Subjects: Biology >> Botany >> Applied botany submitted time 2021-06-02 Cooperative journals: 《广西植物》
Abstract： A new species, Selaginella pseudotamariscina (Selaginellaceae), is described from Vietnam. The placement of this species within Selaginella subg. Stachygynandrum is assessed based on a molecular phylogenetic analysis and morphological comparisons with related species. Molecular phylogenetic analyses suggested that S. pseudotamariscina is sister to S. digitata-S. imbricata clade. Morphologically, the new species is similar to S. tamariscina and S. pulvinata by sharing the rosette-forming habit, but distinguished by its dorsal leaves symmetrical, lanceate, sulcate on upper surface; strobili slightly dorsiventrally complanate and non-resupinate, sporophylls resembling vegetative leaves in form and arrangement, non-resupinate, the ventral sporophylls larger than the dorsal ones, dorsal sporophylls sterile, sporangia only borne on the base of ventral sporophylls.
Subjects: Biology >> Botany >> Applied botany submitted time 2021-04-13 Cooperative journals: 《广西植物》
Abstract： Gongga Mountain is the highest peak of Hengduan Mountains and is an adequate site to study species diversity and the successive distribution of species along altitude. In this study we present an account of the species diversity and floristic characters of lycophytes and ferns in Gongga Mountain based on field survey, specimens identification, and literatures reviewing.The results were as follows: A total of 316 species of 60 genera in 26 families of lycophytes and ferns were recognised in this study. Of these species, six species are assessed to be rare and endangered and need special protection in China. They are Isoëtes hypsophila, Psilotum nudum, Alsophila spinulosa, Aleuritopteris albofusca, Polystichum glaciale and Lepisorus palmatopedatus. Of the fern flora in this mountain, the largest four families are Dryopteridaceae (75 species), Polypodiaceae (56 species), Pteridaceae (54 species), and Athyriaceae (37 species); The largest four genera are Polystichum (45 species), Dryopteris (24 species), Athyrium (24 species), and Lepisorus (19 species). Temperate species are the dominant floristic elements (286 species, 93.77%) in this mountain. With the ascending of the elevation from 1 000 to 3 000 m, the species diversity gradually increases, which reaches the highest at the zone between 2 000–3 000 m where 192 species (belonging to 60 genera in 20 families) were recorded; Above 3 000 m, the species diversity declines, with only four species found over 4 500 m. When viewing the floristic elements, the Sino-Himalaya species are found to be gradually increased along the ascension of elevations.
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