Gnathochorisis enodis Humala, sp. nov.

Figs 2 C, 4C, 5C, 6C.

Description. Female (holotype). Fore wing length 4.0 mm.

Head 1.15 × as wide as high; frons nearly polished with weak microsculpture; face polished, scarcely and finely punctate, densely covered by long whitish hairs, at the level of antennal fossae 0.45 × as wide as head (Fig. 4 C). Inner orbits slightly convergent ventrally. Clypeus separated from face, about 1.6 × as wide as high, apical edge of clypeus truncate; malar space 1.1 × as long as mandible basal width, with subocular sulcus; mandibles comparatively robust, with lower tooth shorter than upper tooth; maxillary palp reaching fore coxa. Occipital carina complete; temple 0.35 × as long as eye length, ocular-ocellar line 1.2 × as long as maximum diameter of lateral ocellus, postocellar line 0.8 × as long as maximum diameter of lateral ocellus (Fig. 5 C). Antenna moderately long, with 22 flagellomeres, basal flagellomere 5.3 × as long as wide, subapical flagellomeres about 1.5 × as long as wide.

Mesosoma 1.4 × as long as high. Mesoscutum matt with adpressed dense setae; epomia short, notaulus shallow; epicnemial carina complete; scutellum without lateral carinae. Propodeum nearly polished with long and sparse whitish pubescence; transverse and most of lateromedian longitudinal carina excluding apical portion reduced. Most of metapleuron nearly polished.

Fore wing with comparatively large petiolate areolet, longer than high, 2rs-m as long as 3rs-m; vein cu-a inclivous, opposite Rs+M; hind wing with nervellus intercepted at lower 0.4, Cu1 present. Hind leg stout, coxae and femora polished, tibiae and tarsi coriaceous, hind femur inflated, 3.6 × as long as high. Hind tibia 6.4 × as long as its maximal width subapically; basitarsus 0.45 × as long as hind tibia.

First metasomal segment slender, moderately arched, 2.8 × as long as posteriorly broad, dorsal longitudinal carinae weakly developed; postpetiole longitudinally striate. Spiracle at 0.45, sternite at 0.5 of first tergite length. Second tergite 1.1 × as long as posteriorly wide, with longitudinal thyridium in basolateral corners and longitudinal striae, in apical 1/4 smooth (Fig. 6 C). Remaining tergites of metasoma polished, somewhat compressed laterally from tergite 4. Ovipositor upcurved, about as long as first metasomal segment, with blunt subapical dorsal notch.

Fuscous. Face, including narrow areas around antennal fossae and excluding narrow fuscous orbits, clypeus, malar space, mandibles excluding tips, scape and pedicel ventrally, palps, tegula, subtegular ridge, base of wings, propleuron, pronotum except small dorsal area, lower mesopleuron, fore and mid coxae and trochanters whitishyellow; legs mostly light-brown, hind coxa and trochanter fuscous dorsally, hind femur with dorsal dark strip, all tarsi brown. Metasoma fuscous; second tergite with apical band and thyridium light brown, third tergite light brown basally and with narrow light apical band, remainder of metasoma brownish. Wings hyaline, veins and pterostigma brown.

Male. Unknown.

Comparison. This is the only known species of Gnathochorisis in the Neotropics with considerable reduction of propodeal carinae. It is similar to the Nearctic G. novaeangliae Dasch in this character, but differs in the presence of longitudinal striae on tergites 1–2; stouter mandibles; the yellow face, propleuron, pronotum and lower mesopleuron; the dorsal dark strip on the hind femur; and mostly rufous hind coxa.

Material examined. Holotype female (UNAM), México, Oaxaca, Santiago, Comaltepec, 2427 m, N 17.58424°, W 96.49428°; humid oak pine forest, Malaise trap 12–20.VI.2007, leg. H. Clebsch. Distribution. Mexico (Oaxaca) (Fig. 1).

Etymology. Named after the obliterated carinae of the propodeum.