Clam shrimp Nothocarapacestheria from the Lower Jurassic of the Junggar Basin, northwestern China

Abstract

Abstract Nothocarapacestheria Rohn et al. , 2014 was erected based on material from the Upper Triassic–Lower Jurassic of the Paraná Basin, Brazil. Here we describe a Nothocarapacestheria species that has been discovered in the Lower Jurassic Badaowan Formation in Xinjiang, northwestern China. The described species is characterized by: (1) almost the whole carapace being ornamented with medium reticulations, 3–6 polygons per growth band, 20–60 µm mesh diameter; (2) the gradual transition to radially elongated reticulations in the distal region of the carapace, sometimes ending as radial lirae; and (3) fine puncta in the mesh of reticulations. Through this study, we are able to infer that the distribution of Nothocarapacestheria was more widespread than previously thought, and that Euestheria sp. previously reported from the Lower Jurassic Badaowan Formation are probably poorly preserved or juvenile individuals of Nothocarapacestheria .