การศึกษาทบทวนพืชชั้น Marchantiopsida ในประเทศไทย

Abstract

A taxonomic study of the class Marchantiopsida in Thailand is presented, based on the materials from field surveys in various phytogeographical regions of the country from June 2012 to October 2014 as well as the herbarium specimens from AAU, BCU, BK, BKF, CMU, EGR, G, HSNU, JE, KLU, L, NICH, M, PSU and SING herbaria. Twenty-one species are recognized including 10 new records viz. Asterella mussuriensis (Kashyap) Verd. subsp. mussuriensis, Cyathodium cavernarum Kunze, C. foetidissimum Schiffn., C. mehranum D.K. Singh., C. smaragdinum Schiffn. ex Keissl., C. tuberculatum Udar & D.K. Singh, C. tuberosum Kashyap, Lunularia cruciata (L.) Dumort. ex Lindenb., Plagiochasma appendiculatum Lehm. & Lindenb., and P. cordatum Lehm. & Lindenb. Two species are excluded from Thai Marchantiopsida records, i.e. Asterella blumeana (Nees) Kachroo and Monosolenlum tenerum Griff. Thai species are mostly growing on soil and rocks, but are also found on decaying wood and base of tree trunks. The total altitudinal range of the class extends from near sea level to over 2500 m in elevation. The greatest diversity of Marchantiopsida in Thailand is found in the Northern region with 20 species. Cyathodium cavernarum Kunze, Riccia billardieri Nees & Mont., and R. fluitans L are the most common species and widely spread in Thailand, distributed in all seven floristic regions, while several species have a restricted distribution in only one particular floristic region. A key to species, brief descriptions and selected illustrations of the species are provided. In addition, the spore morphology through scanning electron micrographs and notes on the ecology and geographical distribution of the species are presented.