Gene Exchange in a Ground Cricket Hybrid Zone

Abstract

The ground crickets Allonemobius fasciatus and A. socius (Orthoptera: Gryllidae) are sister species that form a mosaic hybrid zone in the eastern United States. The genetic structure of the hybrid zone has been studied extensively by the use of protein electrophoresis. Here, we report the discovery of several random amplification of polymorphic DNA (RAPD) markers that distinguish the two species, and we assess the congruence of RAPD markers and protein markers with regard to the identification of hybrids in mixed populations. Both sets of markers indicate that gene flow between A. fasciatus and A. socius is quite limited.