Morphology of the Reproductive and Alimentary Systems of the Aradoidea (Hemiptera), with Comments on Relationships within the Superfamily

Abstract

Reproductive and alimentary structures were studied in 24 species representing 14 genera of 5 subfamilies of Aradidae and in 1 species in 1 of the 2 known genera of Termitaphididae, and external female genitalia were studied in representatives of all 8 aradid subfamilies and in the termitaphidid species. Most Aradoidea were found to have a very primitive bulbus ejaculatorius with only 2 epithelial layers, corresponding to the middle and inner layers of the complex bulbus of other land bugs. In some Aradidae, however, the bulbus is 3-layered in its posterior region. Ovaries and testes were most frequently found to have 5 ovarioles and follicles, respectively, but the numbers of both ranged from 2 to 6. A small rectal diverticulum was found in Prosympiestinae, and a well-developed one in Carventinae and Mezirinae. On the basis of retention of several primitive features in the reproductive and alimentary organs, the Aradoidea are regarded as representing a very early offshoot in the evolution of terrestrial Heteroptera that became specialized for a sedentary and mycetophagous mode of life. The current classification of the superfamily Aradoidea (Usinger and Matsuda 1959. Classification of the Aradidae (Hemiptera-Heteroptera). British Museum (Natural History), London) is generally supported, but apparently the Carventinae and the Mezirinae should be combined into a single subfamily. The Termitaphididae do not seem sufficiently distinct from the various aradid subfamilies to warrant family status. The female ectodermal genital duct and the ovipositor of the various groups are compared and some generalizations concerning the latter are given.