Species have between 30 and 50 antennal segments, usually 36. Mandibles are bi-dentate. All have a dorsal spot on the scutellum, yellow to red in colour, though a few extra-generic species share this trait. They all have the basic Ichneumonid body shape and wing venation, and range in size from 12mm to nearly 30mm. Males seem to be the more colourful sex in this genus, and usually exhibit more striking banding patterns (usualy yellow/orange and black) on the abdomen than the females, which tend to be uniform in colour (usually reddish). Females in this genus do not have the charismatically large ovipositor seen in some other genera of this family, such as Megarhyssa, and specimens may require examination under a hand lens or microscope to assign a sex. A good secondary character for sexing specimens missing the genetalia, or entire abdomen for that matter, is the presence of a single tibial spur on each of the prolegs of the females only. Both males and females of the genus have two tibial spurs on both the meso and metalegs. All have two tarsal claws at the end of each leg.
All Pterocormus species are parasititoids. Though most species in this genus have not been studied, those that have been tend to prefer Lepidopteran hosts, especially those of the families Cossidae, Hepialidae, Arctiidae, and Noctuidae.
Pterocormus species have been discovered on all continents except Antarctica. There are approximately fifty species in Canada and the United States.
|genus page author||Haughian, S.||2004 |