Revision of the neotropical species of Triplophyllum (Tectariaceae)

This paper re-examines the species of Triplophyllum in the neotropics. The indument of the laminae (hairs and glands) provides many characteristics for distinguishing the species. Nine species are recognized, including three new ones: T. boliviense, T. chocoense, and T. glabrum. New combinations are made for T. hirsutum and T. perpilosum . A key is provided to distinguish the species, and all species are described and illustrated. The spores of the neotropical species are like those from African and Madagascan species. As such, they offer no evidence to determine whether the neotropical species form a monophyletic clade within the genus.     

Epiphytic ferns and bryophytes of Tasmanian tree‐ferns: A comparison of diversity and composition between two host species

Abstract Ferns, bryophytes and lichens are the most diverse groups of plants in wet forests in south‐eastern Australia. However, management of this diversity is limited by a lack of ecological knowledge of these groups and the difficulty in identifying species for non‐experts. These problems may be alleviated by the identification and characterization of suitable proxies for this diversity. Epiphytic substrates are potential proxies. To evaluate the significance of some epiphytic substrates, fern and bryophyte assemblages on a common tree‐fern species, Dicksonia antarctica (soft tree‐fern), were compared with those on a rare species, Cyathea cunninghamii (slender tree‐fern), in eastern Tasmania, Australia. A total of 97 fern and bryophyte species were recorded on D. antarctica from 120 trunks at 10 sites, and 64 species on C. cunninghamii from 39 trunks at four of these sites. The trunks of C. cunninghamii generally supported fewer species than D. antarctica, but two mosses (particularly Hymenodon pilifer) and one liverwort showed significant associations with this host. Several other bryophytes and epiphytic ferns showed an affinity for the trunks of D. antarctica. Species assemblages differed significantly between both sites and hosts, and the differences between hosts varied significantly among sites. The exceptionally high epiphytic diversity associated with D. antarctica suggests that it plays an important ecological role in Tasmanian forests. Evidently C. cunninghamii also supports a diverse suite of epiphytes, including at least one specialist species.     

Fern species richness along a central Himalayan elevational gradient, Nepal

Aim The study explores fern species richness patterns along a central Himalayan elevational gradient (100–4800 m a.s.l.) and evaluates factors influencing the spatial increase and decrease of fern richness. Location The Himalayas stretch from west to east by 20°, i.e. 75–95° east, and Nepal is located from 80 to 88° east in this range. Methods We used published data of the distribution of ferns and fern allies to interpolate species elevational ranges. Defining species presence between upper and lower elevation limit is the basis for richness estimates. The richness pattern was regressed against the total number of rainy days, and gradients that are linearly related to elevation, such as length of the growing season, potential evapotranspiration (PET, energy), and a moisture index (MI = PET/mean annual rainfall). The regressions were performed by generalized linear models. Results A unimodal relationship between species richness and elevation was observed, with maximum species richness at 2000 m. Fern richness has a unimodal response along the energy gradients, and a linear response with moisture gradients. Main conclusions The study confirms the importance of moisture on fern distributions as the peak coincides spatially with climatic factors that enhance moisture levels; the maximum number of rainy days and the cloud zone. Energy‐related variables probably control species richness directly at higher elevations but at the lower end the effect is more probably related to moisture.     

Ethnobotanical studies on some pteridophytes of Southern Nigeria

Southern Nigeria represents one of the richest zones of vegetational wealth of Nigeria. The land surface is dominated by plants under 200 m.a.s 1. Folk utilization of pteridophytes by the southern Nigerians was studied. The results of this survey display an interesting diversity and distribution of ferns and fern-allied plants used as medicines, food, cosmetics, and manure in southern Nigeria. The data were compiled from frequent field trips conducted in 40 local government areas (LGAs). A total of 36 plant species belonging to 22 families were identified. Plant specimens and information were collected directly from the local inhabitants in villages and periurban towns. Our literature survey showed little or no documentation of ethnobotanical studies on pteridophytes of this region. Therefore, the present communication serves to bridge the gap. Thus, these pteridophytes could provide a vital source for healthcare and economic revenue after appropriate pharmacological analysis by patents.     

Comparison of molecular and morphological data on St Helena: Elaphoglossum

The endemic elaphoglossoid ferns, Elaphoglossum dimorphum, E. nervosum and Microstaphyla furcata of St Helena, form a closely related group within section Lepidoglossa when analysed phylogenetically using sequences from the chloroplast trnL intron (partial) and trnL-F intergenic spacer. Microstaphyla furcata, traditionally placed in its own genus, is clearly shown to belong to Elaphoglossum confirming the previous transfer of this species to Elaphoglossum as E. bifurcatum. There is hardly any trnL-F sequence divergence between the species, in fact sequences of E. nervosum and E. dimorphum are identical. These results are consistent with the possible origin of E. dimorphum as a hybrid between E. bifurcatum and E. nervosum or with the view that the three species are the result of a recent radiation. The potential conflict between phylogenetic and morphological distinctness in determining species conservation priorities is discussed.     

茂兰国家级自然保护区石松类和蕨类植物区系特征

本研究通过野外考查、标本采集和分类鉴定，以及文献资料整理，对贵州茂兰国家级自然保护区石松类和蕨类植物区系组成和分布区类型进行统计分析。结果显示：(1)茂兰国家级自然保护区共有石松类和蕨类植物32科76属237种，优势科为鳞毛蕨科(Dryopteridaceae)、蹄盖蕨科(Athyriaceae)、凤尾蕨科(Pteridaceae)、水龙骨科(Polypodiaceae)；优势属为双盖蕨属(Diplazium)、卷柏属(Selaginella)、凤尾蕨属(Pteris)。(2)分布区类型以东亚广布和热带亚洲分布为主，生态类型以阴生植物和土生植物居多。(3)与其他地区的区系比较显示，茂兰与广西花坪物种相似性系数最高，依次是贵州梵净山、四川峨眉山和云南马关县。     

Observations on bipolar disjunctions of moonwort ferns (Botrychium,Ophioglossaceae)

Peter Raven, in 1963, included two fern taxa of the genus Botrychium in his list of plant species exhibiting American amphitropical bipolar disjunctions. He attributed the southern hemisphere occurrences to post‐Pleistocene long‐distance dispersal from counterparts in the northern hemisphere, probably assisted by annual bird migrations between the disjunct areas. Using genetic evidence gathered through worldwide analyses of phylogenetic relationship in Botrychium, we now review and reconsider Raven's conclusions. Genetic similarities indicate that South American Botrychium dusenii is an allotetraploid taxon closely related to B. spathulatum, a North American endemic, and that B. lunaria in New Zealand possesses a genotype identical to that of a taxon in North America derived through introgressive hybridization between B. lunaria and an endemic North American species, B. neolunaria. Both North American counterparts exhibit Raven's characteristics of bipolar disjuncts in their occurrence in mountain and coastal meadows, copious production of small propagules (spores in Botrychium), occurrence in habitats frequented by transpolar bird migrants, and ability to found new colonies through inbreeding. We discuss these characteristics in Botrychium and relative to other ferns and suggest further studies on Botrychium and related taxa to address questions of time, number, and mode of bipolar dispersals.