Aulacidae

Definition

A small, cosmopolitan family of parasitoid wasps (Hymenoptera: Evanioidea) comprising approximately 200 described species in two extant genera. Aulacids are specialized endoparasitoids of wood-boring insects, primarily targeting wood wasps (Xiphydriidae) and xylophagous beetles. Adults are distinguished from their close relatives, the Gasteruptiidae, by a more robust, sculptured thorax, less elongate body form, non-clubbed hind legs, and the shared evanioid trait of a metasoma attached high on the propodeum above the hind coxae; the first and second metasomal tergites are fused and the head is borne on a long pronotal 'neck'.

Etymology

Example

A female Aulacus sp. searches for xiphydriid wood wasp larvae in decaying hardwoods, using her long ovipositor to penetrate wood and deposit eggs directly into the host's tunnel.

Related Terms

• Evanioidea
• Gasteruptiidae
• Xiphydriidae
• endoparasitoid
• Xylophagous
• parasitoid wasp
• wood wasp

Usage Notes

Formerly treated as a subfamily of Aulacidae s.l., some classifications now separate the group containing Aulacidae ampliforma and A. progenitrix into Cynipidae; current usage favors restricting Aulacidae to the core parasitoid lineage. The family is morphologically intermediate between the slender, club-legged gasteruptiids and the compact, cockroach-egg-parasitizing evaniids. Field identification relies on the elevated petiole attachment and pronotal 'neck' rather than coloration, which is typically black or dark metallic.