15 spp.** in 4 genera* in our area; 234 described species in 8 genera worldwide (4 Oriental)(1)(2)(3)
*Genus not yet in the guide: Epirhyssa (1 sp.)
**Species not yet in the guide: E. dietrichi
(conspicuously yellow-marked: AZ)(4)
, Rhyssa hoferi
(reddish with white abdominal bands: CO, NM, AZ)(5)
, Rhyssella perfulva
(bright orange and yellow: FL)(6)
Ovipositors may exceed 200 mm(3)
Medium to large size, very long ovipositor, cylindrical abdomen becoming dorsolaterally compressed apically, hind coxae length more than twice their width. In all but 1 species in our area (Epirhyssa dietrichi), there's a small triangular areolet.
Rhyssinae are distinguished from all other ichneumonids, apart from Pseudorhyssa nigricornis
(Pimplinae: Delomeristini) by the strong ridges on the mesoscutum.
can be ruled out by the presence of anterolateral grooves on T2 of the abdomen not found in Rhyssinae and/or having the apex of T8 not terminating as a polished horn as in Rhyssinae.(7)
Some Pimplinae (esp. Ephialtini) are also superficially similar. Pimplinae can be ruled out as they lack the extent of transverse ridges on the mesoscutum found in Rhyssinae. Some Pimplinae also have more of a quadrate areolet, when present.
Worldwide except Australian(1)
; in the New World, the highest diversity occurs in the ne. hardwood forests, whilst in tropical countries there are only 2 genera(3)
Idiobiont ectoparasitoids of the immature wood-boring endopterygote insects, in our area usually larval woodwasps (Siricidae and Xiphydriidae), but may also develop as facultative hyperparasitoids using other woodwasp parasitoids as hosts or on virtually any endopterygote (some have even been cultured in the laboratory on entirely unnatural surrogate hosts)(3)