Tricostate mosses and associated bryophilous fungi from the Early Cretaceous of Vancouver Island (Canada)

Tricostate mosses and associated bryophilous fungi from the early Two novel fossil mosses (Tricosta plicata gen. et sp. nov. and Krassiloviella limbelloides gen. et sp. nov.) and several fungal morphotypes associated with one of these mosses are described here based on anatomically preserved material from the Early Cretaceous (Valanginian-136 Ma) Apple Bay locality of Vancouver Island (Canada). The mosses provide additions to the extremely short list of anatomically preserved bryophytes currently described from the pre-Cenozoic and have tricostate leaves (i.e., bearing three leaf veins or costae per leaf), a trait only known in a few other Mesozoic fossil mosses. Although the sporophytes of Tricosta and Krassiloviella are unknown, the high level of anatomical detail preserved in these fossils allows for whole-plant reconstructions of the gametophytes and the recognition of a new family of pleurocarpous mosses, Tricostaceae fam. nov. The bryophyte-inhabiting (bryophilous) fungi, known exclusively in association with the gametophytes of T. plicata, are represented by of Vancouver Island (Canada) several distinct morphologies including: epiphyllous hyphae and appressoria, intracellular haustoria and cell aggregates, and endophytic perithecioid fruiting bodies embedded within shoot tips. This is the first occurrence of bryophilous fungi documented in the fossil record. Both the moss gametophytes and the bryophilous fungi are common throughout the Apple Bay material, yet inconspicuous. Their characterization holds promise for future studies of anatomically preserved material in terms of documenting past bryofloras and mycofloras, both of which are fascinating but little-studied components of paleo-ecosystems.