bluuebunny/crossref_metadata_2025 huggingface dataset:
Pollination by megachilid bees and determinants of fruit‐set in the Cape orchid Disa tenuifolia
Authors: Johnson S. D. , Steiner K. E.
Published: March 2008

Wild‐fires near Cape Town, South Africa, stimulated mass‐flowering in several populations of Disa tenuifolia (Orchidaceae). We found that the bright yellow flowers of the orchid are pollinated by various carder and leafcutter bees (Megachilidae) and occasionally monkey beetles (Scarabaeidae: Hopliini). The highly elongate pollinaria become attached to the underside of the pollinator's thorax. The bees showed strong fidelity towards the orchid, despite the lack of nectar in its flowers. The orchid does not appear to mimic other rewarding species. It was concluded that the pollination system of D. tenuifolia depends on exploitation of instinctive foraging and territorial behaviour of male megachilid bees. The fruiting success of D. tenuifolia at the study site was pollinator‐limited as supplementary hand‐pollinations resulted in a two‐fold increase in the percentage of flowers which set fruit.
A new species of Tephrosia (Leguminosae) from southern Yemen, with a note on the identity of T. geminiflora
Authors: Thulin Mats
Published: March 2008

Tephrosia hadramautica, a new species from the coastal plain of Hadramaut in southern Yemen, is described and illustrated. T. geminiflora, previously regarded as an endemic of Hadramaut, is reduced to a synonym of T. suhtriflora.
A new species of Clausena (Rutaceae) from India
Authors: Stone Benjamin C. , Nair K. Narayanan
Published: March 2008

Southern Indian plants hitherto identified as Clausena heptaphylla by Gamble have been found to differ consistently in several features from that species and are here distinguished as C. austroindica n.sp. Description, relationships, relevant comparisons, habitat, variation, and specimens examined are given.
The genus Morinda (Morindeae, Rubioideae, Rubiaceae) in New Caledonia: taxonomy and phylogeny
Authors: Johansson Jan Thomas
Published: March 2008

The genus Morinda (Morindeae, Rubioideae. Rubiaceae) is closely allied to Coelospermum, Gynochthodes, and Pogonolobus, but differs from these genera in inflorescence and pollen morphology. In this revision of Morinda in New Caledonia fourteen species are recognized, one of which is subdivided into four varieties. Eleven species are endemic to the area. Two new species, M. mumtana and M. truneata, and one new variety, M. myrtifolia var. vrevifolia, are described. Two recombinations, M. myrtifolia var. choriophylla and M. myrtifolia var. velutina, are made. All taxa are illustrated with line drawings and their distributions mapped, and a key to the species is presented. Phylogenetic analyses including nineteen species are presented.
Developmental and comparative ultrastructure of glandular hairs in the two Urticaceae. I. Urtica dioica
Authors: Vassilyev A. E.
Published: March 2008

Secretion produced by glandular hairs is deposited mainly in the periplasmic space of the head cells. It stains intensely for both proteins and polysaccharides. The ultrastructure of meristematic, differentiating, mature and senescent head cells as well as the stalk and basal cells has been described in comparison to that in other cell types of the leaf. The specific features of the head cells are the proliferation of the granular endoplasmic reticulum as well as the multiplication of the dictyosomes and mitochondria during transition to the secretion stage. However, the frequency of dictyosomes varies among secreting hairs. The ER produces neither secretory nor transition vesicles and does not anastomose with the plasmalemma. In the absence of transition vesicles, the transport of secretory proteins and enzymes of polysaccharide synthesis from the ER to dictyosomes apparently includes the cytosolic step. Dictyosomes, though not appearing hypersecretory, produce two types of smooth secretory vesicles generated by the trans Golgi reticulum. The vectorial transfer of prosecretion and membranes across the dictyosome stack proceeds via the transport (shuttle) vesicles. It is, therefore, concluded that exocytosis of smooth secretory Golgi vesicles is the sole mechanism of release of both proteins and polysaccharides. Coated vesicles occasionally seen near the plasmalemma are likely to be involved in the endocytotic membrane retrieval. The secretion product disappears during senescence of the hairs and the secretory cells undergo vacuolation by means of local autophagy.
Response to mowing of coastal brackish meadow plant communities along an elevational gradient
Authors: Vestergaard Peter
Published: March 2008

Over a six year period, 1979–1985, eight stands of till then ungrazed and unmown brackish meadow plant communities were treated by mowing once a year (August), in order to detect the response of the vegetation. The stands were distributed along a local elevation gradient, which was found to influence the composition of the vegetation through a complex‐gradient, composed by unidirectional gradients in inundation, in ground water level and in Na as per cent of Ca+Mg+Na+K.

The mowing was carried out within 5 ×5 m treatment plots and the effect was indicated by quantitative analysis of the vegetation. A natural succession progressing at the locality, most distinctly manifested by expansion of Phragmites australis, was traced during the study period by means of unmown control plots.

The mowing caused increase in species diversity in all stands, mainly due to increase in evenness among the species.

The resistance of the stands to the mowing was found to differ in relation to elevation and to the initial composition of the vegetation. In upper geolittoral Festuca rubra stands the resistance was high and the mowing did not affect presence or colonisation of Phragmites. In upper‐middle Festuca rubra stands resistance was lower, mainly indicated by suppression of Phragmites. Low elevation Scirpus maritimus reed beds on waterlogged soil was rather resistant, but four additional years of mowing led to a change into Agrostis stolonifera‐Puccinellia maritima meadow. The resistance of low elevation Phragmites reed bed was low, as the mowing within a few years changed the reed bed into Agrostis stolonifera meadow.

The results were discussed in relation to the use of mowing as a nature conservation management tool in salt meadows.
Andropogon crispifolius (Poaceae: Andropogoneae): a new species from the cerrado of central Brazil
Authors: II Gerald F. Guala , Filgueiras Tarcico S.
Published: March 2008

Andropogon crispifolius a new species from the environs of the Parque Nacional das Emas (in the states of Goiás and Mato Grosso do Sul) in central Brazil is here described, illustrated and compared with A. pohlianus Hack. It is a large, perennial, coarse grass characterized primarily by its strongly crispate older leaves. This new species is placed in sect. Notosolen Stapf, previously represented in South America by a single species, A. pohlianus.
Succession and soil development in man‐made coastal ecosystems at the Baltic Sea
Authors: Andersen Ulla Vogt
Published: March 2008

By the creation of Køge Bay Seaside Park in 1978 the opportunity was given to study the establishment of vegetation and primary succession in a man‐made coastal area. As the soil consists of marine material from the Baltic Sea, no organic matter or seedbank was present. The first steps of primary succession were followed in 1980, when the initial inventories of flora immigration and soil development were carried out in coastal grasslands and plantings. The surveys were repeated in 1992 and 1993. Except for the planted woody species and a few sown grasses, all other species of plants have reached the area through natural dispersal of diaspores. The total number of species in the permanent plots has increased from 26 in 1980 to 91 in 1993. The results indicate that this number will continue to increase in the coming years until a certain level. Then it will probably decrease as a result of competition from woody species, unless the vegetation is kept in a steady state by disturbances or management. Today the area is very far from the initial situation, and the off‐shore barrier has changed towards a landscape dominated by small groves and grasslands of an urban common type.
Observations of hawkmoth pollination in the South African orchid Disa cooperi
Authors: Johnson S. D.
Published: March 2008

Johnson, S. D. 1995. Observations of hawkmoth pollination in the South African orchid Disa cooperi. ‐ Nord. J. Bot. 15: 121–125. Copenhagen. ISSN 0107–055X.

Disa cooperi is a robust grassland orchid with long‐spud white flowers which are strongly scented in the evening. Observations at a site in Natal province, South Africa showed that hawkmoths are frequent visitors to the orchid at dusk. The hawkmoth Basiothia schenki was an effective pollinator of D. cooperi; this hawk‐moth has a medium length proboscis (x = 4.3 cm) which can be fully inserted into the nectar‐containing spur of the orchid. Pollinaria are attached ventrally to the basal portion of the proboscis where it joins the head. Another hawkmoth, Agrius convolvuli, commonly foraged on nectar from D. cooperi, but did not carry pollinaria, probably because its proboscis is too long (x = 10 cm) to allow contact between the thick basal portion of the proboscis and the orchid column. Lips in Disa are typically linear and do not produce scent, thus the autapomorphic spathulate and scent‐producing lip of D. cooperi indicates that hawkmoth pollination is derived in this species, probably from a long‐proboscid fly pollinated ancestor.
Five new species of the genus Liparia (Fabaceae) from South Africa
Authors: Schutte Anne Lise
Published: March 2008

Schutte, A.L. 1995. Five new species of the genus Liparia (Fabaceae) from South Africa. ‐ Nord. J. Bot. 15: 149–156. Copenhagen. ISSN 0107–055X.

Five distinct new species of the genus Liparia are described, namely L. bonaespei, L. confusa, L. congesta, L. rafnioides and L. triata. These species are, like many of the species included in the recently enlarged generic concept of Liparia, also localized, and are all endemic to the Cape Province of South Africa.
Two new taxa of Pogostemon (Lamiaceae) from India
Authors: Kumar V. Sampath , Sharma B. D.
Published: March 2008

Kumar, V. S. & Sharma, B. D. 1995. Two new taxa of Pogostemon (Lamiaceae) from India. ‐ Nord. J. Bot. 15: 163–166. Copenhagen. ISSN 0107–055X.

A new species Pogostemon hedgei and a new variety P. speciosus var. filiformis, are described from South India. Both belong to sect. Pogostemon.
Distribution of internal secretory structures in Tagetes patda (Asteraceae)
Authors: Poli Ferruccio , Sacchetti Gianni , Bruni Alessandro
Published: March 2008

Poli, E, Sacchetti, G. & Bruni, A. 1995. Distribution of internal secretory structures in Tagetes parula (Asteraceae). ‐ Nord. J. Bot. 15: 197–205. Copenhagen. ISSN 0107–055X.

Seedlings and flowering plants of Tagetes patula present secretory reservoirs similar to many other Asteraceae which produce poly acetylenes. These poly acetylene reservoirs (PRs) that contain both thiophenes and essential oils, show a blue‐yellow fluorescence and a red colour when observed in the UV and conventional microscope respectively. In the root of the seedlings two arrays of six PRs arise abutting on the endodermis. PRs of branch roots are connected to those in the parent roots. A single layer of “epithelial” non‐specialised cells forms the secretory tissue. In the hypocotyl four PRs, characterised by a uniseriate epithelium, arise in the cortex in front of the vascular bundles. In the epicotyl, instead, we found eight PRs localised between the vascular bundles. In the cotyledons, in the leaves and in the flower bracts there are only secretory cavities. In the flowering plant, PRs also occur in the corolla of the tubular and ligulate flowers of the inflorescence, with a typically biseriate epithelium.
Mallomonas madagascariensis, M. lemuriocellata and M. crocodilorum (Synurophyceae), three new species from Madagascar
Authors: Hansen Peer , Kristiansen Jørgen
Published: March 2008

Hansen, P. & Kristiansen, J. 1995. Mallomonas madagascariensis, M. lemuriocellata and M. crocodilorum (Synurophyceae), three new species from Madagascar. ‐ Nord. J. Bot. 15: 215–223. Copenhagen. ISSN 0107–055X.

Mallomonas madagascariensis, M. lemuriocellata and M. crocodilorum are described and illustrated with TEM micrographs as the first results of studies of silica‐scaled chrysophytes made in Madagascar. Their taxonomical position within the genus Mallomonas (sect. Torquatae, ser. Mangoferae) is discussed and morphological distinguishing characters are presented.
Effect of altitude on the sex ratio in populations of Silene acaulis (Caryophyllaceae)
Authors: Alatalo Juha M. , Molau Ulf
Published: March 2008

Alatalo, J. M. & Molau, U. 1995. Effect of altitude on the sex ratio in populations of Silene acaulis. — Nord. J. Bot. 15: 251–256. Copenhagen. ISSN 0107–055X.

Predicted increase of female frequencies in gynodioecious Silene acaulis was tested along an altitude gradient in northern Sweden. Average female frequencies for the four sites increased with altitude from 42% to 59% within a short geographical distance. This follows the outcrossing hypothesis, that female frequencies should be positively correlated with selfing rates of hermaphrodites in populations. More adverse environmental conditions should favour gynodioecy in areas where reproduction to a greater part relies on vegetative reproduction or selfing. Further, a significant difference in corolla width was found between females and the larger hermaphrodites, but not between sites. Cushion size and the number of flowers per cushion decreased with attitude.
The genus Hedychium (Zingiberaceae) in Thailand
Authors: Sirirugsa Puangpen , Larsen Kai
Published: March 2008

Sirirugsa, P. & Larsen K. 1995. The genus Hedychium (Zingiberaceae) in Thailand. ‐Nord. J. Bot. 15: 301–304. Copenhagen. ISSN 0107–05513.

Three new species of Hedychium from Thailand are described and illustrated, H. samuiense, H. tomentosum, and H. biflorum. A key to the species occurring in Thailand is provided.
Reaction of some decomposer basidiomycetes to toxic elements
Authors: Høiland Klaus
Published: March 2008

Høiland, K. 1995. Reaction of some decomposer basidiomycetes to toxic elements. ‐Nord. J. Bot. 15: 305–318. Copenhagen. ISSN 0107–055X.

Cultures of 15 decomposer basidiomycete samples were examined for resistance to Al. As, Be, Cd, Co, Cr, Cu, H, Hg2(I), Hg(II), Ni, Pb, Sn, and Zn using a micro‐well technique. Aluminium was found to be slightly toxic; Be, Zn, and As moderately toxic; Cr, Cu, Sn, Co, Hg(II), Ni, Hg2(I), and Pb toxic: and Cd very toxic. Generally, the fungitoxicity rises with increasing electronegativity of the element, if we exclude As and Cd. According to the fungal reactions, the elements can be arranged into several groups with similar toxicity: The Cu‐Hg2(I)‐Hg(II)‐Ni group, the Al‐Cr‐H group, and the As‐Pb‐Zn group. Tin is related both to the first and the second group. Beryllium, Cd, and Co occupy more isolated positions. Resistance to Hg, Ni, and Cu generally increases with the ability of the fungus to produce phenoloxidases, especially the intracellular tyrosinase. One explanation may be that these fungi decompose the substances that actually bind Hg, Ni, and Cu and hence protect them from the toxic action. Resistance to A1 and H (expressed as pH) may be higher in fungi from poor soils. The physiological effect of soluble A1 on fungi seems to depend more on its ability to release H3O+ in the medium than on the toxic action of the metal itself. On the other hand, resistance to Cd is possibly higher in fungi from rich soils, probably because toxicity of Cd usually increase with pH.
The lichen genus Phaeophyscia in China and Russian Far East
Authors: Moberg Roland
Published: March 2008

Moberg, R. 1995. The lichen genus Phaeophyscia in China and Russian Far East. ‐Nord. J. Bot. 15: 319–335. Copenhagen ISSN 0107–055X.

Fifteen species, more than half of the total known species in the lichen genus Phaeophyscia, are shown to be present in China and Russian Far East. Morphology, anatomy, chemistry, distribution, habitat, relations to other taxa and some evolutionary trends are discussed. A key to the species is presented and regional distribution maps of all species are given. Several species are new to the area. New combinations are: Phaeophyscia endococcina var. endococcinodes and Phaeophyscia hispidula var. exornatula. The following names are reduced to synonymy: Phaeophyscia endococcinodes, Physcia endococcinodes var. megalospora, Physcia endococcinodes var. stellata, Phaeophyscia imbricata, Phaeophyscia exornatula, Phaeophyscia limbata, and Physcia endococcina var. latiloba.
Cytological and morphological differentiation in Caralluma burchardii (Asclepiadaceae)
Authors: Meve U.
Published: March 2008

Meve, U. 1995. Cytological and morphological differentiation in Carallurna burchardii (Asclepiadaceae). — Nord. J. Bot. 15: 459–467. Copenhagen. ISSN 0107–055X.

Caralluma burchardii is revised based on detailed investigations of vegetative and floral morphology, as well as chromosome numbers. The species is now divided into two taxa, the dodecaploid ssp. burchardii, an endemic of the Canary Islands, and ssp. rnaura, a hexaploid from the west coast of Morocco. The high ploidy levels involved, the highest known in the Asclepiadaceae, are discussed in conjunction with biogeographical aspects.
The Iranian species of Allium subg. Melanocrommyum sect. Megaloprason (Alliaceae)
Authors: Fritsch Reinhard M.
Published: March 2008

Analyses of newly collected, living materials from the “classical locations” led to taxonomic conclusions differing from the last comprehensive treatment by Wendelbo in the “Flora Iranica”: Allium bakhtiaricum is a good species characterised by reticulate bulb tunics; it is rather widely distributed in the Zagros mountain range. In Allium jesdianum reticulate bulb tunics are missing, and it occurs only in the mountains near Yazd. Both taxa possess a scape which is prominently ribbed in its lower part. On the contrary, Allium stipitatum (syn. A. hirtifolium) has a scape completely smooth in the living stale, and bulb tunics disintegrating in fibre‐like parts. Allium altissimum, which is only doubtfully recorded for Iran, and some other taxa formerly included within sect. Megaloprason by Wendelbo, were not seen as living plants; their classification is shortly discussed. A new key to sect. Megaloprason s. str. is given.
Revision of the genus Diplotaxis (Brassicaceae) in the Cape Verde Islands, W Africa
Authors: Rustan Øyvind H.
Published: March 2008

The genus Diplotaxis (Brassicaceae) in the Cape Verde Islands, W Africa, is revised. Nine taxa are accepted, of which five are described as new: D. antoniensis sp. nov., D. glauca, D. gorgadensis sp. nov., D. gorgadensis ssp. brochmannii ssp. nov., D. gracilis, D. hirta, D. sundingii sp. nov., D. varia sp. nov., and D. vogelii. All species are suffruticose, yellow‐flowered perennials and belong to sect. Catocarpum. The species are endemic to the Cape Verde Islands, but show morphological and karyolog‐ical affinity to the N African and Mediterranean D. harra s. lat. Analyses of morphological variation in 90 populations (400 plants) revealed a complex pattern, in particular in vegetative characters, most likely evolved by parallel ecogeographical differentiation in different islands. The chromosome number is 2n = 26 (n = 13) in the five taxa investigated. Self‐pollination experiments indicate that the species are self‐incompatible and outcrossing. Experimental F1 hybrids with full seed set after open pollination were obtained in 30 interspecific combinations, and the taxa are considered fully interfertile. The taxa are thus isolated mainly by geographical and partly by ecological barriers and have evolved by vicariant evolution (most islands) and adaptive radiation (one island).
A species‐poor tropical sedge community: Afrotrilepis pilosa mats on inselbergs in West Africa
Authors: Porembski Stefan , Brown Gary , Barthlott Wilhelm
Published: March 2008

The mat‐forming poikilohydric sedge Afrotrilepis pilosa (Cyperaceae) occurs as the dominant member of characteristic stands on West African inselbergs. The species composition of this community has been examined in the Ivory Coast along a latitudinal gradient from the savanna to the rainforest region. Inselbergs consisting of Precambrian granites and gneisses, are prominent landscape elements characterized by large areas of exposed rock. Monocotyledonous mats are one of the most conspicuous communities of this ecosystem. Floristically, the mats are poor in higher plant species with a total of only 15 species (mostly therophytes) recorded in 110 relevés. Species diversity is likewise low, indicating extremely stressful environmental conditions. A major factor affecting plant colonization is the pronounced short‐term variation in water‐availability, even in the more humid regions in the south of the country. Afrotrilepis pilosa is highly competitive under these conditions, and the dense stands leave only little space for other species to become established. Longevity (attaining an age of several hundred years) and the ability, to spread radially to form almost monospecific stands are further characteristics which render this species a superior competitor. In marked contrast with most other tropical vegetation types, Afrotrilepis mats have therefore to be regarded as an example of a naturally occurring, extremely species‐poor community, in which competitive displacement and the low degree of disturbance prevent higher diversity.
Calamintha cretica (Lamiaceae), a Cretan endemic: Distribution and essential oil composition
Authors: Karousou R. , Kokkini S. , Bessière J‐M. , Vokou D.
Published: March 2008

The distribution of Calamintha cretica, a taxon restricted on the massif of Levka Ori (White Mountains W. Crete, Greece), is presented. The essential oils of three populations were examined by means of GC and GC‐MS. The essential oil yield varied from 0.5% to 1.9%, whereas the major compounds were in all cases piperitenone oxide (26.4–41.3%) and piperitone oxide (33.8–59.9%). Like all other Calamintha taxa examined to date, it is a species rich in p‐menthane compounds. The results are further discussed in relation to their chemotaxonomic value.
A new species of Microcharis (Leguminosae) from Somalia
Authors: Thulin Mats
Published: March 2008

The new species Microcharis omissa, from the sandstone escarpment near Yasoomman in central Somalia, is described. This apparently narrow endemic is closely related to M. sessilis in north‐eastem Somalia.
A new species of Zehneria (Cucurbitaceae) from Somalia
Authors: Thulin Mats
Published: March 2008

The new species Zehneria somalensis, from shady limestone rocks in north‐eastem Somalia, is described and illustrated.
Erythroxylon (Erythroxylaceae) on Socotra
Authors: Thulin Mats
Published: March 2008

Erythroxylon socotranum, sp. nov., is described from limestone rocks on southwestern Socotra (Yemen). The species is the first representative of Erythroxylaceae to be known from Socotra and from South‐West Asia in general.
Some taxonomic corrections in the subtribe Bulbophyllinae (Orchidaceae)
Authors: Vermeulen Jaap J.
Published: March 2008

Garay, Hamer and Siegerist (1994) propose numerous new taxa and combinations in the genus Bulbophyllum. Their opinions are often contradicting those expressed in Vermeulen (1991, 1993a. 1993b). A reason for this can be sought in the different basic principles both authors apply when delimiting species and higher taxonomic entities. Some of the taxa proposed by Garay, Hamer and Siegerist (1994) are analysed, and taxonomic changes are proposed.
Vegetation‐environment relationships of old‐growth spruce forest vegetation in Østmarka Nature Reserve, SE Norway, and comparison of three ordination methods
Authors: Rydgren K.
Published: March 2008

The relationship between vegetation and environmental variables has been studied in 100 sample plots, each 0.25 m2, in old‐growth spruce forest at Høgkollen, ØOstmarka Nature Reserve, SE Norway. Each sample plot was supplied with measurements of 13 environmental and 5 biotic variables. Parallel application of three ordination techniques, PCA, DCA and LNMDS, resulted in different sample plot configurations. PCA performed poorest due to strong influence of outliers and circumstantial evidence indicated better performance of LNMDS than DCA. Statistical analyses of the relationships between vegetation and ecological data revealed a parallel gradient in soil moisture (decreasing) and canopy closure (increasing) as the most important for differentiation of the vegetation. Species number and field layer cover decreased, while bottom layer cover increased, due to increasing cover ofDicranum majus, with decreasing soil moisture and increasing canopy closure. Constrained canonical correspondence analysis (CCA) was used to partition the variation of the species‐sample plot matrix into spatial, environmental and unexplained variation, and combinations. The fraction of unexplained variation was high (80.9 %), most likely due to small sample plot size and short gradient lengths. Most of the explained variation was attributable to environmental factors alone (54.5%). Only 6.3% was shared between environmental and spatial variation, which indicated minor importance of broad‐scale and geographically structured environmental variation. Strictly spatial variation constituted 39.3%. However, the spatially structured environmental variation was low, so the causes of spatial variation were likely not to be found among the measured environmental variables.
Ichthyostoma ‐ a new genus in the Amthaceae from NE tropical Africa
Authors: Hedrén M. , Vollesen K.
Published: March 2008

Ichthyostoma thulinii, a new genus and species from Central Somalia and SE Ethiopia is described. Ichthyostoma is best placed in Acanthoideae ‐ Odontoneminae, but is not closely related to any extant genus in that group.
Geonoma irena (Arecaceae), a new species from western Ecuador
Authors: Borchsenius Finn
Published: March 2008

A new palm species, Geonoma irena from western Ecuador, is described and illustrated. It is separated from the polymorphic G. cuneata on the basis of differences in floral morphology, associated with major differences in flowering biology.
Soil chemistry and plant distributions in rock habitats of southern Sweden
Authors: Tyler Germund
Published: March 2008

The vascular plant flora of open land on superficial bedrock in southem Sweden (northwards to 59°N) is described and related to soil chemical properties. including soil acidity (pH), exchangeable Al, Ca, Fe, Mn, Mg, and phosphate, as well as to soil solution pH and concentrations of Al, Ca and Mg, and to the contents of soil organic matter, soil depth and bedrock types (sandstone, gneiss, granites, various dark igneous rocks and limestones). About 120 localities with totally 652 sites (4 m2) have been examined. Experimental evidence for the toxicity of acid soils and mineral nutrient deficiency of neutral and alkaline soils is related to field data. Hydrogen and Al ion toxicity in acid soils and low phosphate solubility in neutral ‐ alkaline soils are identified as major factors limiting the field distributions of rock habitat plants. Some species (e.g., Rumex acetosella and Sedum telephium) were limited by phosphate also in acid soils. The relative importance of H and Al ion concentrations to plant performance under variously acid soil conditions is discussed, and strong evidence is given for a decisive influence of Al ion toxicity on species diversity at pH‐KCI > 4.5. The importance of grazing and former land use is considered briefly and the floristic differences between the western and the eastern half of the study area are discussed originating from differences in general distribution patterns of species and soil chemical properties.
Vessel origin in Cabomba
Authors: Schneider Edward L. , Carlquist Sherwin
Published: March 2008

Tracheary elements of the nodal plexus in stems of Cabomba aquatica and C. caroliniana have pores in the primary wall as seen with scanning electron microscopy (SEM); these pores are adjacent to the helical thickening bands. Presence of the pores qualifies these tracheary elements as vessel elements, in agreement with our previous criteria in Nymphaeaceae, but the vessel elements differ from any hitherto described for vascular plants and thereby enhance the likelihood of polyphylesis of vessels in dicotyledons.
A remarkable new species of Bulbophyllum, sect. Wpudianthes from Thailand
Authors: Seidenfaden Gunnar
Published: March 2008

A new species, Bulbophyllurn guttifilum is described from Thailand.
Dichilanthe, an unusual Asiatic Rubiaceae with “Lonicera flowers” and “dipterocarp fruits”
Authors: Puff C. , Buchner R. , Igersheim A.
Published: March 2008

Dichilanthe, a disjunctly distributed, arborescent Southeast Asiatic genus (D. zeylanica: Sri Lanka; D. borneensis: West Borneo) with collar‐like, persistent stipules, has strongly zygomorphic, ornithophilous flowers which show secondary pollen presentation. The curved corolla is two‐lipped. The upper lip consists of 2, and the lower lip of 3 fused corolla lobes. The calyx, too, is zygomorphic. The curved, exserted style ends in a swollen “stylar head' which apically bears two small stigmatic (receptive) areas in a zygomorphic arrangement. The flowers are borne in compact, terminal heads, held together by enlarged stipules of a bract‐pair immediately below the inflorescence. The dispersal units (diaspores) mimic dipterocarp fruits. They consist of a persistent, wing‐like pair of bracts whose±cuplike stipules enclose the fruits. The diaspores break off at the node immediately below the bract‐pair, where there is a distinct abscission zone. Initial on”primary“dispersal by wind may be followed by facultative”secondary“dispersal by floating in water.”Pith tissue“produced by each fruit of the diaspore, and the air spaces contained therein, are likely to be adaptations to floating. This”pith tissue“, a loose, parenchymatic,± irregularly arranged area of the fruit wall which partially disintegrates during fruit maturation, represents a modified portion of the endocarp; the remainder of the endocarp is”normal“sclerenchymatic tissue coating the two locules. The initial stages of this endocarp differentiation are already observable in early developmental stages, i.e., in ovaries of flower buds and open flowers. The bicarpellate ovaries contain a solitary, anatropous pendulous ovule per locule. Viable seeds have large embryos and only c. 5–6 layers of oily endosperm; their exotesta cells have delicate, ring‐like thickenings. In developing fruits of individual inflorescences, a high frequency of seed abortion was noted. Not uncommonly, there is only a single viable seed per dispersal unit, i.e., only a solitary seedling emerging from a diaspore. Germination of the seeds is cryptocotylar. The pollen of D. zeylanica is suboblate and 5‐ or 6‐colpate (with the colpi being rather short); the exine is finely reticulate. In spite of several of its character states being unusual and aberrant, the tribal position of Dichilanthe in the Guettardeae is not questioned, although it is concluded that the genus occupies a rather isolated position in the tribe.
Chrysophyte stomatocyst assemblages associated with periphytic, high arctic pond environments
Authors: Wilkinson Anna N. , Zeeb Barbara A. , Smol John P. , Douglas Marianne S. V.
Published: March 2008

Chrysophycean stomatocysts associated with three different periphytic substrates (wet mosses, submerged mosses and rock scrapes) were investigated from ponds on Cape Herschel (78°37'N, 74°42'W), Ellesmere Island in the Canadian High Arctic. The goal of this study was to determine whether a distinct assemblage of periphytic chrysophyte cysts existed and, if so, whether assemblage composition varied with substrate and between ponds. One hundred and thirty‐seven different cyst morphotypes were observed with light microscopy from 68 periphytic samples taken from 35 ponds. Twenty‐six of these cysts were new morphotypes, of which 16 were identified and described using scanning electron microscopy. Significantly more cyst types with collars and hooked projections in the collar region (i.e. ‘hooked’), and fewer unomamented morphotypes were recorded in the periphytic habitats as compared to the surface sediments. Wet moss stomatocyst assemblages were particularly distinct, with a high number of heavily silicified and hooked morphotypes. The morphotype richness was far greater in periphytic environments, with 86, 100 and 95 morphotypes observed in the wet mosses, submerged mosses and rock scrapes, respectively, as compared to only 35 types in the surface sediments of the ponds. Canonical correspondence analysis indicated that measured water chemistry did not account for the variation in the species data (paxic 1 < 0.01, 999 Monte Carlo permutations). This study suggests that distinct periphytic assemblages exist, and that cyst morphotype composition and richness varies with substrate.
Floral character states of the Northeast and Tropical East African Swertia species (Gentianaceae)
Authors: Nemomissa Sileshi
Published: March 2008

The floral gross morphological and anatomical character states of 23 African Swertia species are described. Colleters are frequent in Swertia, especially at the lower rim of calyx lobes and are usually placed in a single row except in S. crassiuscula (they are not “typical” colleters). The aestivation of corolla lobes is found to be uniform except in S. engleri var. engieri. Each corolla lobe is beset with either one or two foveae. Foveae are naked or either partly or wholly fimbriated along their margins. No vascular tissue was observed entering the foveae. The taxonomic importance of the the floral character states is discussed.
The hypothesis of hybrid origin of Poa jemtlandica supported by morphometric and isoenzyme data
Authors: Brysting A. K. , Elven R. , Nordal I.
Published: March 2008

Morphometric and isozyme data were used to test the hypothesis that the pseudoviviparous Poa jemtlandica has originated as a hybrid between the sexual P flexuosa and the facultative apomict P alpina. Plants were sampled from three localities in southern Norway. In addition, some Icelandic plants were included. Both morphometric and isozyme data clearly support the hybrid hypothesis. Poa jemtlandica was morphologically intermediate between its supposed parents in several individual characters as well as in a discriminant analysis. Seven enzyme systems were analysed. Eight areas of activity were interpreted as “loci”, each of which certainly represented several duplicated genes in these plants which all are polyploid. A total of 27 different multilocus phenotypes was observed: ten phenotypes in P alpina var. vivipara, eight phenotypes in I. alpina var. alpina, seven phenotypes in P jemtlandica, and three phenotypes in P flexuosa. The phenotype of Icelandic P jemtlandica was identical to that of P. jemtlandica from one of the Norwegian localities. Additive electrophoretic patterns were observed for P jemtlandica at four individual “loci”. At the remaining “loci” some phenotypes of P. jemtlandica were most similar to P. flexuosa, others to P alpina. The data also suggest that P jemtlandica has originated several times, but there is no indication of frequent or recent hybridization where the species coccur today.
Age‐related growth and reproduction in Diapensia lapponica, an arctic‐alpine cushion plant
Authors: Molau Ulf
Published: March 2008

Growth and flowering in an evergreen, cushion‐forming, circumpolar, arctic‐alpine plant, Diapensia lapponica, was followed for five years, 1990–1994, at the Latnjajaure Field Station, northern Swedish Lapland. This species is unusually suitable for age determination since plants grow radially from a central point of initiation. During the study period, the radial annual radial growth of cushions averaged 0.6 mm. The species exhibited a sigmoid pattern of growth in relation to the estimated age of cushions, and at least 400–year old plant individuals are present within the study area. Plants of Diapensia become reproductive at an average age of about 18 years, and may continue to flower for centuries. Recruitment to the seedling population takes place during cold periods (sequences of cold summers), and there is a negative correlation between recruitment and mean annual temperature in the Abisko area since 1913. The oldest stock of the present population at Latnjajaure was recruited during the Little Ice Age.
A floral ontogenetic investigation of the Hydrangeaceae
Authors: Roels P. , Decraene L. P. Ronse , Smets E. F.
Published: March 2008

As a first step towards a broader floral ontogenetic study on Cornales, the flowers of four species of Hydrangeaceae (Deutzia corymbosa, Kirengeshoma palmata, Philadelphus purpurascens and Hydrangea petiolaris) were studied. In Deutzia and Kirengeshoma five sepal primordia are generally initiated, in Philadelphus only four. Sepal initiation in Kirengeshoma shows a tendency to tetramony. Deutzia has a variable sepal initiation. Petal growth was never retarded in the studied species. Initiation of the androecium in Kirengeshoma, Philadelphus and Hydrangea starts with antesepalous primary primordia, on which secondary primordia are soon formed, leading ultimately to the formation of polystaminate androecia. In Deutzia a diplostemonous androecium is formed, starting with the initiation of the antesepalous stamen primordia. Gynoecium development is similar in all species studied: on a concave floral apex, a ring meristem is initiated; it develops into a variable number of continuous carpel primordia, while the centripetally growing common margins form the septa. Initiation of the ovule primordia starts halfway up each placenta and extends in an apical, basal and lateral direction. A number of morphological problems are discussed, such as the derivation of tetramery, and evolutionary and developmental trends in the androecium and gynoecium. Kirengeshoma is well settled in Hydrangeaceae, although its exact position within the family remains uncertain. A sistergroup relationship of Hydrangeaceae with Loasaceae is supported. However, Hydrangeaceae also share features with Saxifragaceae (e.g. similar gynoecium development).
Synopsis of the genus Ladenbergia (Rubiaceae)
Authors: Andersson Lennart
Published: March 2008

Ladenbergia is a neotropical genus of the tribe Cinchoneae. It is recognized by the combination of septicidal capsules, usually large, winged seeds, heterostylous flowers, presence of terminal inflorescence, and distally ridged corolla lobes. Although widely distributed in tropical Central and South America, it is heavily centered in the Andes. It is hypothesized that the ancestral area was in the premontane zone of the central Andes. Thirty‐four species are recognized in this revision, but several more are represented in herbaria by material that is too incomplete for formal description. Seven species are described as new: L. dwyeri, L. nuhigena (Panama); L. klugii (Peru); L. lehmanniana, L. magdalenae, L. obovata, and L. pauccflora (Colombia). A key to the species is given, the new species are described, and distribution maps are provided for all species.
A revision of Centella series Capenses (Apiaceae)
Authors: Schubert Mahalia T. R. , van Wyk Ben‐Erik
Published: March 2008

Centella capensis (L.) Domin and related species form a distinct but poorly known group within the genus. The most conspicuous diagnostic feature is the unique inflorescence structure. Each umbel comprises a central umbellule reduced to a single, sessile, functionally female flower and four lateral, functionally male, pedicellate umbellules each reduced to a single flower. The umbel is surrounded by four large, foliaceous bracts. Another unusual character is the habit. Most of the species are annuals or short‐lived perennials, while all other species of the genus are perennial shrublets. A taxonomic revision of the four species and three varieties recognized, is presented.
A new species and a new record of Tephrosia (Leguminosae) from Socotra
Authors: Thulin Mats
Published: March 2008

Tephrosia socotrana sp. nov., a woody species growing on limestone cliffs in north‐central Socotra (Yemen), is described and illustrated. strigosa is recorded from Socotra and Yemen for the first time.
A new species of Coelogyne (Orchidaceae) from Arunachal Pradesh, India
Authors: Chowdhery H. J. , Pal G. D.
Published: March 2008

A new species of Coelogyne, C. arunachalensis from Arunachal Pradesh, is described.
Oreopanax (Araliaceae) in Ecuador
Authors: Borchsenius Finn
Published: March 2008

Oreopanax is represented by twenty species in Ecuador. The morphological basis for their classification is briefly discussed. A key to the species is provided. A description of each species is given. Six species are described as new (Oreopanax grandifolius, O. impolitus, O. microflorus, O. obscurus, O robustus, and 0. trifidus), while nine names with type in Ecuador are reduced to synonyms.
A revision of the genus Anginon (Apiaceae)
Authors: Allison Izelle , van Wyk Ben‐Erik
Published: March 2008

Anginon, a hitherto poorly known genus of woody Apiaceae endemic to southern Africa, is revised. Field studies over several years have shown that 12 species can be recognised, of which five are newly described: A. ternatum, A. fruticosum, A. pumilum, A. tenuior and A. intermedium. The new combination A. streyi is made to transfer Sonderina streyi to Anginon, with which it shares the woody habit and heavily cutinised outer cell walls of the fruit epidermis. A formal taxonomic treatment is presented, including a key to the species, correct nomenclature, typification, descriptions and distribution maps.
Bolboschoenus glaucus (Cyperaceae), with emphasis upon Africa
Authors: Browning J. , Gordon‐Gray K. D. , Smith S. Galen , van Staden J.
Published: March 2008

Investigations into the pericarp anatomy of southern African representatives of the polymorphic species Bolboschoenus maritimus s.l. (Scirpus maritimus s.l.) indicated that two entities were present. One of these, Bolboschoenus glaucus, has had a history of inclusion and exclusion from B. maritimus. This historical aspect is surveyed, and a species description and distribution map based on African material are given. Illustrations of the type, and of an example of achene morphology and pericarp anatomy of B. glaucus are provided.
Lyrella cassiteridum, a new species of marine epipelic diatom
Authors: Mann David G.
Published: March 2008

Lyrella cassiteridumsp. nov. is described from the Isles of Scilly, SW Britain. It is an epipelic species and was found in samples taken from marine sandflats in the intertidal and uppermost subtidal zones. In LM,L. cassiteridumis most similar toL. abrupta, from which it can be distinguished by its larger size and coarser structure. The ultrastructure of the frustule is documented and discussed with respect to that of otherLyrellaspecies and the related genusPetroneis.A brief review of the nomenclatural history ofLyrellais given.
Taxonomic continuum of Alchemilla (Rosaceae) in Estonia
Authors: Sepp Silvia , Paal Jaanus
Published: March 2008

23 widespread apomictic Alchemilla microspecies occurring in Estonia are analyzed to investigate whether the species and higher rank taxa are distinct, how variable these taxa are and which characters distinguish them better. Cluster analysis, discriminant analysis, analysis of variance, principal component analysis and continuum analysis are used for data processing. The characters form four correlative groups, describing (i) vegetative and (ii) generative parts of the plant body, (iii) hairiness characters and, (iv) leaf teeth measurements. The best characters according to analysis of variance for disünguishing species are hairiness characters, but often they distinguish only few species very clearly and cannot be used for the remaining ones. Hence the other characters cannot be excluded. From the studied species only A. plicata, A. semilunaris and A. lindbergiana are significantly distinct from all others. The remaining ones form a complicated network of mutually indistinct pairs. Higher rank taxa — sections and series according to Rothmaler, Fröhner and Yuzepchuk are better separated, containing very few mutually indistinct pairs. Results from species centroids' clustering are most congruent with Fröhner's system, but still some changes seem to be necessary and a corrected system is proposed here. Section Plicatae is split into two series: Pubescentes and Barbulatae, sections Alchemilla, Ultravulgares and Decumbentes are joined as three series of section Hirsutae, and A. filicaulis is moved from section Plicatae to section Coriaceae. Coriaceae should also be split into three series: Exuentes (A. filicaulis), Glabricaules (A. glabricaulis) and Coriaceae (other species).
A description of Mallomonas marsupialis nov. sp. (Synurophyceae), a new chrysophyte from Australia, with comments on the endemicity of Australian freshwater algae
Authors: Croome Roger , Kristiansen Jørgen , Tyler Peter A.
Published: March 2008

Mallomonas marsupialis is described and illustrated by TEM and SEM micrographs, being found in Australia on sub‐tropical Fraser Island and in cool‐temperate Tasmania. Its taxonomic location within the genus Mallomonas (sect. Mallomonopsis, ser. Marsupiales) is discussed, together with its inclusion in a suite of unusual endemic algae which have been described from Australian sites largely protected from human interference.
Dombeya kefaensis, sp. nov. (Sterculiaceae) from SW. Ethiopia
Authors: Friis I. , Bidgood S.
Published: March 2008

Dombeya kefaensis Friis & Bidgood sp. nov., is described from a mosaic of humid montane forest, forest margins, evergreen bushland and farmland of the Kefa Region, SW. Ethiopia. The new species belongs to a group of species in Dombeya subgen. Dombeya with several other endemics in that part of Ethiopia. Among the Ethiopian species of Dombeya subgen. Dombeya it resembles especially D. aethiopica in indumentum and flower colour, but differs in leaf‐morphology and habit; it resembles D. buettneri in habit, but differs in the leaf apex being broadly acute to rounded, the sepals and petals longer, and the style having a notable indumentum in more than the basal half. Recent studies have confirmed that a number of taxa belonging to other genera and families are restricted to the Kefa Region and adjacent parts of SW. Ethiopia which confirms the importance of the area as a local centre of diversity.
The comparative ecology of Polystichum aculeatum, P. braunii, and P. lonchitis in Hordaland, western Norway
Authors: Mütter H. , Birksand H. J. B. , Odland A.
Published: March 2008

The comparative ecology of the three species of Polystichum in Hordaland, western Norway, has been studied. Species frequency data and environmental variables were recorded in 132 sample units from 10 different localities. The numerical methods used to analyse these data are two‐way indicator species analysis, detrended correspondence analysis, canonical correspondence analysis, and Gaussian logit regression. The main floristic gradient in the data is closely related to altitude. The second floristic gradient follows patterns in precipitation and soil pH. The ordination and classification results show that P. braunii is primarily a plant of deciduous forests, P. aculeatum occurs in open or woodland habitats near the coast, and P. lonchitis favours open habitats with cool summers at either low or high altitudes. The Gaussian logit regression results suggest that low altitude, short distance from the coast, and high soil pH may be important in influencing the growth of P. aculeatum, whereas P. braunii appears to depend most strongly on high soil depth and humidity and an adequate but not too extensive snow‐cover in winter. P. lonchitis is found to favour high soil and air humidity, high light intensity, and not too high summer temperatures. The results contribute to our understanding of the local, national, and European distributions of the three species. In western Norway, conditions appear to be generally favourable for P. braunii and P. lonchitis, but are clearly less favourable for P. aculeatum