Specific manifestations of polyvariant life cycles in ground beetles (Coleoptera and Carabidae) along a latitudinal gradient

Abstract

The life cycles of Carabidae are highly diverse, and 25 variants of these cycles are realized In the European part of Russia, from semideserts to continental tundras. The diversity of the life cycle spectrum sharply decreases (by more than half) upon transition from nemoral to boreal forest communities, and its phenological unification takes place at high latitudes. The greatest proportion of species with polyvariant development (25%) is characteristic of temporal latitudes, which may be explained by relatively long growing season and considerable cenotic diversity. In both southern (semidesert and steppe) and northern regions (middle and northern boreal forests), this proportion does not exceed 5%. At low latitudes, the polyvariant pattern of development is often manifested in the form of facultative bivoltine life cycles or as facultative biennial life cycles in species with the initial "spring" breeding type.