Morphology and ontogeny of Cretaceous ostracods with preserved appendages from Brazil

The Lower Cretaceous ostracod Pattersoncypris micropapillosa Bate is redescribed, and Reconcavona sp. indet. with appendages preserved is described for the first time. The morphology of the carapace and especially of the appendages of P. micropapillosa is compared in detail with that of the Recent Cyprididae Eucypris virens , which demonstrates that there are substantial similarities. In addition to the adults of P. micropapillosa , a number of juveniles have also been recovered and described, and these are compared with the juveniles of E. virens . The ontogenetic development of P. micropapillosa is shown to be very similar to that of Recent Cyprididae. This has highlighted that this group of ostracods has changed very little over the last 100 My. P. micropapillosa is tentatively placed in the subfamily Cyprinotinae, based on features of the upper lip. As the morphology of the appendages and the ontogeny of P. micropapillosa are very similar to those of Recent forms, it is postulated that the function of the limbs and lifestyle were also similar, i.e. it was nektobenthic and an opportunistic detritus feeder.