Reproductive compatibility among populations and host-associated lineages of bed bugs, Cimex lectularius

Bed bugs offer a unique model for understanding host-associated divergence and incipient speciation in the urban environment.  This is due in large part to the small number of individuals needed to start a population and the paucity of potential host species within their environment.  Recently, several C. lectularius populations have been discovered throughout Europe that show host preferences for bats.  Often these bat associated populations can be found in human homes alongside other C. lectularius populations that are strictly associated with humans.  Additional populations have been found in United States poultry farms, appearing to show a preference for chickens.  At present, limited information exists on the reproductive compatibility among these different host-associated lineages.  To address this problem, we performed reproductive crosses of several different host-associated lineages of bed bugs including human, poultry, and bat associated.  To assess compatibility, the number of eggs produced and the number of eggs that hatched were recorded and compared between single mating pairs for 2 weeks.  All crosses performed displayed reproductive compatibility, with all hatch rates greater than 95%.  These results suggest that despite recent (poultry) and ancestral (bat) host radiations, bed bugs have not developed any pre- or post-zygotic mating barriers and the genetic differentiation of these populations is likely due to other mechanisms.