Figure 2From: Mesozoic fossils (>145 Mya) suggest the antiquity of the subgenera of Daphniaand their coevolution with chaoborid predatorsSingle-egged ephippial females of Daphnia and Simocephalus. a-b. Daphnia (Ctenodaphnia) pusilla, general view of ephippial female and ephippium. c. Simocephalus exspinosus, ephippial female. d. Simocephalus vetulus, ephippium. Scales: 1 mm for a, c; 0.1 mm for b, d.Back to article page