Origin, early evolution and palaeoecology of Gymnopleura (Crustacea, Decapoda): Basal palaeocorystoid crabs from the Upper Jurassic–Lower Cretaceous of central Europe

Recent fieldwork has yielded new decapod crustacean material from Upper Jurassic–lowest Cretaceous bioclastic limestones at Kotouč quarry near Štramberk (Moravia, northeastern Czech Republic). Two specimens in this lot can be ascribed to the superfamily Palaeocorystoidea and represent oldest gymnopleuran crabs known date. A genus species, Moravacarcinus stramberkensis, are here erected assigned a subfamily, Moravacarcininae, accommodate basal necrocarcinid. Our re-examination of Late Jurassic primitive southern Germany resulted discovery another early member group, referred genus, Juranecrocarcinus, as J. angulosum (Wehner, 1988). These finds demonstrate that palaeocorystoids originated within shallow-water, reefal settings reef belt across central Europe. We hypothesise members necrocarcinid subfamilies (Paranecrocarcininae Moravacarcininae subfam. nov.), thus Gymnopleura, were derived dynomeniform ancestor which adapted became modified for burying mode life. Possible candidates are, instance, goniodromitid Cycloprosopon Lőrenthey, Lőrenthey Beurlen, 1929 longodromitid genera Longodromites Patrulius, 1959 Planoprosopon Schweitzer, Feldmann Lazăr, 2007. The evolutionary pathways palaeogeographical history Mesozoic gymnopleurans markedly influenced by planktonic revolution considerably enriched deeper-marine clastic sediments with nutrients onwards.