Presence of uradenia in male adults of the genus Dismegistus (Hemiptera: Heteroptera: Parastrachiidae)

Abstract: Uradenia, often referred to as paragenital glands, are usually voluminous paired exocrine glands located ventrally in the abdomen mostly on the intersegmental membrane between abdominal segments (= urites) VII–VIII or VIII–IX, depending on sex or the taxon. They have been previously recorded from eight pentatomomorphan families belonging to Coreoidea, Lygaeoidea and Pyrrhocoroidea (Hemiptera: Heteroptera), found either in males, females or both sexes, and were thought to be absent in Pentatomoidea. We report here the first instance of uradenia in a pentatomoid genus, the African Dismegistus Amyot & Serville, 1843 (Parastrachiidae). Only the male adult possesses uradenia located on the intersegmental membrane of segments VIII–IX. The only other genus of the family, Parastrachia Distant, 1883, as well as other examined genera belonging to pentatomoid families possibly related to Parastrachiidae (Cydnidae, Thyreocoridae), do not possess uradenia. The uradenia of Dismegistus exhibit the same fundamental structure as in other trichophoran families but differ by their dorso-lateral position (instead of ventral), and also by the paired orifices (instead of unpaired and median). The implications of the presence of uradenia within member of a pentatomoid genus are briefly discussed.

Key words: Hemiptera, Heteroptera, Pentatomoidea, Parastrachiidae, Dismegistus, Parastrachia, morphology, abdominal segment VIII, ectodermal gland, uradenia