Feeding Site Specificity in Frog-biting Midges (Corethrellidae)

Abstract

Hematophagous arthropods often choose predictable feeding sites on their hosts´ body, presumably to maximize blood uptake while minimizing costs. Feeding sites can be host-specific, mediated by intrinsic host characters and/or specific preferences of the blood feeder. We investigated feeding site specificity in a community of frog-biting midges (Corethrella spp.) and frog hosts in La Gamba, Costa Rica. Midge distribution on hosts differed significantly between 12 investigated frog species, indicating that intrinsic host properties influence potential feeding sites. However, realized feeding sites were also significantly different between four investigated Corethrella morphotypes, across all hosts but also within certain shared hosts, indicating feeding site partitioning among Corethrella. We propose that the diversity of feeding sites in Corethrella-frog associations is determined by an interaction of host traits, e. g. calling site, defensive behavior or skin thickness, and midge traits, especially body size and corresponding mouthpart size/structure.