New crabs (Decapoda: Brachyura: Prosopidae) from Jurassic (Oxfordian) Sponge Bioherms of Dobrogea, Romania

A previously undescribed fauna of primitive brachyurans of the family Prosopidae is reported from sponge bioherms in eastern Romania. One new species, Cycloprosopon dobrogea, and several other forms, constitute the brachyuran fauna. The sponge bioherms, which attain a height of 30 meters, have yielded an abundant, but not overly diverse, array of benthic invertebrates. Some of the brachyuran specimens bear epibionts, unusual in the fossil record of the Decapoda. The constitution of several genera within the Prosopidae is herein summarized in order to facilitate further work on the family within the context of modern systematic methods.