Summary• The Early Devonian Rhynie chert has been critical in documenting early land plant-fungal interactions. However, complex associations involving several fungi that enter into qualitatively different relationships with a single host plant and even interact with one another have not yet been detailed.• Here, we studied petrographic thin sections of the Rhynie chert plant Nothia aphylla.• Three fungal endophytes (co)occur in prostrate axes of this plant: narrow hyphae producing clusters of small spores; large spherical spores/zoosporangia; and wide aseptate hyphae that form intercellular vesicles in the cortex. Host responses on attack include bulging of infected rhizoids, formation of encasement layers around intracellular hyphae, and separation of infected from uninfected tissues by secondarily thickened cell walls.• A complex simultaneous interaction of N. aphylla with three endophytic fungi was discovered. The host responses indicate that some of the mechanisms causing host responses in extant plants were in place 400 million yr ago. Anatomical and life history features of N. aphylla suggest that this plant may have been particularly susceptible to colonization by fungi.
A rachis of the fossil filicalean fern Botryopteris antiqua containing abundant septate hyphae with clamp connections is preserved in a late Visean (Mississippian; *330 Ma) chert from Esnost (Autun Basin) in central France. Largely unbranched tubular hyphae pass from cell to cell, but may sometimes produce a branch from a clamp connection. Other clamp-bearing hyphae occur clustered in individual cells or small groups of adjacent host cells. These hyphae may be tubular, catenulate with numerous hyphal swellings, or they may display a combination of both. The Visean hyphae with clamp connections predate Palaeancistrus martinii, the heretofore oldest direct fossil evidence of Basidiomycota, by some 25 Ma.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.