Fig. 2
From: Daphnia as a versatile model system in ecology and evolution
Three Daphnia species often used in biological research, representing three major clades of Daphnia within this large genus. a Newborn D. magna. b Adult D. magna. c Adult D. longispina. d Adult D. pulex. D. magna and D. pulex are predominately pond dwelling species, while D. longispina and related species are often found in large lakes. The three adult females carry parthenogenetic eggs (dark round objects) in their brood chambers. All animals are oriented with their head to the top and the ventral side to the right. The black round object in the head is the single complex eye. The large second antennae are used for swimming. All pictures by D. Ebert. Scale bar = 1 mm