Synopsis of the species of Cheilolejeunea (Marchantiophyta, Lejeuneaceae) in the Pacific dominion and P?ramo province of tropical America

Cheilolejeunea is the third largest genus of the family Lejeuneaceae (Marchantiophyta) comprising approximately 130 species described globally; approximately 55 have been recorded for the Neotropics. We present here a synopsis of 31 species and four varieties of Cheilolejeunea that occur in the Pacific dominion and Paramo province of tropical America, representing 56% of the Neotropical diversity and ca. 19% of the global diversity of the genus. Most taxa (30 species and four varieties) occur in the Pacific dominion, with Cheilolejeunea schiavoneana being endemic to this dominion; Cheilolejeunea erostrata is endemic to the Paramo province, that registers 10 species and one variety. The highest diversity (26 taxa) is in the Magdalena province. In terms of ecology, Cheilolejeunea is most speciose in the lower montane rainforest (700-2400 m), with 77% of taxa (27) occurring in this ecosystem. We consider Cheilolejeunea erostrata to be Critically Endangered (CR-B1a). The synopsis of the genus includes descriptions of the species, notes on their distributions and habitats, illustrations, and an identification key.