Fossil mosses from the Early Cretaceous Catefica mesofossil flora, Portugal – a window into the Mesozoic history of Bryophytes

Abstract

A diverse assemblage of mosses from the Early Cretaceous Catefica mesofossil flora, Portugal, is described based on fragments of charcoalified and lignitized gametophytes and a single spore capsule. Nine different gametophyte morphologies are recognized and assigned to Sphagnopsida, Polytrichopsida and Bryopsida. None of the fossils can be included in any extant species. Four species have character combinations not known in any extant genera and are accommodated in three new genera as Chlorosphagnum cateficense gen. et sp. nov. (Sphagnales, family incertae sedis), Physcidium tortuosum gen. et sp. nov. and Physcidium simsimiae sp. nov. (Diphysciales, Diphysciaceae), and Canaliculidium fissuratum gen. et sp. nov. (Dicranales, Leucobryaceae). Three other species can be assigned to extant genera and are described here as Polytrichastrum incurvum sp. nov. (Polytrichales, Polytrichaceae), Dicranodontium minutum sp. nov. and Campylopus lusitanicus sp. nov. (both Dicranales, Leucobryaceae). One additional specimen has features suggesting affinity with Leucobryaceae but lacks characters critical for a definite generic placement. A single spore capsule is unassigned but is similar to capsules of members of the Ditrichaceae (Dicranales). All the fossil mosses recognised in the Catefica mesofossil flora are assigned to orders of extant mosses that diverged prior to the diversification of the Bryidae, the most diverse clade of living mosses. Based on extrapolations from their nearest living relatives, the Catefica mosses likely grew in more or less open environments, and in moist or wet sites that were primarily of low pH and low nutrient status.

Key words

Almargem Formation, Bryophyta, Early Cretaceous, fossil mosses, mesofossils, SRXTM, synchrotron radiation X-ray tomographic microscopy

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