Adaptive strategies in populations of Chirocephalus diaphanus (Crustacea, Anostraca) from temporary waters in the Reatine Apennines (Central Italy)

Abstract

To investigate the relationship between the adaptive strategies of Chirocephalus diaphanus (Crustacea, Anostraca) and the environmental characteristics of its habitat, we studied two populations living in high-altitude biotopes with very different characteristics, i.e. a semipermanent pool (Tilia Lake) and a temporary one (Illica Plain Pool), and we examined the essential features of their biological cycles (growth rate, reproductive biology, sex ratio and life cycle). The results show that the two populations adjust to the biotopes in which they live, fully exploiting the brief period available for development, in agreement with hypotheses formulated in studies of other colonizers of temporary environments. The strategy adopted by the Chirocephalus diaphanus population of Tilia Lake, a predictable and relatively constant environment, is similar to the k type, characterized by slow growth, late reproduction and a long life cycle. In contrast, the Illica Plain population presents rapid growth, precocious reproduction and a short life cycle, since it is highly dependent on the precariousness and unpredictability of the pool in which it lives.