Notes on Colura Crenulata (Lejeuneaceae, Marchantiophyta), a New Record for Thailand, with a Sporophyte Description

Colura crenulata Grolle (Lejeuneaceae), a rare and poorly known species from Papua New Guinea, Sumatra and Borneo, was newly discovered in tropical montane forests in southern Thailand. It is characterized by its acutely mamillose lobule sac and perianth; apical crest of the lobule sac consisting of 1–5 cells; large valve composed of 18–21 hyaline margin cells and 20–29 median cells, with a single median basal cell; and nearly entire dorsal margin of the leaf. This species is described and illustrated in detail, and its diagnostic characters and a comparison with the related species are briefly treated.