We revise the large Neotropical genus Operclipygus Marseul, in the histerid tribe Exosternini (Histeridae: Histerinae). We synonymize 3 species, move 14 species from other genera, sink the genus Tribalister Horn into Operclipygus, and describe 138 species as new, bringing the total to 177 species of Operclipygus. Keys are provided for the identification of all species, and the majority of the species are illustrated by habitus and male genitalia illustrations. The species are diverse throughout tropical South and Central America, with only a few species extending into the temperate parts of North America. The majority of species can be recognized by the presence of a distinct stria or sulcus along the apical margin of the pygidium, though it is not exclusive to the genus. Natural history details for species of Operclipygus are scant, as most specimens have been collected through the use of passive flight interception traps. Many are probably generally associated with decaying vegetation and leaf litter, where they prey on small arthropods. But a small proportion are known inquilines, with social insects such as ants and termites, and also with some burrowing mammals, such as Ctenomys Blainville.
Caterino MS, Tishechkin AK (2013) A systematic revision of Operclipygus Marseul (Coleoptera, Histeridae, Exosternini). ZooKeys 271: 1–401. doi: 10.3897/zookeys.271.4062