybridisation con-

fuses morphological relationships. The Genomics for Australian Plants initiative is a national collaborative program that is developing genomic resources to enhance understanding of the evolution and conservation of the diverse Australian flora. One of its three components is application of a conservation genomics approach to taxonomic resolution of challenging species complexes in the Australian flora. This integrated approach brings taxonomists and geneticists together, applying an evolutionary biology lens to identification of taxonomic entities. The focus has been on resolving taxa in complexes where there are likely taxa of conservation concern so they can be defined and considered in conservation listing, facilitating implementation of management actions. The initiative has supported projects covering 11 species complexes and clarified relationships amongst entities, using ddRAD genomic data in combination with morphological assessment. The relative outcomes of ddRAD and the angiosperm 365 bait kit were also tested for four species complexes. These analyses have led to the identification of species of conservation concern, as well as clarification of situations where morphological variation is not reflective of taxonomic separation, or where hybridisation is a complicating factor obscuring morphologi-
cal relationships. The outcomes demonstrate the benefits of an integrated approach using genomic and morphological methods to facilitate taxonomic resolution of species complexes. This approach may be readily implemented in other highly diverse floras where taxonomic identification of conservation entities is critical to effective conservation action.

**S.27.2 Using genomic tools to explore diversity in Southwest Australian plants of conservation concern**

Benjamin M. Anderson¹, Rachel M. Binks¹,
Ryonen Butcher¹, Margaret Byrne¹,
Andrew D. Crawford¹, Terry D. Macfarlane¹,
Barbara L. Rye¹, Kelly A. Shepherd¹

1 Department of Biodiversity, Conservation and At-
tractions, Western Australia, Perth, Australia

The Southwest Australian Floristic Region contains high angiosperm diversity (>7500 species) often occuring in managed landscapes with varying levels of anthropogenic disturbance, which creates a taxonomic and conservation challenge to understand, classify and protect these organisms. Evolutionary patterns in the flora of this historically stable region are diverse, with widespread, genetically-connected lineages contrasting those with restricted or discontinuous ranges and complex genetic structure. While much of the flora has been described, some groups with morphological complexity or subtlety (and putative evolutionary complexity) have frustrated taxonomists and prompted the use of genomic techniques to help unravel that complexity. As part of the Genomics for Australian Plants initiative, we applied reduced representation genomic approaches (ddRAD, sequence capture) to species complexes suspected to contain cryptic taxa of conservation concern. Our goal was to resolve the taxonomy of these complexes. We present some of our results, along with reflections on the effectiveness and appropriateness of the molecular approaches for our goal. Our findings include unexpected diversity leading to the recognition of more species, as well as the contrasting pattern of unanticipated genetic connectivity leading to fewer species. We also encountered challenges that reflect the complex biology of these

systems and highlight the need for fundamental
knowledge of e.g. breeding system, ploidy and
dispersal patterns when approaching this flora
and interpreting genetic data.

S.27.3 A species-level
phylogeny of eastern
Australian Phebalium Vent.
sect. Phebalium Duretto
& Heslewood (Rutaceae;
Zanthoxyloideae)

Sangay Dema¹, Rose L. Andrew¹, Ian R.H. Telford¹, Jeremy J. Bruhl¹

1 N.C.W. Beadle Herbarium, University of New England, Armidale, Australia

Phebalium Vent. sect. Phebalium Duretto & Heslewood is an Australian endemic monophyletic group of species with 14 species distributed in south-western Australia and 21 in eastern Australia. Most species of Phebalium have strong horticultural potential, while many are narrowly endemic and of high conservation value. Underpinned by morphological, phytochemical and molecular data, we recognised 15 new species, and we are reinstating four species and raising eight subspecies to the rank of species. From the few previous studies in Phebalium, most species-level relationships remained untested or unresolved. Our SNP-based phylogenetic analysis of all eastern Australian Phebalium taxa, including the newly delimited species, was carried out using maximum likelihood with IQ-TREE2 and maximum parsimony with PAUP. We also inferred phylogenetic relationships under a coalescent model using SVDquartets. The phylogenetic relationships inferred under all models were concordant. Our analyses recovered three major clades within eastern Australian Phebalium corresponding to three species complexes involving P. squamosum, P. glandulosum and P. nottii. The monophyly and inter-specific relationships of most of the eastern Australian species of Phebalium were resolved and will be discussed.
## S.27.4 Phylogenomic analysis of generic limits underpins a systematic study of Chrysocephalum (Gnaphalieae, Asteraceae)

Shelley A. Rowntree¹,², Alexander N. Schmidt-Lebuhn², Jeremy J. Bruhl¹, Ian R. H. Telford¹, Rose L. Andrew¹

¹Botany and N.C.W. Beadle Herbarium, University of New England, Armidale, Australia. ²Centre for Australian National Biodiversity Research, CSIRO, Canberra, Australia

Chrysocephalum Walp. is a medium-sized genus in the Waitzia clade of the Australian Gnaphalieae (Asteraceae), comprising nine currently recognised species and two phrase-named species. In a recent revision of the *C. apiculatum* and *C. semipapposum* complexes (Wilson 2016), 34 subspecies were added based on morphological

characters, with a high level of complexity making distinction difficult among them. Detailed relationships within the clades of the Gnaphalieae remain largely unresolved, and generic concepts have often been based on a small number of morphological characters traditionally considered important. We have inferred a molecular phylogeny of selected Australian native Gnaphalieae (Asteraceae) to test the monophyly of the *Chrysocephalum* using target capture sequences and a bioinformatics pipeline co-developed through the Genome of Australia Plants Consortium. A group of three species form the "core" *Chrysocephalum* clade, *C. apiculatum* (type species), *C. semipapposum* and *C. vitellinum*. Arid zone species form separate clades. We are also resolving species-level relationships with molecular and morphological analyses. This study will resolve long-standing taxonomic issues and, as the study group includes several rare and threatened taxa whose status will be clarified, will also support biodiversity conservation.

## S.28 EVOLUTIONARY ECOLOGY OF PLANTS. SESSION 2

### S.28.1 Rapid evolution of ecological strategies in Arabidopsis thaliana

Maria Stefania Przybylska¹,²,³, Cyrille Violle¹, Denis Vile², JF Scheepens³, Léo Delalandre¹, Lily Bennett¹, Eric Garnier¹, François Vasseur¹

¹CEFE, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France. ²LEPSE, Univ Montpellier, INRAE, Institut Agro Montpellier, Montpellier, France. ³Goethe University Frankfurt, Frankfurt am Main, Germany

The study of ecological strategies, i.e., sets of covarying traits that match with environmental conditions in a potential adaptive way, helps to address the role of the phenotype as a whole, rather than individual traits, in adaptation. Because, in the field, covariation between environmental conditions makes it difficult to test for the concrete factors driving ecological strategies, experimental approaches can be valuable. Using experimen-

tal evolution, we tested for the evolution of both mean phenotypes and their variance in response to contrasting levels of stress (resource availability) and disturbance (herbivory) in *Arabidopsis thaliana*. By tracking the phenotypic space formed by whole-plant and leaf traits, we found that, after only three generations, *A. thaliana* populations diverged both in terms of phenotypic variation and trait syndromes in response to contrasting resource and herbivory treatments. The most divergent responses were found to evolve under low and high resources without herbivory: a strategy of fast-growth for stress escape and a strategy of slow-growth for competitive ability, respectively. Furthermore, these strategies have been shown to be adaptive and possibly density-dependent. Our results highlight the rapid evolution of plant strategies in response to stress and disturbance and the key importance of population size in ecological analyses.