The effect of temperature on morphology, life history and growth rate of Filinia terminalis (Plate) and Filinia cf. pejleri Hutchinson in culture

• 1 Experiments on the influence of temperature (5–25°C) on morphology, life history and growth rate of Filinia terminalis and F. cf. pejleri were performed in replicated individual cultures with Oocystis sp. as food.
• 2 Some morphological characteristics previously used for the identification of both species were found to be affected by temperature and also by life cycle stage. However, numbers of unci teeth were not affected.
• 3 Body and setal lengths, life spans, all stages of development, and growth rates of both species decreased with increasing temperature.
• 4 Offspring number per female of both rotifers was highest at 20°C. Maximum growth rate of F. terminalis was at 25°C, whereas that of F. cf. pejleri was at 20°C.