Stethantyx curvator 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 : 240-241

Stethantyx curvator Khalaim et Broad , sp. nov.

( Fig. 2 , 30 )

Comparison. Similar to S. altamira sp. nov. as both have a basally slender flagellum ( Fig. 16 ) and a long and apically sinuous ovipositor ( Fig. 31 ). Differs from S. altamira by the evenly granulate, dull and very finely punctate mesopleuron and dorsolateral area of the propodeum (in S. altamira the mesopleuron and dorsolateral area of propodeum are more or less smooth, mesopleuron also distinctly punctate); weaker foveate groove of the mesopleuron; propodeum with the basal area (basal longitudinal carinae often indistinct anteriorly) ( Fig. 30 ); and a somewhat longer ovipositor with the lower valve subapically deeper and the dorsal notch more sharply defined.

Description. Female. Body length about 4.9 mm. Fore wing length 3.4 mm.

Head roundly narrowed behind eyes in dorsal view; temple 0.41× as long as eye width. Mandible weakly narrowed towards apex, upper tooth somewhat longer than lower tooth. Clypeus lenticular, flat in lateral view, smooth and impunctate on lower half, finely granulate and rather densely punctate on upper half. Malar space 0.75× as long as basal width of mandible. Flagellum of antenna basally slender, distinctly clavate in holotype and filiform in one paratype, with 22–23 flagellomeres (22 flagellomeres in holotype); second flagellomere 1.9–2.5× as long as broad, mid flagellomeres distinctly elongate, subapical flagellomere transverse in holotype, distinctly elongate in paratype. Inner eye orbits very weakly convergent ventrally. Face weakly prominent centrally. Face and frons densely granulate and indistinctly punctate. Vertex and temple densely granulate, impunctate.

Mesosoma entirely and evenly granulate, with fine and usually indistinct punctures laterally on mesoscutum, and centrally on mesopleuron. Notaulus absent or as a very small tubercle distant from anterolateral margin of mesoscutum. Scutellum with lateral longitudinal carinae short, developed only in its anterior c. 0.3. Foveate groove of mesopleuron rather weak in holotype, moderately deep and narrow in paratypes, oblique, with fine transverse wrinkles, not reaching anterior margin of mesopleuron. Basal area of propodeum narrow, about 3.5× as long as broad, and 0.65× as long as apical area ( Fig. 30 ); basal longitudinal carinae subparallel or weakly divergent anteriorly, usually indistinct anteriorly ( Fig. 30 ). Propodeal spiracle separated from pleural carina by ≤ 0.5× diameter of spiracle. Apical area flat, anteriorly rounded ( Fig. 30 ).

Fore wing ( Fig. 2 ) with veins Rs +2 r and Rs angled about 100°. Vein 2 rs-m almost as long as abscissa of M between 2 rs-m and 2 m-cu, both these veins rather short. Hind wing with cu 1& cu-a subvertical. Hind femur 5.2× as long as broad, 0.87× as long as tibia.

First tergite 4.0× as long as posteriorly broad, dorsally coriaceous and dull except for smooth base and apex, petiole laterally striate. Glymma situated near middle of tergite 1, small, 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 about as long as body, upcurved, apically sinuous, dorsal notch well-defined, lower valve deeper subapically.

Head and metasomal segment 1 black; lower half of clypeus, palpi and mandible (teeth reddish) brownish yellow. Antenna brownish basally to fuscous apically. Mesosoma (including tegula) brownish orange. Fore and mid legs brownish yellow, coxae and trochanters yellowish. Hind leg brownish orange, femur and tibia brown to fuscous. Pterostigma blackish. Metasoma behind first tergite predominantly dark brown to black, hind margins of tergites dorsally pale.

Male. Unknown.

Variation. One paratype with fore wing with veins Rs +2 r and Rs angled 90°, and vein 2 rs-m thickened and distinctly shorter than abscissa of M between 2 rs-m and 2 m-cu.

Etymology. From the Latin curvatus (curved, bent) on account of its sinuous ovipositor apex.

Material examined. Holotype female (BMNH), Heredia Prov., Braulio Carrillo National Park, 9.5 km E of El Tunel, 1000 m, X–XI.1989, coll. I.D. Gauld.

Paratypes. Alajuela Prov.: 1 Ƥ (INBio) National Park Volcán Tenorio, N of volcano Tenorio, Guatuso, 1500– 1600 m, V–VII.2005, coll. J.A. Azofeifa. Heredia Prov.: 1 Ƥ (BMNH) 16 km SSE of La Virgen, 1050–1150 m, IV.2001.

Distribution. Costa Rica ( Alajuela , Heredia ).

Figures

FIGURES 1 – 6. Wings of Stethantyx spp., Ƥ: 1 — S. ajajuela sp. nov.; 2 — S. curvator sp. nov.; 3 — S. guanacasteca sp. nov.; 4 — S. heredia sp. nov.; 5 — S. niger sp. nov.; 6 — S. notaulator sp. nov.

FIGURES 30 – 35. Stethantyx curvator sp. nov., Ƥ: 30 — propodeum, dorsal. Stethantyx altamira sp. nov., Ƥ: 31 — ovipositor, left. Stethantyx guanacasteca sp. nov., Ƥ: 32 — mesosoma, left; 33 — propodeum, dorsal. Stethantyx heredia sp. nov., Ƥ: 34 — mesosoma, left; 35 — mesoscutum and scutellum, dorsal. Scale bars = 0.1 mm.

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.