pulchella Sars, 1862

Kotov, Alexey A., Ibragimova, Aisylu G. & Neretina, Anna N., 2018, Identification of Ceriodaphnia Dana, 1853 (Crustacea: Cladocera) taxa from European Russia based on ephippial morphology, Zootaxa 4527 (1), pp. 105-123 : 115-118

Ceriodaphnia pulchella Sars, 1862

( Figs. 9–10)

Length about 0.35 mm, width about 0.7 of length. In lateral view, ephippium semicircular; dorsal margin straight; ventral margin regularly curved from postero-ventral to antero-ventral angle ( Figs. 9A, 10 A–C). Paired latero-dorsal ridges absent ( Figs. 9 B–C). A depression along dorsum separates two halves of ephippium well-visible; sculpture of dorsal plate without any wrinkles, with numerous low spots covered by minute tubercles ( Fig. 9D). Egg locule very slightly extends laterally, without any wrinkles, in general smooth ( Fig. 9C), but bearing minute tubercles sometimes organized into spots ( Fig. 9E), probably these spots make locule surface non-transparent under light microscope ( Figs. 10 D–D). Space between egg locule and dorsal margin with same sculpture. The rest of ephippium with obscure (under SEM) polygonal reticulation ( Fig. 9F) – external sign of air-spaces which are well-visible under light microscope ( Figs. 10 D–F); lines of reticulation with especially minute tubercles. Ephippium has a very narrow ventral rim with obscure reticulation, lacking any tubercles ( Figs. 9F, 10F).

Note that in our material the ephippia were unusually small as compared to previous descriptions ( Jaksch 1992).