Turczaninowia (Dec 2017)
Taxonomic studies of lycophytes and ferns from the Pan-Himalaya (II): Crepidomanes, Didymoglossum and Vandenboschia (Hymenophyllaceae)
Abstract
The ferns family Hymenophyllaceae is one of the most interesting basal clades of ferns, which is widely distributed in tropical and subtropical regions, less common in temperate latitudes of both hemispheres. This work deals with the taxonomic study of the representatives of the subfamily Trichomanoideae, which according to the classification of PPG 1 (2016) in the region are represented only by three genera. Following the style of the treatment of the genus Hymenophyllum, this paper is the second report of our studies of the filmy ferns from the Pan-Himalaya which is a part of the ongoing “Flora of Pan-Himalaya” project. In the present account, the taxonomy of three genera of Hymenophyllaceae: Crepidomanes, Didymoglossum, and Vandenboschia from the Pan-Himalaya are carefully revised based on morphological characters and recent works in the region. Herbarium materials kept in the National Herbarium (PE) have been fully studied and compared with collections from the Himalayas kept in European herbaria (K, BM, E). The generic and infrageneric classifications follow those of Ebihara et al. (2006) which recognized only nine genera. In the Himalayas, only four genera represented, i. e., Hymenophyllum (10 species), Crepidomanes (5 species), Didymoglossum (1 species), and Vandenboschia (2 species). The synopsis includes a key for species identification, standard taxonomic citations for the genus, sections, species. For each taxon as well as of each synonym are verified and indicated, necessary literature citation, morphology descriprion and citation of the reprehensive specimens from the Pan-Himalaya are recorded, overall distribution is mentioned and distribution in the Flora of Pan-Himalaya area is mapped. Although this is only a precursor of the ongoing “Flora of Pan-Himalaya” project, it is useful for identification of new collections from the area, and provides basic information for the conservation and ecological studies of the filmy ferns from the Himalayas, a very sensitive area to global changes. Crepidomanes parvifolium and Didymoglossum sublimbatum in this region are critical endangered concerning their small populations and limited distribution.
