Aoplus Tischbein, 1874

Aoplus is a small genus with 15 Nearctic species that may be related to ,or at least superficially similar to Cratichneumon and Homotherus. All three are united by the oxypygous females, the granulate to smooth postpetiole, and the lack of a median tubercle on the anterior margin of the propodeum. Aoplus and Homotherus are separated from Cratichneumon by the wide gastrocoeli and thyridia, which are wider than the interthyridial width. Aoplus differs from Homotherus by the ventrally tapering head (roughly parallel-sided in Homotherus) , the granulate mesonotum (smooth in Homotherus), and the thyridia, which are oblique, similar to Stenichneumon. In practice, though, separating these two genera can be quite difficult.

Aoplus species are typically either predominantly brownish-red or black.

The majority of Neactic species have been described, but there may be a few undescribed species.

Diagnosis

• mesonotum granulate
• female metasomal apex oxypygous
• postpetiole usually granulate or infrequently smooth
• anterior margin of propodeum without median tubercle
• thyridia wider than interthyridial width and weakly to strongly oblique (as in Stenichneumon)