Usually black spotted or banded with yellow, eyes deeply notched. Short legs. Differ from Myzininae (Tiphiidae) in being smaller and in lacking mesosternal lobes. Differ from Mutillidae in having the body bare.
Larvae are parasites or cleptoparasites of other aculeate larvae, esp. of leaf-cutting bees that nest in hollow twigs(1)
Widely distributed group; rather uncommon.