Faunal turnover and niche stability in marine Decapoda in the Phanerozoic

Abstract

Patterns of diversity and faunal turnover of major groups of decapod crustaceans throughout the Phanerozoic are analyzed based upon data from all known fossil species reported to date. Age, range, and habitat preference data were compiled for 3637 species arrayed in 1035 genera and 173 families. Grouped at the infraordinal level, Anomura, Gebiidea, and Axiidea consistently occupied specific, preferred environments throughout their geologic history. Achelata are known from a variety of siliciclastic environments until the Holocene when they are found in coral and other carbonate environments. Habitat preferences of dendrobranch and pleocyemate shrimp, with a low preservation potential, are difficult to evaluate because they are found almost exclusively in low energy siliciclastics and lithographic limestones, whose mode of origin is not clear. Clawed lobsters, the so-called podotreme or primitive crabs, and heterotreme crabs have historically occupied a wide range of habitats. However, the temporal pattern of diversity of these groups is one of faunal turnover on a scale of tens of millions of years. Clawed lobsters were the first of these groups to be most diverse, followed in the Late Jurassic and Cretaceous by the podotreme or primitive crabs. Heterotreme crabs appeared in the Early Cretaceous and dominate numerically in the Cenozoic. These patterns of habitat preference of broad groups of decapods suggest that the limits of distribution are controlled by the Bauplan of each group rather than by extrinsic factors.