Key to the Neotropical species of Gnathochorisis (females) 1. Face fuscous.........................................................................................2 - Face yellow or yellowish-rufous........................................................................ 5 2. Head 1.1 × as wide as high. Face narrow and coriaceous, at the level of antennal fossae 0.35–0.38 × as wide as head (Fig. 4 A), metasomal tergites 2–4 more or less uniformly colored....................................... G. austrinus Dasch - Head at least 1.2 × as wide as high. Face not so narrow, at the level of antennal fossae at least 0.4 × as wide as head; metasomal tergites 2 and 3–4 of different contrast color (usually tergite 2 pale or yellowish, whereas tergites 3 and 4 mostly fuscous).. 3 3. Notauli deep; tips of fore wings dusky. Mesoscutum ferruginous, metapleuron black; second tergite yellowish-white, except apical black spot.................................................................... G. laticincta (Cresson) - Notauli shallow, indistinct; wings more or less evenly slightly infumate, without dark tips. Mesosoma evenly coloured. Second tergite pale, without apical black spot.................................................................... 4 4. Mesosoma fuscous, fore wing vein cu-a postfurcal; face 0.4 × as wide as head, finely coriaceous; hind femur 3.6 × as long as wide; area superomedia longer than wide. Second tergite pale with narrow fuscous apical edge, 0.6 × as long as wide posteriorly (Fig. 6 D)........................................................................ G. intercalaris sp. n. - Mesosoma rufous, fore wing vein cu-a interstitial; face 0.45 × as wide as head, coriaceous; hind femur inflated, 3.2 × as long as wide; area superomedia as long as wide; second tergite entirely pale, 0.75 × as long as wide posteriorly (Fig. 6 G)............................................................................................... G. rufithorax sp. n. 5. Frons and vertex fuscous (Figs 4 C, 5C); mesoscutum entirely fuscous; propodeal carinae reduced (Fig. 6 C); metapleuron slightly matt. Postpetiole and second tergite in basal 2/3 with longitudinal striae (Fig. 6 C). Hind coxae and femora fuscous dor- sally................................................................................... G. enodis sp. n. - Frons and vertex yellowish-rufous except fuscous interocellar area; mesoscutum entirely or partly rufous; propodeal carinae well developed. Postpetiole and second tergite without longitudinal striae (except punctata). Hind coxae and femora without fuscous marks dorsally................................................................................ 6 6. Scutellum and disk of mesoscutum along notauli and in the middle rufous; upper mesopleuron and metapleuron fuscous (Fig. 3 A).................................................................................. G. khalaimi sp. n. - Mesosoma mostly red or yellowish; mesopleuron and metapleuron entirely yellowish rufous........................ 7 7. Mesosoma entirely red; scutellum without lateral carinae; costulae and apophyses of propodeum well developed (Fig. 7 B); mandibles not sinuous, antennae not longer than body, subapical flagellomeres 1.5 × as long as wide......... G. rufa sp. n. - Mesosoma pale or yellowish red, scutellum with lateral carinae; costulae of propodeum reduced, area basalis and area superomedia fused, propodeum without strong apophyses (Figs 6 B, 6F); mandibles strongly tapered and sinuous (Fig. 4 I); antennae clearly longer than body, subapical flagellomeres more elongate, about 2.5 × as long as wide........................ 8 8. First tergite and second tergite in basal half with longitudinal striae; area superomedia 1.3 × as long as wide (Fig. 6 F). Mesoscutum reddish brown, metasoma mostly fuscous except third tergite latero-apically, lateral vague spots on tergites 4–5 and sixth tergite laterally; legs pale with distinct fuscous bands on hind coxae, femora and tibiae. Areolet narrowed apically....................................................................................... G. punctata sp. n. - Tergites 1–2 without striae; area superomedia 2.0 × as long as wide (Fig. 6 B). Mesoscutum yellowish-rufous, only flagellum, interocellar area, scutellum, postscutellum, first tergite, apical 2/3 of third tergite and fourth tergite fuscous; legs uniformly yellowish-rufous. Areolet parallel-sided.......................................................... G. dilleri sp. n.

Published as part of Humala, Andrei E., 2017, New species of the genus Gnathochorisis Förster (Hymenoptera: Ichneumonidae: Orthocentrinae) from the Neotropical Region, pp. 201-218 in Zootaxa 4250 (3) on pages 203-204, DOI: 10.11646/zootaxa.4250.3.1, http://zenodo.org/record/495011