No Morphometric Distinction between the Host Constrictotermes cyphergaster (Silvestri) (Isoptera: Termitidae, Nasutitermitinae) and its Obligatory Termitophile Corotoca melantho Schiødte (Coleoptera: Staphylinidae)

Abstract

Different species may live in termite nests, cohabiting in close association with the host colony or occupying nest cavities without direct contact with the host. The strategy of termitophile organisms to become integrated into termite societies include appeasement through chemical, morphological and/or behavioral mimicry. We investigated the hypothesis that there is a morphological mimicry between the obligate termitophile Corotoca melantho (Coleoptera: Staphylinidae) and workers of its termite host Constrictotermes cyphergaster (Isoptera: Termitidae). Pictures of thirty-one C. cyphergaster workers and C. melantho individuals were taken in top and side views and converted into thin-plate splines. Four homologous landmarks and five semilandmarks (reference points) were marked on the head and abdomen of both species and digitized. The body shape of both species are morphometrically similar, so there is no discrimination between specimens of termitophile beetles and worker of termite hosts. Body size of termite hosts is responsible for 20% to 30% of body shape variation, while the body size of termitophiles beetle affects near 50% to 60% body shape. However, termitophiles body shape had a greater variation than worker termites. This is the first study to compare morphological similarity among termites and termitophiles using morphometric geometry. Our results indicated the existence of a morphological mimicry between C. cyphergaster and C. melantho.