SEMs of Mesozoic ephippia of Daphnia from Khotont, Mongolia. a-c. Putative ephippium of Daphnia (Daphnia) from fragment 2046, its dorsal portion and reticulation. Note that the anterior half of the ephippium is deeper than the posterior half, giving a sub-triangular shape. d-f. Ephippium of Daphnia (Ctenodaphnia) from fragment 2018, reticulation and fine sculpture of valve. Red lines show the putative orientation of the egg axes. White scale bars: 0.1 mm for a, d; 0.01 mm for b-c, e-f.