Taxonomic realignments and new records of Gongylanthus and Southbya (Marchantiophyta: Southbyaceae) from the Sino-Himalayan region
Váa, Jií; Grolle, Riclef; Long, David G.
The family Southbyaceae is here re-established, rearranged and validated. A key is provided to the two Sino-Himalayan genera of Southbyaceae, Gongylanthus and Southbya, comprising three regional species, Gongylanthus himalayensis Grolle (= G. indicus S. C. Srivast. et P. K. Verma, syn. nov.), Southbya organensis Steph. (= S. grollei N. Kitag., syn. nov.) and S. gollanii (Steph.) Grolle. A revised concept and description of S. gollanii is provided, based on recent fertile collections and re-study of types. Past confusion in the delimitation and synonymy of these species is clarified. For each, the regional and world distributions are given, based on literature reports along with a list of confirmed but previously unreported collections from the study area. An ecological summary of each species is presented showing some differences in habitat preferences. The report of Gongylanthus ericetorum (Raddi) Nees from the study-area (China) is rejected and G. himalayensis is reported as new to Sichuan Province. Southbya gollanii is reported as new to Bhutan and to China from Yunnan Province (previous reports from China refer to Gongylanthus himalayensis and Southbya organensis). Under each genus a conspectus of extra-regional taxa is appended. Gongylanthus pringlei Underw. is reduced to the synonymy of G. muelleri (Gottsche) Steph. Worldwide, nine species of Gongylanthus and four species of Southbya are recognized.