Eustochus, Haliday, 1833

Huber, John T., Read, Jennifer D. & Triapitsyn, Serguei V., 2020, Illustrated key to genera and catalogue of Mymaridae (Hymenoptera) in America north of Mexico, Zootaxa 4773 (3), pp. 1-411 : 174-178

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).

Figures

FIGURE 420. Eustochus sp., habitus. USA, California, Tuolumne Co., Stanislaus Nat. Forest, 5561’, 1 mi. N. hwy 108, 38°21'50"N 119°52'20"W, 12.vii.2006, S. Fullerton, E. Zoll, S. Kelly, P. Russell. Scale bar=500 μm.

FIGURES 421–426. Eustochus sp., probably atripennis (Curtis), heads (Japan). 421, anterior; 422, posterior; 423, lateral; 424, dorsal; 425, ventral; 426, mouthparts. Scale bars=50 μm.

FIGURES 427–433. Eustochus sp., probably atripennis (Curtis) (Japan). 427, mesosoma, dorsal; 428, mesosoma, lateral; 429, mesosoma, ventral; 430, mesosoma, anterior; 431, petiole dorsal; 432, petiole, ventral; 433, petiole, lateral. Scale bars: 427–430=50 μm; 431–433=20 μm.

FIGURES 434–438. Eustochus sp., probably atripennis (Curtis) (Japan). 434, metasoma, dorsal; 435, metasoma, lateral; 436, metasoma, ventral; 437, apex of gaster, dorsal; 438, apex of gaster, lateral. Scale bars: 434–436=100 μm; 437, 438=20 μm.