Abstract: 8712 A. Introduction
Unlike other cladocerans, members of the genus Ceriodaphnia (family Daphniidae) lack a rostrum and tail spine. Ceriodaphnia are amenable to laboratory culture due to their smaller size and shorter generation time than Daphnia, their closely related and morphologically similar counterpart. Under optimal conditions, Ceriodaphnia produce 3, sometimes 4 broods within 1 week of hatching, while the larger Daphnia do not reproduce until the 4th to 6th instar stage after hatching.1,2
A life-cycle test using Ceriodaphnia was developed in the early 1980s3 and subsequently introduced for use in effluent and ambient water evaluation.4 Several methods have since been published.5–7