Bounded by crises: An overview of the evolution of marine ostracods during the Triassic

The Triassic was a turning in the history of biodiversity: bracketed by two major biotic crises, characterised biotic, climatic and tectonic events, it saw transition from Palaeozoic to Modern evolutionary faunas. Herein, we propose first synthetic analysis diversity marine brackish-water ostracods over entire Triassic, light palaeoecological, palaeoenvironmental palaeogeographical contexts. Although general trends witnessed poor ostracod communities during most Early after end-Permian crisis, roots their taxonomic rediversification were visible as early Dienerian. explosive diversification Spathian Anisian followed high-diversity plateau up brink end-Triassic extinction. A “morphological phylogeny” proposes that all Permian ornate Bairdiidae derived Petasobairdia Kungurian, with emergence Ceratobairdia-lineage Abrobairdia-lineage. While they are generally “poor cousin” trophic chain analyses, traces typical Mesozoic drilling predation on Late unexpectedly document increase efficiency predators abilities through Triassic. Finally, distribution very dynamic this interval, distinct peri-palaeo-tethyan peri-neotethyan biotas dispersal thus relative homogenisation onwards.