An Early Cretaceous branchiopod community in northeastern China: Discovery of daphniid (Cladocera: Anmopoda) ephippia in the early assemblage of the Jehol Biota

Freshwater branchiopod communities exhibit morphological and ecological stasis with the remote past. Here, we describe a new freshwater branchiopod community from the Lower Cretaceous Dabeigou Formation near Weichang County, northern Hebei Province (China), representing an early assemblage of the famous Jehol Biota. This branchiopod community consists of notostracans, conchostracans and cladocerans. Our new discovery of cladoceran ephippia in this community is described and discussed. These Ceriodaphnia-like ephippia are saddle-shaped in outline, and each ephippium has one oval egg with its long axis parallel to dorsal margin. They represent the oldest known ephippia record from China. Our discovery broadens our knowledge about reconstruction of the early assemblage and palaeoecology of the Jehol Biota. (C) 2020 Elsevier Ltd. All rights reserved.