Synonyms and other taxonomic changes
Recent evidence suggests that the Ceropalinae is much more restricted than defined by Townes (1957)(Pitts et al., 2006). The genera Notocyphus and Minagenia either belongs in it's own subfamily (the former) or in the pepsinae (the latter). Currently the only other genus included in the subfamily Ceropalinae is extralimital to the nearctic (Irenangelus, neotropical).
Numbers
14 in the nearctic region. A few are polytypic.
Size
3-15 mm. Dimorphism with respect to size is not as marked in this genus as it is in many other pompilid genera.
Identification
Ceropalines (Ceropales is the only nearctic genus) are distinguished from other spider wasps by the following characters:
Hypopygium strongly compressed laterally or at least with the hypopygium possessing a strong longitudinal crease near the apex.
Labrum fully exposed.
Eyes strongly divergent above, emarginate above the middle.
Spines at apex of hind tibia of equal size and spacing.
None of the nearctic species have serrate hind tibia.
Lacks a groove in the second sternite and a pocket in the basioposterior corner of the third discal cell.
Range
Transcontinental. Some species are restricted, other are small and poorly known.
Habitat
Varied, related to host (see life cycle). Many species inhabit woods.
Season
Most of the warm season from May (early records from late April in Townes (1957)) to October.
Food
Adults often visit flowers. Spider prey varied (see Life Cycle).
Life Cycle
These wasps are cleptoparasites of other pompilidae. They lay an egg on the paralyzed spider prey of other spider wasps when the prey is left unattended during nest construction. The larva that hatches eats the host egg and then the spider. Some species may have several generations per year, probably host dependent.
Print References
Townes, H.K. 1957. Nearctic wasps of the subfamilies pepsinae and ceropalinae. U.S. Nat. Mus. Bull. 209: 1-286. (keys, descriptions, distribution)
Krombein, K.V. 1979. Pompilidae, pp. 1569-1570. In Krombein, K.V., P.D. Hurd, Jr., D.R. Smith, and B.D. Burks, eds. Catalog of Hymenoptera in America North of Mexico. Vol. 2 Apocrita (Aculeata). Smithsonian Inst. Press, Washington, D.C. (species, distribution, hosts of some species)
Pitts, J.P., M.S. Wasbauer, C.D. von Dohlen. 2006. Preliminary morphological analysis of relationships between the spider wasp subfamilies (Hymenoptera:Pompilidae): revisiting an old problem. Zoologica Scripta, 35:1 (pp.63-84).
