Diversity, environments, and biogeography of Homoloida (Decapoda: Brachyura) from the Late Jurassic to the present

ABSTRACT The section Homoloida with the sole superfamily Homoloidea comprises both extinct and extant brachyuran crab taxa, with records ranging from the Tithonian (Jurassic) to the present. Examination of fossil and modern occurrence records for this clade provides insight into the biogeography, biodiversity, and environmental preference of the homoloid crabs over time. The fossil record of Homoloidea, comprised of the families Tithonohomolidae, Mithracitidae, Homolidae, Latreilliidae, and Poupiniidae, is global in distribution and peaks in diversity during the uppermost Cretaceous with the most recent fossils known from the Miocene. Modern homoloids are absent from only a handful of regions globally, with particularly high diversity and abundance in the tropical Indo-West Pacific. Comparison of interpreted depositional environments for fossil occurrences and depth records for modern occurrences sheds light on the environmental preferences and potential spatial sampling biases of this clade. By assessing both fossil and modern records of Homoloidea, patterns (e.g., absence from cold-water latitudes, Oligo-Miocene disappearance from the northeastern Pacific) emerge that may have important implications for future study of this clade, particularly in relation to dispersal/turnover events and environmental constraints.