2026/07/01 by David Horcajada‐Tejero, Candela Blanco‐Moreno, Hugo Martín‐Abad
paper · doi:10.1111/pala.70078
Abstract Examining the liverwort fossil collection from the Las Hoyas site, which was previously classified as Thallites sp., led to the discovery of a new species of Metzgeriales: Metzgeriites gynothallicus . This species is characterized by the presence of both asexual (propagule branches) and sexual (female branches bearing sporophytes) reproductive structures. A traditional morphometric study of its architecture reveals an absence of modular hierarchy, as well as two types of growth habit, termed here the ordered and unordered models. These models could correspond to two growth forms: the thalloid mat and the dendroid form. Regarding the habitats they colonized, taphonomic evidence and association analyses discarded an epiphytic habitat and suggest a saxicolous condition, although a saproxylic condition could not be disregarded. Metzgeriites gynothallicus is the first fossil example of a liverwort exhibiting two growth forms and is potentially the first Metzgeriales species to feature reproductive structures.