Taxonomic study of the family daltoniaceae (Bryophyta) in thailand

Abstract

A taxonomic study of the family Daltoniaceae Schimp. in Thailand is presented, based on the materials from field surveys in various floristic regions of the country from January 2014 to December 2016 as well as the herbarium specimens from BCU, BKF, CMUB, HYO, PSU, and SING herbaria. Twenty-two species and three varieties in five genera are recognized, namely Calyptrochaeta Desv., Daltonia Hook. & Taylor, Distichophyllum Dozy & Molk., Ephemeropsis K.I.Goebel, and Leskeodon Broth. Of these, three species are newly recorded for Thailand viz. Distichophyllum obtusifolium Thér., D. osterwaldii M. Fleisch. and D. subnigricaule Broth. Three species are excluded from Thai flora: Daltonia carinata (Dixon & W.E. Nicholson) B.C. Ho & L. Pokorny, Distichophyllum decolyi Gangulee, and D. obovatum (Griff.) Paris. A key to species, descriptions and illustrations are provided. Habitats, ecology, and geographical distribution of the species are also noted. Among the currently recognized taxa of Daltoniaceae in Thailand were collected from various habitats such as rocks, soils, trunks, twigs and living leaves. The majority of the species are epiphytes either corticolous or ramicolous. The total altitudinal range of the family extends from near sea level to over 2000 m in elevation. The lower montane rain forests at altitudes between 800 and 1600 m contain the highest species numbers. The greatest diversity of Thai Daltoniaceae is found in the Peninsular region with 14 species 3 varieties, followed by 10 species in the Northern region. Calyptrochaeta remotifolia (Müll. Hal.) Z. Iwats. et al. is the most common species and widely spread in Thailand which is distributed in five floristic regions.