Transantarctic disjunctions in Schistochilaceae (Marchantiophyta) explained by early extinction events, post-Gondwanan radiations and palaeoclimatic changes

• We examined origin and historical biogeography of transantarctic disjunct liverwort family Schistochilaceae.
• The Schistochilaceae is inferred to have originated in the Late Cretaceous around 100 Mya.
• New Zealand was an early centre of radiation by long distance dispersal.
• Antarctica is assumed to have played an important role in the evolution the family.
• The distribution and biogeographic history of the family is very similar to that of Nothofagaceae.

The liverworts are the first diverging land plant group with origins in the Ordovician. The family Schistochilaceae exhibits diverse morphology and widely disjunct geographic ranges within the Southern Hemisphere. The family has been presented as a classic example of Gondwanan biogeographic distribution, with extant species ranges resulting from vicariance events. In this study, we present results that elucidate the origin and diversification of Schistochilaceae. We conducted a comprehensive time-calibrated, molecular-based phylogenetic analysis and different approaches for ancestral range inference of the family. Schistochilaceae is inferred to have originated in the Late Cretaceous, in an ancestral area including southern South America, West Antarctica and New Zealand. Despite a family origin at c. 100 Ma, most of the diversification of Schistochilaceae occurred in New Zealand after the 80 Ma opening of the Tasman Sea that isolated New Zealand from the rest of Gondwana. Most dispersals were transoceanic. The northward migration of the Schistochilaceae is probably linked with the spread of temperate vascular plant forest ecosystems that have Late Cretaceous southern origins and have maintained suitable environments for the family throughout the Cenozoic. The distribution and biogeographic history of the family is very similar to that of Nothofagaceae.

Figure optionsDownload as PowerPoint slide