Taxonomic Study of Genus Fimbristylis Vahl. (Cyperaceae) in Nepal

Abstract

The genus Fimbristylis Vahl (Cyperaceae Juss.) is composed of about 300 taxa and there are significant taxonomic issues with both Fimbristylis and the tribe Abildgaardieae, and there is no agreement on the boundaries and morphological delimitation of these taxa or the species therein. No comprehensive and detailed taxonomic work has been done on the genus Fimbristylis. Altogether 23 species of Fimbristylis are recorded in Nepal. The present study was conducted to carry out the detailed taxonomic treatment of this genus based on morphology, distribution and phenology. The study was conducted from the specimens deposited at KATH, TUCH and Online herbarium: BM, E, K and TI, along with the personal collections as far as possible. Out of 23 species of Fimbristylis, 18 species are described based on the study of live plants and herbarium specimens, the remaining five are described based on the study of herbarium specimens deposited at different herbaria and review of relevant literatures. Abildgardia, Bulbostylis and Fimbristylis genera are frequently picked out together because they are highly similar to one another and can only be distinguished by "minor" characteristics, which are frequently visible only under a powerful lens. Fimbristylis is distinguished by the lack of perianth bristles in the flower and lack of a persistent style base on the nut. The genus Fimbristylis has various economic importance as it provides food, fodder, medicines, fibres used in making hats, handbag, basket, cushion and mats. They also have environmental uses as soil improvers whereas some are considered as agricultural weeds. Taxonomic keys were prepared for the quick identification of the species. With the help of IBM SPSS version 23.0 Hierarchical cluster analysis was done where Dendogram was prepared using morphological character and character states where two main clusters were formed based on presence and absence of leaf blades. Similarly different sub clusters were formed based on various morphological characters, which shows the close and distant relationship among the species. Based on the herbarium and personal collection the species are distributed from 70m – 3200m. Both vegetative and reproductive characters play a crucial role in delimitation of the taxa. The taxa are delimited based on the characteristics of root, culms, leaves, inflorescence type, spikelets, glumes, style, stigma number and nutlets.