Stethantyx osa Khalaim et Broad

Khalaim, Andrey I. & Broad, Gavin R., 2013, Tersilochinae (Hymenoptera: Ichneumonidae) of Costa Rica, part 2. Genera Megalochus gen. nov. and Stethantyx Townes, Zootaxa 3693 (2), pp. 221-266 : 253-254

Stethantyx osa Khalaim et Broad , sp. nov.

( Figs 18 , 45 )

Comparison. Similar to S. pseudoosa sp. nov. in colour pattern and structure, but differs in that the flagellum is distinctly tapered towards its apex, with shorter subbasal flagellomeres; it has a stronger notaulus; longer lateral longitudinal carinae of the scutellum; a wider basal area of the propodeum; a greater distance between the propodeal spiracle and the pleural carina; and a somewhat shorter ovipositor.

Description. Female. Body length almost 5.5 mm. Fore wing length 3.2 mm.

Head strongly rounded behind eyes in dorsal view; temple 0.48× as long as eye width. Mandible slender, moderately narrowed basally, upper tooth distinctly longer than lower tooth. Clypeus broad, about 2.9× as broad as high, lenticular, slightly convex or flat in lateral view, smooth and impunctate on lower half, finely and sparsely punctate on upper part. Malar space 0.45× as long as basal width of mandible. Flagellum of antenna narrowed towards apex, with 24–26 flagellomeres (24 flagellomeres in holotype), all flagellomeres distinctly elongate, subapical flagellomeres sometimes subsquare. Inner eye orbits very weakly convergent ventrally. Face with weak central prominence. Face and frons finely granulate, dull, finely and densely punctate. Vertex and temple finely granulate, dull, with fine, often indistinct punctures.

Notaulus usually with weak wrinkle extending from anterolateral margin of mesoscutum, and short and weak furrow behind this wrinkle. Mesoscutum finely granulate, dull, very finely and densely punctate. Scutellum with lateral longitudinal carinae usually extending from its base nearly to posterior end, but often weak or indistinct in posterior 0.3, usually not joining posteriorly. Foveate groove of mesopleuron situated in anterior 0.6 of mesopleuron, oblique, rather deep, with strong wrinkles anteroventrally which usually reach anterior margin of mesopleuron. Mesopleuron finely and shallowly granulate, very finely (partly indistinctly) punctate. Propodeum finely granulate, dorsolateral area very finely (sometimes indistinctly) punctate, without wrinkles adjacent to carinae. Basal area of propodeum usually slightly widened anteriorly (sometimes basal longitudinal carinae more or less parallel), about twice as long as broad, and 0.64× as long as apical area. Propodeal spiracle separated from pleural carina by 1.5–2.0× diameter of spiracle. Apical area flat, anteriorly truncate.

Fore wing with veins Rs +2 r and Rs angled 100°. Vein 2 rs-m slightly longer than abscissa of M between 2 rs-m and 2 m-cu. Hind wing with cu 1& cu-a slightly inclivous to vertical. Hind femur 4.5× as long as broad, 0.87× as long as tibia.

First tergite slender, 4.2× as long as posteriorly broad, smooth, petiole laterally striate. Glymma situated near middle of tergite 1, joining by fine furrow to ventral part of postpetiole. Second tergite 2.3× as long as anteriorly broad. Thyridial depression more than 4.0× as long as broad. Ovipositor weakly upcurved, with shallow dorsal subapical depression; sheath 1.36× as long as first tergite and 1.4× as long as hind tibia.

Head black; clypeus yellow ( Fig. 18 ); palpi, mandible (teeth black), scape and pedicel of antenna whitish. Flagellum yellow-brown basally to fuscous apically. Mesosoma orange; propleuron, anterior margin of pronotum and tegula yellowish. Legs yellow, fore and mid coxae and trochanters white, hind tibia slightly infuscate. Pterostigma dark brown. Tergite 1 of metasoma brownish black. Metasoma behind tergite 1 predominantly yellow, anterior parts of tergites 2 and 3 (sometimes also tergites 4 and 5) dorsally marked with brown or dark brown.

Male. Similar to female.

Variation. Ovipositor sheath 1.2–1.4× as long as tergite 1. Basal area of propodeum 1.6–2.2× as long as broad.

Etymology. Named after the type locality, Osa [Peninsula].

Material examined. Holotype female (BMNH), Puntarenas Prov., Osa Peninsula, Golfo Dulce Forest Reserve, 5 km W of Piedras Blancas, 100 m, II.1991, coll. I.D. Gauld & K. Gaston.

Paratypes. Alajuela Prov.: 1 Ƥ (BMNH) Guanacaste National Park, Estación Pitilla, 680 m, XI.1988, coll. I.D. Gauld & P. Mitchell. 2 Ƥ (BMNH) Los Chiles, Aguas Zarcas, 600 m, in coffee, XI–XII.1989. 1 Ƥ (INBio) Caño Negro, Playuelas, 20 m, I.1994, coll. K.L. Martínez. Heredia Prov.: 2 Ƥ (BMNH) Chilamate, Selva Verde, 75 m, IX–X.1989, XII.1989 – III.1990, coll. I.D. Gauld. 2 Ƥ (MUCR) La Selva Biological Station, 3 km S of Puerto Viejo, 10º26ʹ N, 84º01ʹ W, 50–150 m, IX.1992, coll. P. Hanson & C. Godoy. Puntarenas Prov.: Osa Peninsula, Golfo Dulce Forest Reserve, 5 km W of Piedras Blancas, 100 m, coll. I.D. Gauld & K. Gaston: 1 Ƥ (BMNH) XI.1990, 3 Ƥ (BMNH) XII.1990, 1 Ƥ (ZISP) I.1991, 2 Ƥ (BMNH) VII.1991, 1 Ƥ (BMNH) XII.1991, 1 Ƥ (BMNH) II.1992, 1 Ƥ (BMNH) XII.1992. 1 Ƥ (BMNH) Osa Peninsula, Golfo Dulce Forest Reserve, 24 km W of Piedras Blancas, 200 m, coll. I.D. Gauld & K. Gaston. 1 Ƥ & 1 3 (1 3 INBio, 1 Ƥ ZISP) Osa Peninsula, Estación Esquinas, 200 m, IX.1993, coll. M. Segura.

Distribution. Costa Rica ( Alajuela , Heredia , Puntarenas).

Figures

FIGURES 16 – 19. Stethantyx altamira sp. nov., Ƥ: 16 — head with antennae, left. Stethantyx orosia sp. nov., Ƥ: 17 — head, frontal. Stethantyx osa sp. nov., Ƥ: 18 — lower part of head, frontal. Stethantyx pseudoorossia sp. nov., Ƥ: 19 — head, frontal.

FIGURES 40 – 46. Stethantyx niger sp. nov., Ƥ: 40 — apex of ovipositor, left. Stethantyx orosia sp. nov., Ƥ: 41 — head, frontal; 42 — mesoscutum and scutellum, dorsal; 43 — mesosoma, left; 44 — propodeum, dorsal. Stethantyx osa sp. nov., Ƥ: 45 — head, frontal. Stethantyx pseudoorosia sp. nov., Ƥ: 46 — head, frontal. Scale bars = 0.1 mm.