Selective extinction at the end-Cretaceous and appearance of the modern Decapoda

Extinction and origination of genera and families of marine Decapoda at the end of the Cretaceous established the modern fauna. Podotrematous crabs suffered high extinction levels, whereas heterotrematous crabs experienced both extinction and radiation. Anomuran decapods exhibited high extinction levels at the generic but not family level. In general, family extinctions predominantly occurred among podotrematous and heterotrematous crabs, which also exhibit overall shorter family ranges. Possible refugia promoted survival of genera and families into the Paleocene, whereas habitation of the Western Interior Seaway ensured high levels of extinction. Areas proximal to the Chicxulub impact site experienced moderate levels of extinction. Habitat specialists preferentially survived the end-Cretaceous extinction in some clades. Heterotrematous crabs recovered rapidly in the Paleocene, especially in the siliciclastic environments of the Americas. Because decapod crustaceans are highly variable in morphology, habitat, and ecology, no one pattern of extinction and recovery can explain the end-Cretaceous decapod extinction event. Rather, a mosaic of responses in various decapod groups led to their differential survival.