Ecomorphological Adaptations of Riparian Bembidiini species (Coleoptera: Carabidae)
There is a close relationship between body shape and ecology of the species of the tribe Bembidiini. Dorso-ventrally flattened species with parallel-sided elytra tend to be lithophilous, i e, they live under or between gravel and stones on banks and shores, whereas stout species with an oviform hindbody form hide among vegetation, under dead leaves or in crevices in the earth. Species occupying an intermediate position as regards morphology are either euryoecious or independent of cover (gravel/stones, vegetation etc). An examination of information given in taxonomic literature revealed that lithophilous beetle species, almost without exception, have a depressed and often parallel-sided body, suggesting that these features have strong adaptive value. There are indications that competition may have contributed to the evolution of the depressed body form of the lithophilous species.