Unravelling evolutionary relationships between epifoliar Meliolaceae and angiosperms

Epifoliar fungi are a group of poorly studied fungal symbionts that coinhabit the surface of living plants. Meliolaceae is the largest group of epifoliar fungi and has been considered as obligate parasites. We investigated the taxonomy of Meliolaceae and the coevolutionary events with their host plants using time-calibrated cophylogeny based on large subunit, small subunit, and internal transcribed spacer (ITS) sequence data obtained from 17 different fungal taxa andrbcL, ITS, andtrnH-psbAsequence data from their corresponding hosts. Nine new fungal species are introduced in this paper andAppendiculellais synonymized underAsteridiella. The dominant coevolutionary events during the Cretaceous and Cenozoic are cospeciation and host shift, respectively. We hypothesize that the evolutionary history of epifoliar fungi can be divided into three major periods: origins of families, formations of genera, and diversification of species. The rise of angiosperms prompted the evolution of modern epifoliar fungi and the diversification of orders of Angiospermae fostered the formation of epifoliar fungal genera. Phylogenetically, epifoliar fungal genera can be delimited according to their coevolutionary patterns and divergent periods.

Automated summary

This study investigated the taxonomy of epifoliar fungi Meliolaceae and their coevolutionary events with host plants. The dominant coevolution events were cospeciation and host shift during the Cretaceous and Cenozoic periods. The evolutionary history of epifoliar fungi can be divided into three major periods: origins of families, formations of genera, and diversification of species.