Stethantyx cacaoensis 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 : 237-238

Stethantyx cacaoensis Khalaim et Broad , sp. nov.

( Fig. 56 )

Comparison. Very similar to S. sanjosea sp. nov., but differs from this species by the black frons and anterior part of vertex, thinner and sharper foveate groove of mesopleuron, and much longer ovipositor ( Fig. 56 ).

Description. Female. Body length about 4.65 mm. Fore wing length 3.35 mm.

Head strongly rounded behind eyes in dorsal view; temple almost half as long as eye width. Mandible with upper tooth distinctly longer than lower tooth. Clypeus broad, lenticular, flat in lateral view, mostly smooth, finely punctate on its upper half. Malar space about 0.6× as long as basal width of mandible. Flagellum of antenna with 25–26 flagellomeres (25 flagellomeres in holotype); subbasal flagellomeres about 1.7× as long as broad, subapical flagellomeres slightly elongate to subsquare. Inner eye orbits very weakly convergent ventrally. Face weakly prominent centrally. Face, frons, vertex and temple granulate, dull, without distinct punctures.

Notaulus vestigial in holotype (inconspicuous pit distant from anterolateral margin of mesoscutum) and absent in paratype. Mesoscutum finely granulate, finely and densely punctate. Scutellum with lateral longitudinal carinae extending from its base to 0.3–0.4 of length of scutellum. Foveate groove of mesopleuron situated in its anterior half, strongly oblique, narrow and rather short, sharp and crenulate, its anterior end far from anterior margin of mesopleuron. Mesopleuron finely granulate and finely punctate. Propodeum granulate, dorsolateral area finely and densely punctate (punctures mostly indistinct because of granulation), without wrinkles adjacent to carinae. Basal area of propodeum long and narrow, distinctly widened anteriorly, about 3.0× as long as broad and 0.45× as long as apical area; basal longitudinal carinae complete. Propodeal spiracle separated from pleural carina by less than 1.0× diameter of spiracle. Apical area flat, anteriorly pointed.

Fore wing with veins Rs +2 r and Rs angled about 110°. Vein 2 rs-m 1.5× as long as abscissa of M between 2 rsm and 2 m-cu. Hind wing with cu 1& cu-a vertical. Hind femur 6.0× as long as broad, 0.87× as long as tibia.

First tergite slender, 5.2× as long as posteriorly broad, mostly smooth, with petiole dorsoposteriorly and laterally finely striate. Glymma situated in apical 0.6 of tergite 1, small, joining by shallow furrow to ventral part of postpetiole (furrow is hardly discernible in paratype). Second tergite 2.5× as long as anteriorly broad. Thyridial depression more than 4.0× as long as broad. Ovipositor weakly upcurved, with shallow dorsal subapical depression; sheath 3.1× as long as first tergite and 2.8× as long as hind tibia.

Head predominantly yellowish orange; frons (except lower eye orbits) and anterior part of vertex blackish; face, clypeus, malar space, palpi and mandible (teeth reddish) yellowish. Antenna black, scape and pedicel ventrally dark brown. Mesosoma yellowish orange; mesoscutum with longitudinal median blackish mark in holotype and black centrally in paratype; propodeum dorsally infuscate. Tegula fuscous. Pterostigma brownish black. Legs yellowish, hind tibia and tarsus infuscate. Metasomal segment 1 brown. Metasoma behind tergite 1 predominantly brownish yellow, tergite 2 dorsally dark brown with narrow yellowish band posteriorly, tergite 3 dorsoanteriorly brown.

Male. Unknown.

Variation. The paratype is almost identical with the holotype with minor variation in coloration. It is slightly darker than the holotype with the mesosoma predominantly reddish orange, first metasomal segment dark brown and tergites 2 and 3 brownish black.

Etymology. Named after the Cacao volcano in the Guanacaste National Park of Costa Rica, where a large number of Tersilochinae specimens were collected.

Material examined. Holotype female (BMNH), San José Prov., Zurquí de Moravia, on edge of Braulio Carrillo National Park, 1600 m, X–XII.1990, coll. I.D. Gauld.

Paratype. Guanacaste Prov.: 1 Ƥ (INBio) Guanacaste National Park, SE of volcano Cacao, Estación Cacao, 1000–1400 m, VIII.1991, coll. D.G. García.

Distribution. Costa Rica (Guanacaste, San José).

Figures

FIGURES 56 – 59. Stethantyx cacaoensis sp. nov., Ƥ: 56 — habitus, left (holotype). Stethantyx cartagoa sp. nov., Ƥ: 57 — antenna, left. Stethantyx mesoscutator sp. nov., 3: 58 — head and mesosoma, left; 59 — propodeum and base of metasoma, dorsolateral.