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Vanhorniidae = Link 1
Description & Statistics
Vanhorniidae. -- There is a single North American species, Vanhornia eucnemidarum Crawford, which is a parasitoid of the larvae of eucnemid beetles.
The mandibles in this family are exodont, antennae are inserted just above the clypeus and the body is about 6.2 mm long (Masner 1993). The metasoma has almost all of its segments fused to form a large sheath. The ovipositor is contained in a ventral groove on the metasoma, with its apex pointing anteriorly.
Vanhornia eucnemidarum Crawford is a parasitoid of the larvae of Eucnemidae (Coleoptera) in mature maple trees (Acer spp.). The family has one genus with about 6 species reported by 1993 (Masner 1993).
The support of the metasoma was discussed by Mason (1983). He & Chu (1990) described one species from China, and Deyrup (1985) gave details of the biology of V. eucnemidarum.
The family was represented by only one North American genus and species, Vanhornia cucnemidarum Cwf. in 1940 (Clausen 1940/1962). The parasitoid was reared from the cells of larvae of the Coleoptera family Eucnemidae in decaying wood (Crawford 1909). At that time no biological studies were made.
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Crawford, A. W. 1909. A new family of parasitic Hymenoptera (Vanhorniidae). Proc. Wash. Ent. Soc. 11: 63-4.
Hedquist, K.L. 1976. Vanhornia leileri n.sp. from central Sweden (Hymenoptera: Proctotrupoidea, Vanhorniidae). Entomologica Scandinavica 7: 315-316.