A fossil species of Ceratolejeunea (Lejeuneaceae, Porellales) preserved in Miocene Mexican amber

A sterile liverwort inclusion in a piece of Miocene Mexican amber is described and assigned to the extant genus Ceratolejeunea. The inclusion has entire leaves with a basal group of 2-4(-ca. 7) ocelli, rather thin-walled leaf cells, large ovoid lobules and bifid, suborbicular underleaves. This combination of characters does not fit the morphology of extant species. Accordingly, the fossil is described as Ceratolejeunea antiqua, sp. nov., making it the second liverwort species known from Mexican amber.