On Lepicolea Dumort. (Marchantiophyta: Lepicoleaceae) in tropical America

Species of Lepicolea are robust liverworts with main distribution in the Southern Hemisphere and on high mountains of tropical America and Asia. Three species have been recorded from tropical America, L. ochroleuca, L. pruinosa and L. ramentifissa. In the course of our research on neotropical liverworts we found that several collections of Lepicolea had been misidentified. Study of herbarium materials showed that the three species are morphologically well-defined although one of them, L. ramentifissa, had frequently been confused with L. pruinosa or L. ochroleuca. Lepicolea ramentifissa is probably restricted to Bolivia. Additionally to the characters mentioned in the literature, we found that the three species can be distinguished by the crenation of leaf margins and the shape of the basal cells of the lacinia. Lepicolea ramentifissa is identical to L. ochroleuca in leaf areolation and crenation of leaf margins, but clearly differs in having stem paraphyllia and numerous cilia and lacinia on leaf margins. SEM analysis revealed the occurrence of a continuous layer of thickening on the abaxial leaf surfaces in L. pruinosa and L. ochroleuca, and wax crystals on the adaxial leaf surface in L. pruinosa. This is the first observation of wax crystals in Lepicoleaceae.

Automated summary

This study investigates the identification issue of Lepicolea species and reveals morphological differences among these three species. Additionally, the occurrence of wax crystals in Lepicoleaceae is reported for the first time.