EUSTOCHUS Haliday, 1833

(Figs 420–438)

Eustochus Haliday, 1833a: 268, 1833b: 349 . Type species: Mymar atripennis Curtis, 1832, by monotypy.

Diagnosis. Body length 640–1145 μm. Head, mesosoma, petiole dorsally, and coxae heavily sculptured with raised reticulations (Figs 420, 421–425, 427–430); antenna with clava 2-segmented and narrowed towards apex (Fig. 420); fore wing with 2 distal macrochaetae and marginal vein present between them, parastigma, marginal and stigmal veins together as long as submarginal vein (Fig. 420).

Discussion. Among the nine other Nearctic genera of the Polynema group ( Acmopolynema, Caraphractus, Cnecomymar, Kalopolynema, Mymar, Neomymar, Palaeoneura, Polynema, Stephanodes), Eustochus is the sister genus to Caraphractus . Together they form a distinct subgroup distinguished by their heavily sculptured head, mesosoma, and petiole, at least dorsally.

Nearctic hosts. Unknown. An extralimital host is in Coleoptera (Pricop & Moglan 2016) .

Important reference. Huber & Baquero (2007).