bluuebunny/crossref_metadata_2025 huggingface dataset:
Taxonomic revision of Sargassum sect. Acanthocarpicae (Fucales, Phaeophyceae)
Authors: Mattio Lydiane , Payri Claude E. , Verlaque Marc , de Reviers Bruno
Published: February 2019

Sargassum is one of the morphologically most complex phaeophyceaen genera, and is divided into subgenera, sections, subsections, series and species groups based on highly polymorphic characters. Recent DNA analyses have highlighted incongruities in the traditional classification of the genus and especially within Sargassum subg. Sargassum sect. Acanthocarpicae. Our goal was to re–assess the relationships among taxa currently attributed to this section in the Pacific basin. We undertook the taxonomic study in two main steps: (1) the morphological examination of large collections from inter–tropical Pacific islands and type specimens from worldwide localities; and (2) DNA analyses using a set of three markers (ITS–2, partial rbcLS–operon, cox3). Morphological and DNA analyses confirmed that S. sect. Acanthocarpicae is based on unsuitable morphological characters and is not monophyletic. On the basis of this study, we propose (1) abandoning subsections within S. sect. Acanthocarpicae; (2) synonymization of S. sect. Acanthocarpicae and sect. Malacocarpicae with sect. Sargassum; and (3) the elevation of S. ser. Ilicifoliae and ser. Binderianae to sectional rank as well as their re–description according to new sets of morphological characters.
Typification and nomenclature of Podocarpus angustifolius Griseb. and Podocarpus aristulatus Parl. (Podocarpaceae)
Authors: Mill Robert R. , Stark Schilling Darian M.
Published: February 2019

The nomenclature of Podocarpus angustifolius Griseb. and P. aristulatus Parl., names applied to two taxonomically distinct Cuban species of Podocarpus sect. Pumilis (Podocarpaceae), is discussed. Both names are based on material collected by Charles Wright. The complexities of typifying names based on this collector's material are summarised, emphasising that material bearing the same “Wright number” cannot always be considered duplicate type material, Wright's numbers being distribution not collection numbers. In this particular case, the dioecy of Podocarpus further complicates matters because the original material of P. angustifolius at GOET, formerly regarded as a holotype, consists of two shoots of different sexes, plus detached seeds that are more mature than those on the mounted female shoot. We demonstrate that these three elements all have different provenances and must be regarded as syntypes. The name Podocarpus angustifolius Griseb. is lectotypified by the detached seeds at GOET, and a supporting epitype designated to fix the application of the name. Podocarpus aristulatus Parl. was based partly on the type of the earlier name P. angustifolius Griseb. of which Parlatore was unaware. However, Parlatore did not see all syntypes present in Grisebach's original material of that name; moreover his name P. aristulatus has been consistently applied to a taxonomically different entity from eastern Cuba, rather than western Cuba where the lectotype of Podocarpus angustifolius was collected. In order to maintain nomenclatural stability it is recommended that P. aristulatus be either lectotypified or conserved with a new conserved type. The latter option is favoured and a separate proposal to that effect is being published simultaneously.
Monophyly and paraphyly: A discourse without end?
Authors: Podani János
Published: February 2019

The ongoing discourse on monophyly versus paraphyly shows apparent lack of mutual understanding among schools of biological taxonomy. The principal reason behind the frozen disagreement is that these terms were redefined repeatedly. Although terminological discrepancy has long been recognized, relatively few attempts have been made to clarify this. As a consequence, contemporary taxonomy still uses three different definitions of monophyly, and therefore paraphyly. Resolution is possible provided that the terms (a) monophyly and paraphyly are used for diachronous classifications and phylogenetic trees; (b) monoclady and paraclady for synchronous classifications and cladograms of contemporaneous organisms; and (c) monothety and non‐monothety for groups in classifications derived by the pattern cladistic approach.
Origin and phylogenetic relationships of the Old World Gesneriaceae with actinomorphic flowers inferred from ITS and trnL-trnF sequences
Authors: Wang Yin-Zheng , Liang Rong-Hua , Wang Bo-Han , Li Jia-Mei , Qiu Zhi-Jing , Li Zhen-Yu , Weber Anton
Published: February 2019

The phylogenetic placement of the Old World Gesneriaceae genera Ramonda, Conandron, Bournea, Thamnocharis, and Tengia, all characterized by actinomorphic flowers, has been the subject of much debate. Actinomorphy in Gesneriaceae is rare, with most species exhibiting zygomorphic flowers. The actinomorphic genera have historically been considered “primitive” and lumped in the tribe Ramondeae separate from the remaining Old World Gesneriaceae. In this study, we used nuclear (ITS) and plastid (trnL‐F) DNA for molecular phylogenetic analysis of these five genera along with representative species across the Cyrtandroideae. Our results show that the actinomorphic genera are scattered over several otherwise zygomorphic clades within Cyrtandroideae, and along with previous data, indicate that Ramondeae is an unnatural group. Floral actinomorphy has evolved convergently in different alliances of Old World Gesneriaceae. Ramonda is sister to Haberlea, Bournea is apparently paraphyletic, Conandron seems rather isolated, and Tengia is close to Petrocodon and sister to a group of Chirita sect. Gibbosaccus together with Calcareoboea. We hypothesize that the evolution from zygomorphy to actinomorphy with novel combinations of characters is possibly due to shifts in pollination strategies, such as a switch from nectar‐ to pollen‐rewards.
Contribution of mitochondrialcox1intron sequences to the phylogenetics of tribe Orchideae (Orchidaceae): Do the distribution and sequence of this intron in orchids also tell us something about its evolution?
Authors: Inda Luis A. , Pimentel Manuel , Chase Mark W.
Published: February 2019

In this paper, we use the mitochondrial regioncox1to assess the usefulness of this marker in addressing evolutionary relationships within the tribe Orchideae. Despite the low overall variation uncovered in this region, one good phylogenetic marker was identified. A large group I intron was shared across subtribe Orchidinae and some species of Habenariinae sensu Dressler. The clades identified in thecox1tree were weakly supported, but consistent with previous studies based on nuclear ribosomal spacers (nrITS). Moreover, the phylogenetic analysis of the combinedcox1/ITS data matrix allowed us to highly improve the resolution of the ITS‐only analysis and confirm several previously controversial relationships. A second purpose of this study was to analyse the evolution of the group Icox1intron in Orchideae. This intron has a patchy distribution in angiosperms that has been claimed to be mostly due to horizontal transfer events. Our results suggest that, despite the differences observed in the co‐conversion tracts in the tribe, vertical transfer is more consistent with the observed phylogenetic trees.
Phylogeny of Solanum series Piurana and related species in Solanum section Petota based on five conserved ortholog sequences
Authors: Ames Mercedes , Spooner David M.
Published: February 2019

Taxonomic complexity in wild potatoes (Solanum L. sect. Petota Dumort.) has led to widely conflicting treatments. Solanum ser. Piurana Hawkes is one of 21 series recognized in S. sect. Petota in the latest comprehensive taxonomic treatment by Hawkes in 1990. They are distributed from southern Colombia south through Ecuador to central Peru. The taxonomic limits of the series and validity of its constituent species were not resolved with previous studies. In the present study, a set of five conserved orthologous DNA markers (cos II) with 5342 bp of aligned length were used to infer the phylogeny of putative members of Solanum ser. Piurana and outgroups. The results agreed with a three‐clade topology shown by previous studies within S. sect. Petota. Solanum ser. Piurana is expanded to include some species formerly included in S. sers. Conicibaccata, Cuneoalata, Ingaefolia, Olmosiana, Simplicissima, Tuberosa and Yungasensa. This expanded group is supported morphologically by the presence of moniliform tubers and coriaceous leaves in most species.
Ontogenetic and phylogenetic diversification of the hooded staminode in Marantaceae
Authors: Pischtschan Elke , Ley Alexandra C. , Claßen-Bockhoff Regine
Published: February 2019

The flowers of Marantaceae are known for their unique pollination mechanism mediated by an explosive style movement. The mechanism is based on the highly modified elements of the inner androecial whorl, i.e., the single half‐fertile anther and the fleshy and hooded staminodes. We investigated 67 species across 24 genera to elucidate which parts of the hooded staminode are shared by all species, thus likely under strong selection pressure, and which are allowed to vary. We treated hooded staminodes as character syndromes and grouped them based on gross similarities. We identified characters underlying the similarity and investigated their diversity and developmental pathways. All hooded staminodes correspond in their general morphology, development and vascularisation, suggesting they are homologous. Variable proportions, differential growth and the formation of secondary structures result in a diversity of morphologies. The hooded staminodes can be grouped into ten distinct types. These morphological types are in accordance with the accepted clades of the family indicating their phylogenetic significance. The early diverging clades are characterised by stiff and elaborate staminode structures whereas in more distantly diverging clades simplified forms appear. We conclude that elaborate structures are not essential to maintain the pollination mechanism and thus have been reduced in the course of evolution.
Sectional rearrangement of arborescent clades of Croton (Euphorbiaceae) in South America: Evolution of arillate seeds and a new species, Croton domatifer
Authors: Riina Ricarda , van Ee Benjamin , Wiedenhoeft Alex C. , Cardozo Alfonso , Berry Paul E.
Published: February 2019

Most of the arborescent Croton species in the New World were treated by Webster as belonging either to C. sect. Cyclostigma Griseb. or C. sect. Luntia (Neck. ex Raf.) G.L. Webster. The circumscription of C. sect. Cyclostigma has been treated recently. In this paper we focus on C. sect. Luntia, which was subdivided by Webster into two subsections, C. subsect. Matourenses and subsect. Cuneati. Using chloroplast trnL‐F and nuclear ITS DNA sequence data, morphology and a broader sampling of additional Croton lineages, we found that the two subsections are not closely related and form distinct monophyletic groups. Substantial morphological differences support the molecular data. A taxonomic recircumscription of the two subsections, elevated to sectional level, is proposed. A key and taxonomic revision, with new synonyms, is provided for C. sect. Cuneati; together with the description of a new species from the coastal mountains of Venezuela, Croton domatifer. The new species is the only one in the genus known to possess leaf domatia. We infer that species in the Cuneati clade have lost the typical Croton caruncle, and some of them have evolved a different, specialized type of aril. We hypothesize that the arillate seeds are an adaptation to dispersal by fish in the Orinoco and Amazon river basins.
Speciation genetics: Limits and promises
Authors: Karrenberg Sophie
Published: February 2019

Many central questions on speciation genetics such as the nature of genetic changes involved and the role of selection in speciation have been under prolonged and intense debate. The development of massively parallel sequencing and increased cooperation among ecological, population and molecular geneticists, offer the promise to find answers to these questions. However, there currently is evidence for the involvement of many different factors and processes in speciation, with their relative importance unresolved. Processes implicated in speciation include not only geographic isolation and structural change through small‐effect mutations, but also regulatory mutations, copy number variation and chromosomal rearrangements, as well as scenarios of divergence‐with‐gene‐flow and evolution through genetic conflict. In this review, I summarize current views and persistent limitations in speciation genetics, explore two promising research approaches in this field and end with an overview on current and expected progress in plant speciation genetics.
A phylogenetic evaluation of Panicum sects. Agrostoidea, Megista, Prionitia and Tenera (Panicoideae, Poaceae): Two new genera, Stephostachys and Sorengia
Authors: Zuloaga Fernando O. , Scataglini M. Amalia , Morrone Osvaldo
Published: February 2019

The taxonomic features of species of Panicum, previously classified in Panicum subg. Agrostoidea and Phanopyrum including sects. Megista, Tenera, Prionitia and Agrostoidea, are reviewed and compared with subg. Panicum and other taxa of Paniceae. All taxa, previously considered in these subgenera and sections, are now included in the new genera Stephostachys and Sorengia, which are based on morphological and molecular characters. Stephostachys includes one species, S. mertensii (Roth) Zuloaga & Morrone, ranging from Mexico to Argentina, while Sorengia comprises seven species, S. anceps (Michx.) Zuloaga & Morrone, S. caricoides (Nees ex Trin.) Zuloaga & Morrone, Sorengia longifolia (Torr.) Zuloaga & Morrone S. petersonii (Hitchc. & Ekman) Zuloaga & Morrone, S. prionitis (Nees) Zuloaga & Morrone, S. stenodes (Griseb.) Zuloaga & Morrone, and S. tenera (Beyr. ex Trin.) Zuloaga & Morrone, distributed from the United States to Bolivia and Brazil. Affinities of the new genera with other genera of Paniceae are discussed. Lectotypes are designated for Panicum caricoides var. glabriusculum Döll, P. caricoides var. pilosum Döll, P. prionitis Nees, P. prionitis var. varium Kuntze, and P. stenodes Griseb.
Latin diagnoses: An unnecessary impediment — A response to Jørgensen
Authors: Figueiredo Estrela , Moore Gerry , Smith Gideon F.
Published: February 2019

We conclude that the arguments put forward by Jørgensen in his response to our recent proposal to abandon botanical Latin as the mandatory language in which to provide a description or diagnosis when a new species is described, in fact serve to confirm that this requirement must now be removed from the International Code of Botanical Nomenclature.
A molecular phylogeny and a new classification ofPyrola(Pyroleae, Ericaceae)
Authors: Liu Zhen-Wen , Zhou Jing , Liu En-De , Peng Hua
Published: February 2019

The northern temperate genus Pyrola L. is the largest and arguably the most taxonomically complex element in the tribe Pyroleae (Ericaceae). Here we present a molecular phylogenetic study with extensive sampling comprising 26 ingroup and 7 closely related taxa. The results, based on parsimony and Bayesian analyses of nuclear (ITS) and chloroplast (atpB‐rbcL, trnS‐trnG, trnL‐trnF) DNA sequences, add substantially to our understanding of relationships within this diverse group and call for taxonomic changes. Pyrola is confirmed as a monophyletic group with two redefined sections and six series: P. sect. Pyrola (P. ser. Pyrola, ser. Ellipticae and ser. Rugosae) and P. sect. Scotophylla (P. ser. Japonicae, ser. Scotophyllae and ser. Chloranthae). Members of each respective section and series share similar morphological traits and/or geographical distributions. For the potential hybrids P. media and P. faurieana, the maternal donor was identified by their close affinity to P. minor in the chloroplast trees whereas the paternal donor remained unclear.
Just what is a genus? Comparing levels of postzygotic isolation to test alternative taxonomic hypotheses in Orchidaceae subtribe Orchidinae
Authors: Scopece Giovanni , Cozzolino Salvatore , Bateman Richard M.
Published: February 2019

An exceptionally wide range of systematic data has been accumulated on subtribe Orchidinae, which dominates the European orchid flora. Despite (or perhaps because of) this wealth of information, delimitation of genera within the subtribe continues to prompt extensive debate among taxonomists. Here, we use the controversial genus Orchis s.l. as a case‐study to explore the broader issues that surround the definition and circumscription of genera, and suggest a new approach to selecting among competing formal classifications that focuses on the biological cohesion of the resulting taxa. Levels of postzygotic reproductive isolation, assessed as differential embryo mortality through extensive artificial crosses between species, are compared with three taxonomic treatments: a pre‐cladistic morphological classification permitting polyphyly; a cladistic classification generated by applying monophyly to Internal Transcribed Spacer sequences; and a 'post‐cladistic' classification that aimed to compromise between morphological and molecular differences and permitted paraphyly. The monophyletic cladistic classification is by far the most consistent with levels of postzygotic isolation through embryo mortality. Reproductive isolation, sequence divergence and morphological similarity can all usefully be quantitatively compared with formal classifications, though floral morphology in orchids offers a high risk of rapid co‐evolutionary divergence with pollinator guilds, often generating spurious monospecific 'genera'. Best practice in taxonomy reflects reciprocal illumination between key biological datasets and formal classifications, pursued in a rigorous framework of precise definitions of taxa and well‐founded evolutionary‐phylogenetic concepts.
The application of cophylogenic tools to gene sets
Authors: Baum Bernard R. , Johnson Douglas A.
Published: February 2019

Several studies of host‐parasite evolution have used gene trees developed for each partner as a means to detect the influence of one on the evolution of the other, a process known as cophylogeny. We now extend this concept and present a process to test whether two genes or gene regions within the same species have coevolved in order to assess their further utility in the same phylogenetic analysis. The process entails well‐established methods; firstly based upon a given set of sequence data, inference of best‐fit evolutionary models and associated parameters through to gene tree building by maximum likelihood. This is followed by a "ParaFit" analysis of pairwise combination of genes or gene regions. The pairwise combinations that pass the test of cophylogeny may then be horizontally concatenated for phylogenetic inference of the set of taxa under study. The complete mathematical properties of this process presently remain unexplored; however, we demonstrate the utility of such an analysis prior to phylogenetic inference using examples from available datasets.
Graphis is two genera: A remarkable case of parallel evolution in lichenized Ascomycota
Authors: Plata Eimy Rivas , Hernández M. Jesús E. , Lücking Robert , Staiger Bettina , Kalb Klaus , Cáceres Marcela E.S.
Published: February 2019

Molecular phylogenetic analysis of the mitochondrial small subunit and nuclear large subunit ribosomal DNA revealed that the lichen genus Graphis sensu Staiger represents two separate lineages. Graphis s.str. comprises the species of the G. scripta and G. subserpentina groups (‘Eugraphis’), as well as the G. striatula group sensu Lücking. For the segregate genus, the name Allographa Chevall. is available, and this genus includes the G. acharii, G. dussii, G. marginata, G. nuda, and G. symplecta groups. The separation of both lineages is supported by principal component analysis species ordination based on phenotype characters, although the G. dussii and G. subserpentina groups appear phenotypically intermediate. Species formerly placed in Hemithecium subg. Hemithecium sensu Staiger were shown to belong to at least four lineages, one nested within Graphis (H. implicatum), one within Allographa (H. chlorocarpum), one sister to Allographa (H. rufopallidum), and one nested within the Phaeographis clade (H. plicosum). Allographa is genetically close to the bulk of lirellate Graphidaceae (Diorygma, Glyphis, Pallidogramme, Phaeographis, Platygramme, Platythecium, Sarcographa, Thalloloma, Thecaria), whereas Graphis s.str. exhibits unique genetic apomorphies and takes a more isolated position.
Extensive gene flow blurs species boundaries among Veronica barrelieri, V. orchidea and V. spicata (Plantaginaceae) in southeastern Europe
Authors: Bardy Katharina E. , Schönswetter Peter , Schneeweiss Gerald M. , Fischer Manfred A. , Albach Dirk C.
Published: February 2019

Little is known about the contribution of interspecific hybridization, a frequent phenomenon in plants, to the high plant diversity in southeastern Europe, one of the continent’s diversity hot spots. A good system to study the relevance of hybridization for biodiversity in this region is Veronica subg. Pseudolysimachium sect. Pseudolysimachion (Plantaginaceae). Depending on the presumed frequency of hybridization, existing taxonomic concepts in this group range from distinguishing only morphological races without explicit taxonomic status to recognizing several species each with a series of intraspecific taxa. Using genetic (plastid sequences and AFLP fingerprints), ploidy‐level and morphometric data, three core groups, pertaining to the currently recognized species V. barrelieri, V. orchidea, and V. spicata, were identified. All three species are, however, connected by numerous and gradual genotypic transitions and show rampant discrepancies between genetic and morphometric‐taxonomic assignments. Complete homogenization of the three core groups is probably prevented by geographic isolation, ecological divergence and ploidy differences. Misinterpretation of hybrid swarms as separate taxa and the mosaic distribution of different indumentum types have led to a gross overestimation of taxonomic diversity of V. sect. Pseudolysimachion in southeastern Europe. Taxonomically, this might be accommodated by reducing V. barrelieri, V. orchidea and V. spicata to subspecific rank and abandoning recognition at least of those subspecies and varieties included in our study.
The generic concept of Lotononis (Crotalarieae, Fabaceae): Reinstatement of the genera Euchlora, Leobordea and Listia and the new genus Ezoloba
Authors: Boatwright James S. , Wink Michael , van Wyk Ben-Erik
Published: February 2019

Lotononis is a large and taxonomically complex genus of the tribe Crotalarieae, with the majority of its species occurring within southern Africa. In this study, sequence and morphological data of the rare Lotononis macrocarpa was added to existing data matrices for the Crotalarieae and these were re‐analyzed using both parsimony and model‐based (Bayesian) analyses. Molecular systematic data (nrITS and rbcL) indicated that Lotononis is polyphyletic, with Lotononis sect. Euchlora as sister to Bolusia and Crotalaria and with L. macrocarpa close to the ‘Cape’ group of the Crotalarieae. As a result, the genus Euchlora is here reinstated and the new genus Ezoloba is described herein to accommodate the anomalous L. macrocarpa. Ezoloba is distinct in its 5+5 anther configuration, exceptionally large fruit, paired stipules, minutely serrate bracts and the presence of bracteoles. Within the remaining species of Lotononis, both combined and separate analyses of the morphological and sequence datasets revealed three strongly supported clades corresponding largely to clades recovered in previous cladistic analyses based on morphological, chemical and cytological data. These are here recognised at the generic level as Lotononis s.str., Leobordea and Listia and the necessary new name combinations are formalised. Characters supporting these generic re‐alignments are discussed and a key to the 16 genera now recognized in the tribe Crotalarieae is presented.
Blastocaulon (Eriocaulaceae), a synonym of Paepalanthus: Morphological and molecular evidence
Authors: de Andrade Maria José Gomes , Giulietti Ana Maria , Harley Raymond Mervyn , van den Berg Cássio
Published: February 2019

Generic circumscription in Eriocaulaceae has been based primarily on one to few floral characters and phylogenetic relationships within the family have only recently been explored in detail. Here, we present a morphological and phylogenetic study of Blastocaulon and Paepalanthus ser. Leptocephali, based on individual and combined datasets of the psbA‐trnH plastid region and nuclear ITS. All results rejected the monophyly of Blastocaulon. Based on results and previous analyses, we propose the synonymization of Blastocaulon under Paepalanthus, the only morphological distinction between the two genera being the number of pollen‐sacs. Reduction of pollen‐sac number has occurred more than once in the evolution of Eriocaulaceae.
Who amends the International Code of Botanical Nomenclature? A response to Applequist & al. (2010)
Authors: Smith Gideon F. , Figueiredo Estrela , Moore Gerry
Published: February 2019

We maintain that a review of the way in which votes that can be cast to influence the amendment of the International Code of Botanical Nomenclature (ICBN) are allocated is overdue. Although there will no doubt be resistance to proposed changes that may emanate from such a review, a more representative system of vote allocation to herbaria, among other things, will considerably enhance the credibility and robustness of the voting system. A rebuttal addressing two criteria we suggest as examples of what could be used as part of a review to make the voting system more representative was recently published by Applequist & al. It is regrettable that in the face of unambiguous statistics that show the inadequacy of the current ICBN amendment voting system, the need for change is not embraced with due urgency. A fear of power sharing and decentralization may well be the root cause.
Genome scans reveal high levels of gene flow in HawaiianPittosporum
Authors: Bacon Christine D. , Allan Gerard J. , Zimmer Elizabeth A. , Wagner Warren L.
Published: February 2019

Species radiations in the Hawaiian Islands have resulted in closely related yet morphologically and often ecologically distinct species, many of which have highly restricted distributions. Eleven species ofPittosporum, (Pittosporaceae) are recognized in the Hawaiian Islands, yet it remains unclear whether the morphological variation within HawaiianPittosporumis due to hybridization, genetic polymorphism, phenotypic plasticity, or some combination of these processes. In this study of HawaiianPittosporumwe used a genome‐wide approach employing 626 Amplified Fragment Length Polymorphisms (AFLPs) to test species boundaries and elucidate gene flow within and among species. Parsimony trees were constructed to identify clades of individuals that correspond to species, island affinity, and/or sexual system. Network analysis was used to identify the number of lineages in the dataset; results showed a lack of resolution due to reticulation. Based on Bayesian assignment tests, HawaiianPittosporumexhibited high levels of gene flow. The interspecific allelic exchange and reticulation caused non‐hierarchical relationships between species and a lack of reproductive isolation rendered species boundaries permeable. This study highlights the impact of hybridization on species persistence and conservation as well as on general patterns of Hawaiian biota.
Phylogenetic signal of orbicules at family level: Rubiaceae as case study
Authors: Verstraete Brecht , Groeninckx Inge , Smets Erik , Huysmans Suzy
Published: February 2019

Orbicules are tiny a‐cellular sporopollenin structures that occur in the anthers of many angiosperms together with the pollen grains. Although their occurrence is common, little is known about their function and systematic usefulness. With regard to orbicules, Rubiaceae (Gentianales) are the most intensively studied plant family and therefore an ideal case to present the evolution and phylogenetic signal of orbicule characters at family level. The occurrence and morphology of orbicules was investigated in 64 species of Rubiaceae using scanning electron microscopy. Five relevant orbicule features (presence/absence, abundance, size, shape, ornamentation) were optimized onto a custom‐made phylogeny of the family. By optimizing the five orbicule characters some evolutionary trends can be observed. The previously suggested trend in angiosperms towards orbicule absence in more derived taxa is confirmed for Rubiaceae. Orbicules appear to have been independently lost at least nine times within the family, with two subsequent reversals. Small orbicules represent the plesiomorphic character state for the family. A trend from spherical towards irregular orbicules is observed, while ornamented orbicules occur only in derived lineages. Orbicule characters are constant at generic level and in most cases at tribal level, and therefore have potential for systematics. The presence of orbicules is correlated with the occurrence of a non‐amoeboid tapetum.
Erroneous identities ofPotamogetonhybrids corrected by molecular analysis of plants from type clones
Authors: Kaplan Zdenek , Fehrer Judith
Published: February 2019

Hybridization is one of the main sources of taxonomic complexity inPotamogeton. In spite of long and intensive research, the total hybrid diversity and distribution of many hybrids are still insufficiently known. Identities of two currently recognized hybrids were tested using molecular analyses of plants from the original clones growing at the type localities of their correct names. Additive characters in direct sequencing of the ITS region and the placement of cloned sequences in a Bayesian consensus tree were used to identify the exact identity of these hybrids.Potamogeton ×lanceolatifoliusis widely recognized as a hybridP. gramineus×P. polygonifolius. However, the molecular analyses and cytological investigation identified this Swedish hybrid asP. gramineus×P. nodosusalthoughP. nodosuscurrently does not occur in the whole of Scandinavia. This hybrid provides some insight into the former distribution area ofP. nodosusas affected by past climatic changes. The recently detectedP. ×vepsicuswas originally described asP. alpinus×P. natansbut the molecular investigation revealed that its correct identity isP. natans×P. praelongus. In both cases, the actual identities could hardly have been unequivocally deduced from the morphology of the hybrids. The existence of these hybrid combinations is here confirmed for the first time. The maternally inherited chloroplastrpl20-5'rps12sequences were used to identify the female parental species. The name “P. ×argutulus”, previously, but erroneously, used for a hybridP. gramineus×P. nodosus, is typified and reduced to the synonymy ofP. gramineus.
Nomenclature and typification of names of genera and subdivisions of genera in theCypereae(Cyperaceae): 3. Names in segregate genera ofCyperus
Authors: Reynders Marc , Huygh Wim , Larridon Isabel , Muasya A. Muthama , Govaerts Rafaël , Simpson David A. , Goetghebeur Paul A.
Published: February 2019

Recent molecular studies reveal thatCyperus, the core genus ofCypereae(Cyperaceae), includes several segregate genera. This paper presents a survey of all published names of subdivisions of these segregate genera ofCyperus. It is the third paper in a series of papers on the nomenclature of names of genera and subdivisions of genera inCypereae. Most names of subdivisions of genera inCypereaewere published in Kyllinga, Mariscus and Pycreus. Types are indicated, being designated where needed, and names are evaluated for their priority and legitimacy. The complex taxonomy of these genera resulted in the accumulation of 79 subdivisional names of which 20 are not validly published and two are illegitimate.
Neotypifications of Linnaean names in Hybanthus (Violaceae)
Authors: de Paula-Souza Juliana
Published: February 2019

Current studies in South American Violaceae detected the necessity of neotypes for Viola calceolaria L. (≡ Hybanthus calceolaria (L.) Oken) and Viola oppositifolia L. (≡ Hybanthus oppositifolius (L.) Taub.), names of species originally described in Loefling’s Iter Hispanicum, but without validly published names.
Report of the Nomenclature Committee for Algae: 11
Authors: Prud'homme van Reine Willem F.
Published: February 2019

It is recommended that the listed type of the genus Chlamydomonas be changed from C. pulvinus to C. reinhardtii and that the name Cylindrotheca be conserved against Ceratoneis. It is also recommended that the name Sargassum vulgare not be conserved with a conserved type. The Committee's view on the size of the current ICBN and its method of publication is discussed.
Report of the Nomenclature Committee for Fossil Plants: 7
Authors: Herendeen Patrick S.
Published: February 2019

The following eight generic names are recommended for conservation: Caytonia against Laconiella, Cupressinocladus against Libocedrites, Cyclostigma Haught. ex Heer against Cyclostigma Hochst. ex Endl., Danaeopsis Heer ex Schimp. against Marantoidea and Danaeopsis C. Presl, Eusphenopteris Gothan ex Simson‐Scharold against Eusphenopteris Kidst., Lepidophloios with that spelling, Pterophyllum with a conserved type, and Schizoneura against Convallarites. The following three species names are also recommended for conservation: Podocarpium podocarpum (A. Braun) Herend. against Podocarpium podocarpum (DC.) Y.C. Yang & P.H. Huang, Schizoneura paradoxa against Convallarites erecta, and Taeniopteris marantacea with a conserved type. The following four generic names are not recommended for conservation: Angarocarpus with a conserved type, Ephedrites with a conserved type, Genitzia with a conserved type, and Tungussocarpus (nom. illeg.). Two published proposals for conservation of generic names are still under consideration (Pleuromeia with that spelling and Sphenozamites with a conserved type).
Report of the Nomenclature Committee for Algae: 13
Authors: Prud'homme van Reine Willem F.
Published: February 2019

The following two proposals for modification of the International Code of Botanical Nomenclature that relate particularly to algae are recommended for acceptance: Rec. 8B Prop. A (Taxon Prop. 138), Art. 9 Prop. H (219), and the following two are not recommended for acceptance: Art. 13 Prop. B (165), Art. 36 Prop. B (170). The Committee was undecided on Art. 45 Prop. A (150). In addition the Committee did not recommended acceptance of Gen. Prop. Prop. A (016). The Committee also recommended that the ICBN continues to be published in its entirely as a printed book (cf. Art. 14 Prop. G–I (098–100)).
Report of the Nomenclature Committee for Fossil Plants: 8
Authors: Herendeen Patrick S.
Published: February 2019

The following three sets of proposals for modification of the International Code of Botanical Nomenclature that relate particularly to fossil plants are recommended for acceptance: Gen. Prop. Prop. C, Art. 1 Prop. A & B (Taxon Prop. 101–103), Art. 9 Prop. H (219), and Art. 38 Prop. A (192), and the following three sets are not recommended for acceptance: Art. 1 Prop. C & D (175–176), Art. 8 Prop. B, Art. 9 Prop. U, & Art. 38 Prop. C (135–137), and Art. 38 Prop. B (193). In addition the Committee considered a number of proposals of general impact and recommended acceptance of Art. 29 Prop. A–C, Art. 30 Prop. A–B, Art. 31 Prop. A–B, Rec. 29A Prop. A–B, & Rec. 30A Prop. A–B (203–213), the proposals on electronic publication, and Div. III Prop. B–C (199–200), but the Committee was undecided on the associated proposals Div. III Prop. D–E (201–202). Although not directly affecting names of fossil plants, the Committee also discussed Art. 36 Prop. A–E (115, 170, 186–188) on the language requirements for the validation of names of new taxa. The members had a positive view of the experience of the restrictive language requirement of either English or Latin for names of fossil plants and would not wish to see a return to allowing any language for validating diagnoses or descriptions.
Apoptotic effects of cigarette smoke extracts on mouse embryonic stem cells via oxidative stress
Authors: Kim Cho‐Won , Go Ryeo‐Eun , Hwang Kyung‐A. , Jeung Eui‐Bae , Choi Seong‐Jin , Choi Kyung‐Chul
Published: February 2019

Abstarct

Previous studies have reported that cigarette smoke and cigarette smoke extract (CSE) have negative effects on embryonic development. However, no studies have investigated the mechanism through which CSE affects the cellular signaling pathway leading to apoptosis and oxidative stress in embryonic cells, or how the two pathways are cross‐linked. Thus, we studied the effects of CSE on apoptosis and oxidative stress in mouse embryonic stem cells (mESCs). Specifically, we measured changes in cell viability in response to CSEs (3R4F and two domestic cigarettes CSE 1 and 2) using a water soluble tetrazolium (WST) assay and a neutral red uptake (NRU) assay, which revealed that cell viability decreased in a concentration‐dependent manner. Western blot analysis revealed that the expression of cyclin D1 and cyclin E1 was decreased and that of p21 and p27 was increased by CSE. Additionally, the number of terminal deoxynucleotidyl transferase (TUNEL)‐stained cells was increased by CSE, while the levels of Bax and Caspase‐3 increased and Bcl‐2 decreased. Moreover, a 2′,7′‐dichlorofluorescin diacetate (DCF‐DA) assay and reactive oxygen species (ROS)‐Glo H2O2 assay confirmed that ROS were generated in response to CSE and that they were associated with up‐regulated Keaf‐1 and CHOP. Overall, the results revealed that cigarette smoke extract (CSE) inhibited cell proliferation by regulating cell cycle‐related protein expression and increased oxidative stress by regulating the expression of Kelch‐like ECH‐associated protein 1 (Keap‐1) and CCAAT/enhancer‐binding protein homologous protein (CHOP), resulting in apoptosis in mESCs.
20,000 years of societal vulnerability and adaptation to climate change in southwest Asia
Authors: Jones Matthew D. , Abu‐Jaber Nizar , AlShdaifat Ahmad , Baird Douglas , Cook Benjamin I. , Cuthbert Mark O. , Dean Jonathan R. , Djamali Morteza , Eastwood Warren , Fleitmann Dominik , Haywood Alan , Kwiecien Ola , Larsen Joshua , Maher Lisa A. , Metcalfe Sarah E. , Parker Adrian , Petrie Cameron A. , Primmer Nick , Richter Tobias , Roberts Neil , Roe Joe , Tindall Julia C. , Ünal‐İmer Ezgi , Weeks Lloyd
Published: February 2019

The Fertile Crescent, its hilly flanks and surrounding drylands has been a critical region for studying how climate has influenced societal change, and this review focuses on the region over the last 20,000 years. The complex social, economic, and environmental landscapes in the region today are not new phenomena and understanding their interactions requires a nuanced, multidisciplinary understanding of the past. This review builds on a history of collaboration between the social and natural palaeoscience disciplines. We provide a multidisciplinary, multiscalar perspective on the relevance of past climate, environmental, and archaeological research in assessing present day vulnerabilities and risks for the populations of southwest Asia. We discuss the complexity of palaeoclimatic data interpretation, particularly in relation to hydrology, and provide an overview of key time periods of palaeoclimatic interest. We discuss the critical role that vegetation plays in the human–climate–environment nexus and discuss the implications of the available palaeoclimate and archaeological data, and their interpretation, for palaeonarratives of the region, both climatically and socially. We also provide an overview of how modelling can improve our understanding of past climate impacts and associated change in risk to societies. We conclude by looking to future work, and identify themes of “scale” and “seasonality” as still requiring further focus. We suggest that by appreciating a given locale's place in the regional hydroscape, be it an archaeological site or palaeoenvironmental archive, more robust links to climate can be made where appropriate and interpretations drawn will demand the resolution of factors acting across multiple scales.

This article is categorized under:

Human Water > Water as Imagined and Represented

Science of Water > Water and Environmental Change

Water and Life > Nature of Freshwater Ecosystems
Aqueous cadmium removal with ferrate: Influencing factors, removal mechanism, and effect of coexisting ions
Authors: Wang Hongbo , Zhang Ru , Li Haining , Li Mei , Wang Yonglei , Zhao Qian , Wang Ning
Published: February 2019

The aim of the work was to evaluate the potential of potassium ferrate (K2FeO4, Fe(VI)) removing Cd(II) from aqueous solution and to primarily investigate the mechanism. Batch experiments were carried out to evaluate the influence of various factors including dosage of K2FeO4, solution pH, the initial concentration of Cd(II), and coexisting ions. The results showed that increasing dosage of K2FeO4 benefited the removal of Cd(II) with the efficiency up to 98.97%. The enhanced removal occurring at higher pH could be attributed to less self‐decomposition of K2FeO4 under alkaline conditions. The maximum specific removal capacity was 80 mg/(g K2FeO4) under certain conditions. Surface properties of the Cd(II)‐containing precipitations were characterized, and the results showed that the weakly crystalline ferrihydrite derived from self‐decomposition of Fe(VI) benefited the adsorption capacity, and Cd(II) was removed via the adsorption of the hydrolysate nanoparticles. Moreover, the coexisting ions were found weakening the removal efficiency of Cd(II) due to the restricted activity of K2FeO4 and competition for adsorption sites of hydrolysate. The interaction between the hydrolyzed products and the adsorbed Cd(II) was also weaken by compressing the thickness of the electric double layer because of the presence of coexisting ions.

Practitioner points

Removing Cd(II) from aqueous solution as high as 98.97%.

Removal efficiencies of Fe(VI) relied on chemical dose, pH and contaminant concentration.

Co‐exiting ions weaken the removal efficiency, such as Ca2+ and SO42‐ as well as ionic strength.
Synthesis and Characterization of New N‐Heterocyclic Silylazides
Authors: Dyckhoff Florian , Kaiser Felix , Hölzl Sebastian , Kühn Fritz E.
Published: February 2019

Three novel pyridine functionalized N‐heterocyclic silanes, bearing chloride and azide moieties, were synthesized and characterized by NMR spectroscopy (1H, 13C, 29Si), mass spectrometry, elemental analysis, and single‐crystal XRD. The molecular structures show a comparably strong dative interaction of the pyridine‐N with the Si center, formally inducing a penta‐coordination arrangement at the silicon(IV). Under appropriate conditions, the silylazides, presented in this work, might be able to thermo‐ or photolytically liberate gaseous nitrogen giving rise to a promising synthetic option to access a variety of new transition metal silylene complexes with potential applications in various catalytic reactions.
Ergonomics in handheld and robot-assisted camera control: a randomized controlled trial
Authors: Wijsman Paul J. M. , Molenaar Lennert , van‘t Hullenaar Cas D. P. , van Vugt Bas S. T. , Bleeker Wim A. , Draaisma Werner A. , Broeders Ivo A. M. J.
Published: February 2019

Background

Laparoscopic surgery potentially increases the physical burden to operating theater personnel and can cause physical discomfort. This study aims to evaluate if a robotic camera holder (AutoLap™ system) can improve ergonomics for the surgeon and the camera assistant during laparoscopic procedures.

Methods

A total of thirty cases were included and randomized (15 AutoLap™, 15 control). Five types of surgery were included: right hemicolectomy, fundoplication, sigmoid resection, rectopexy, and low anterior resection. The posture of the surgeon and assistant was photographed during predefined steps of the procedure. MATLAB was used to calculate angles relevant for the RULA score. The RULA score is a validated method to evaluate body posture, force and repetition of the upper extremities. Two investigators assessed the RULA score independently. Three subjective questionnaires (SMEQ, NASA TLX, and LED) were used to assess mental and physical discomfort.

Results

No differences in patient characteristics were observed. Sixteen fundoplications, seven right hemicolectomies, five sigmoid resections, one rectopexy, and one low anterior resection were included. The mean RULA score of the surgeon was comparable in both groups, 2.58 (AutoLap™) versus 2.72 (control). The mean RULA score of the assistant was significantly different in both groups, with 2.55 (AutoLap™) versus 3.70 (control) (p = 0.001). The inter-observer variability (ICC) was excellent with 0.93 (surgeon) and 0.97 (assistant). The questionnaires showed a significant difference in physical discomfort for the assistant. The LED and SMEQ score were significantly lower in the robotic group. The NASA TLX demonstrated a significant reduction in scores in all domains when using robotics with the exception of the mental domain.

Conclusion

Use of the AutoLap™ system shows improvement in ergonomics and posture of the first assistant, and ergonomics of the surgeon are not affected. Furthermore, the subjective work load is significantly reduced by using a robotic camera holder.

Trial registration number

NCT0339960, https://clinicaltrials.gov/ct2/show/study/NCT03339960?term=autolap&rank=5.
High-Stakes Testing Case Study: A Latent Variable Approach for Assessing Measurement and Prediction Invariance
Authors: Culpepper Steven Andrew , Aguinis Herman , Kern Justin L. , Millsap Roger
Published: February 2019

The existence of differences in prediction systems involving test scores across demographic groups continues to be a thorny and unresolved scientific, professional, and societal concern. Our case study uses a two-stage least squares (2SLS) estimator to jointly assess measurement invariance and prediction invariance in high-stakes testing. So, we examined differences across groups based on latent as opposed to observed scores with data for 176 colleges and universities from The College Board. Results showed that evidence regarding measurement invariance was rejected for the SAT mathematics (SAT-M) subtest at the 0.01 level for 74.5% and 29.9% of cohorts for Black versus White and Hispanic versus White comparisons, respectively. Also, on average, Black students with the same standing on a common factor had observed SAT-M scores that were nearly a third of a standard deviation lower than for comparable Whites. We also found evidence that group differences in SAT-M measurement intercepts may partly explain the well-known finding of observed differences in prediction intercepts. Additionally, results provided evidence that nearly a quarter of the statistically significant observed intercept differences were not statistically significant at the 0.05 level once predictor measurement error was accounted for using the 2SLS procedure. Our joint measurement and prediction invariance approach based on latent scores opens the door to a new high-stakes testing research agenda whose goal is to not simply assess whether observed group-based differences exist and the size and direction of such differences. Rather, the goal of this research agenda is to assess the causal chain starting with underlying theoretical mechanisms (e.g., contextual factors, differences in latent predictor scores) that affect the size and direction of any observed differences.