Stalking an insect metropolis: Natural history and evolution of the termite assassin bugs (Reduviidae:Salyavatinae)

Salyavatinae (Reduviidae; 108 spp. in 19 genera) are suspected to be specialist predators of termites due to limited observations for a paltry seven species in five genera. One species exhibits a unique “fishing” behavior using carcasses of recently-predated termites as a lure. Morphological analyses indicate that Salyavatinae may be paraphyletic; six species of Neotropical Sphaeridopinae, also hypothesized to feed on termites, may be the closest relatives of the only Neotropical genus of Salyavatinae. The first molecular phylogeny of Salyavatinae and Sphaeridopinae is here constructed using data from seven genetic loci from 28 species in nine genera and including representatives from each major clade of higher Reduviidae (60 taxa total). DNA was extracted from gut contents of 45 individuals of suspected-termite feeders and analyzed using PCR with termite-specific primers. Analysis of gut contents provides substantial supporting evidence for a specialist termite predator nature of this clade with records for 8 new spp. including two new genera and indicates some conservation of termite prey group among clades of termite assassins. Our molecular phylogeny corroborates the close relationship of the two termite-feeding subfamilies while better resolving the sister group to this clade. Enigmatic expanded structures on fore-tibiae of several genera of termite-specialist assassin bugs are present in a single clade. A BEAST dating analysis indicates colonization of the Neotropics by this primarily Old World clade is too recent to have occurred due to vicariance from continental drift.