The effect of temperature on the development of egg, naupliar and copepodite stages of two species of copepods, Cyclops vicinus uljanin and Eudiaptomus gracilis sars.

The duration times of the eggs, nauplii and copepodites of Cyclops vicinus and Eudiaptomus gracilis were obtained, by experiment, at 5, 10, 15 and 20°C. In contrast with previously published work on copepod development, the ovigerous females, used in the cultures at these temperatures, were removed from a water storage reservoir when it was at, or close to the experimental temperature.The results have been compared with those of other workers for the same species. The duration curves for the nauplii and copepodites of Cyclops vicinus were markedly different. The patterns of these differences and a plateau in the rate of development of copepodites at higher temperatures, suggest the Cyclops vicinus is able to acclimate or compensate for temperature changes. Its rate of development at lower temperatures, therefore, is faster than has previously been indicated by the literature. The results for Eudiaptomus gracilis are similar to those of other workers and show that its embryonic and post-embryonic development are strongly temperature dependent.