STETHYNIUM Enock, 1909

(Figs 979 –1010)

Stethynium Enock, 1909: 452 . Type species: Stethynium triclavatum Enock, 1909, by monotypy.

Diagnosis. Body length 525–715 μm. Clava 3-segmented, the sutures between segments strongly oblique (Fig. 984); mandible with 4 teeth (Fig. 1000); frenum longitudinally divided, with paramedial plate longer than wide; second phragma with rounded (convex) apex (Figs 985, 1001); fore wing with distinct rounded lobe behind venation (Fig. 987). Male with complex asymmetrical genitalia (Figs 993, 1010).

Discussion. Among the four other genera in the Nearctic with frenum longitudinally divided: Anagrus, Krokella, Platystethynium (Platypatasson) and Schizophragma, only Krokella also has a 3-segmented clava. Stethynium differs from it by the mandible normal, with 4 equal teeth in both sexes, fore wing more evenly rounded and with a distinct lobe behind apex of venation, and venation shorter.

Nearctic hosts. Unknown. Extralimital hosts are Hemiptera: Cicadellidae, including an important pest in vineyards, Empoasca vitis (Goethe) (Viggiani 2002) .

Important reference. Huber (1987).