Barycnemis Förster, 1869

Type species: Porizon claviventris Gravenhorst, 1829 .

Barycnemis can be distinguished from other Costa Rican tersilochine genera by the combination of a long, thin and linear foveate groove on the mesopleuron, the propodeum with a small spiracle and basal furrow distinctly longer than the apical area, thickened femora and tibiae, the hind tibial spurs distinctly curved apically, and the first metasomal tergite with distinct glymmae. The single Costa Rican species possesses a slender, apically white flagellum. The genus is characterized by considerable sexual dimorphism with males more difficult to recognize than females, especially so for the highly specialized species.

Barycnemis is a medium-sized, predominantly Holarctic genus with about 35 described species. In the New World 13 species occur in the Nearctic region (Horstmann, 2010), and two species were described from Mexico (Khalaim, 2002). One species has been found in Costa Rica, described below.

In Europe two species are known as parasitoids of Byrrhys sp. ( Byrrhidae) (Horstmann 1981) and Bledius spectabilis Kraatz (Staphylinidae) (Wyatt & Foster 1989), and in the Nearctic region B. linearis Ashmead was reared from Pissodes sp. ( Curculionidae) (Viereck 1912). The few known hosts thus represent a variety of families, although perhaps a generalisation can be made that at least hosts of some of the more specialized Barycnemis species live in soil or similar crumbly substrates.