Stethantyx orellana Khalaim & Sääksjärvi, 2013

Khalaim, Andrey I., Sääksjärvi, Ilari E. & Bordera, Santiago, 2013, Tersilochinae of Western Amazonia (Hymenoptera: Ichneumonidae). Genus Stethantyx Townes, part 1, Zootaxa 3741 (3), pp. 301-326 : 315-316

Stethantyx orellana Khalaim & Sääksjärvi , sp. nov.

( Figs 31–34 , 57 )

Comparison. Stethantyx orellana sp. nov. may easily be distinguished from all other species of the genus by its very slender second tergite of metasoma which is 3.4–3.7× as long as broad anteriorly (at most 3.0× in other species). This species is also characterized by the predominantly black head and mesosoma, broad elongate basal area of propodeum, and ovipositor sheath 1.6× as long as first tergite.

Description. Female. Body length 7.2 mm. Fore wing length 3.9 mm.

Head very strongly rounded behind eyes in dorsal view; temple 0.43–0.52× as long as eye width. Mandible with upper tooth much longer than lower tooth. Clypeus lenticular, weakly convex in lateral view, smooth in lower half, densely punctate in upper part. Malar space 0.4–0.55× as long as basal width of mandible. Antennal flagellum distinctly narrowed towards apex, with 24–26 flagellomeres (26 flagellomeres in holotype); all flagellomeres, except basal and apical ones, 1.1–1.3× as long as broad. Face very densely punctate, weakly shining between punctures, with elongate prominence centrally. Frons very densely punctate, finely granulate, dull. Vertex very finely granulate, dull, with fine and dense punctures. Temple finely and densely punctate, smooth and shining between punctures. Hypostomal carina absent.

Notaulus as strong wrinkle. Mesoscutum finely granulate and densely punctate. Scutellum finely granulate, punctate, with lateral longitudinal carinae strong, reaching its posterior end and joining posteriorly. Foveate groove of mesopleuron deep and broad, upcurved anteriorly, with coarse transverse wrinkles, extending from prepectal carina to almost hind end of mesopleuron (shorter in one small specimen). Mesopleuron distinctly punctate, smooth between punctures centrally and finely granulate peripherally. Propodeum granulate, dorsolateral area finely punctate. Transverse carina and apical longitudinal carinae with very short wrinkles adjacent to carinae. Basal area of propodeum very broad, rectangular, 1.5–1.9× (1.5× in holotype) as long as broad and half as long as apical area. Propodeal spiracle separated from pleural carina by 0.5–1.0× diameter of spiracle. Apical area long and narrow, almost twice as long as broad, truncate anteriorly, flat.

Fore wing with first and second sections of radius angled about 110°. Intercubitus distinctly longer than abscissa of cubitus between intercubitus and second recurrent vein. Metacarpus almost reaching apex of fore wing. Hind wing with nervellus vertical.

Legs slender. Hind femur clavate, 4.5× as long as broad, and 0.89× as long as tibia. Hind spurs weakly curved at apex.

First tergite very slender, 5.5× as long as posteriorly broad, smooth, with shallow groove before glymma in holotype and partly striate or coriaceous laterally in paratypes. Glymma situated somewhat behind middle of tergite, moderately large, not joining to ventral part of postpetiole. Second tergite 3.4–3.7× as long as anteriorly broad. Thyridial depression long, far distad anterior margin of second tergite. Ovipositor upcurved, with shallow dorsal subapical depression; sheath 1.6× as long as first tergite and almost twice as long as hind tibia.

Head black; clypeus yellow to brownish yellow with upper margin sometimes brown; palpi and mandible (teeth black) yellow. Antenna with scape and pedicel yellowish, flagellum fuscous. Mesosoma black, propleuron and anterior margin of pronotum brownish. Tegula yellow-brown to dark brown. Pterostigma brown. Legs yellow to brownish yellow; hind leg with coxa and apical 0.7 of femur brown, tibia fuscous except apex and tarsus infuscate basally. First metasomal tergite brownish black, following tergites yellow ventrally to brown dorsally.

Male. Unknown.

Variation. Mesosoma reddish brown to black, hind leg yellow to pale brown. Ovipositor sheath 1.3–1.6× as long as first tergite.

Etymology. Named after the type locality, Orellana province in Ecuador.

Material examined. Holotype female (USNM), Ecuador, Orellana Prov., Tiputini, 0º37′55′′ S, 76º08′39′′ W, 220–250 m, canopy fogging, 21.X.1998, coll. T.L. Erwin et al.

Paratypes. Ecuador, Orellana : 1 ♀ (ZMUT) same label as holotype, but 7.II.1999. 3 ♀ (ZMUT, ZISP, BMNH) Onkone Gare, 0º39′25.7′′ S, 76º27′10.8′′ W, 216.3 m, canopy fogging, 10.X.1994, 30.VI.1998, coll. T.L. Erwin et al.

Distribution. Ecuador ( Orellana ).

Figures

FIGURES 31 – 36. Stethantyx orellana sp. nov., ♀, holotype (31, 33, 34) and paratype (32): 31 — head, frontal; 32 — head, mesosoma and first metasomal segment, lateral; 33 — propodeum, dorsal; 34 — metasomal segments 2 and 3, dorsal. Stethantyx orosia, ♀: 35 — head and anterior part of mesosoma, dorsal; 36 — propodeum, dorsal.

FIGURES 56 – 59. Stethantyx spp., ♀, holotypes, habitus: 56 — S. neopropodeator sp. nov.; 57 — S. orellana sp. nov.; 58 — S. sinuata sp. nov.; 59 — S. tiputinia sp. nov. Scales 1.0 mm.