Influence of modified Banta’s medium and pond water on the longevity, egg production and body size ofDaphnia similis Claus andDaphnia cephalata King (Crustacea: Cladocera) under laboratory conditions

Abstract

The longevity ofDaphnia similis Claus is more in pond water (57 days) than in modified Banta’s medium (38 days) and the preadult instar number varied from 3–5,Daphnia cephalata King, however shows no variation in longevity or preadult instar number when cultured in both the media. The rate of egg production of both the species were higher in modified Banta’s medium than in pond water. The differences in the mean number of eggs per instar ofDaphnia similis andDaphnia cephalata in two different culture media are statistically significant (P<0·005;Anova). The variation in growth at each instar forDaphnia similis under two different culture media are statistically significant (P<0·005;Anova) but forDaphnia cephalata it is not significant.