Trieces orientalis, Ranjith & Priyadarsanan, 2022

Ranjith, A. P. & Priyadarsanan, Dharma Rajan, 2022, First description of the metopiine genus Trieces Townes, 1946 (Hymenoptera: Ichneumonidae) from the Indomalayan region with three new species from India, European Journal of Taxonomy 794 (1), pp. 1-17 : 11-15

Trieces orientalis sp. nov.

urn:lsid:zoobank.org:act:0F5BBA69-7733-48FC-970B-FDF2A727CB9A

Figs 5–6

Differential diagnosis

The new species comes closer to T. koreanus but differs based on the characters listed in the taxonomic key. Additionally, T. orientalis sp. nov. differs from the latter in having the following characters: temple distinctly and closely punctate (vs sparse and indistinctly punctate in T. koreanus ), first flagellomeres 1.6× as long as maximum width (vs first flagellomeres 1.9× as long as maximum width in T. koreanus ), first metasomal tergite 0.8× as long as apical width (vs first metasomal tergite 1.7 × as long as apical width in T. koreanus ).

Etymology

The species is named after the distribution extension of the genus to the Indomalayan (= Oriental) region.

Material examined

Holotype INDIA • ♀; Nagaland, Zapami Village ; 25°53.4′ N, 94°24.502′ E; 18–21 Mar. 2021; Malaise trap; A.P. Ranjith leg.; AIMB.

Description

Female

MEASUREMENTS. Body length 4.3 mm, length of fore wing 2.6 mm.

HEAD. Head transverse in dorsal view, not narrowed posteriorly behind eyes, 1.7 × as wide as long medially; frons smooth, setose; occiput smooth, glabrous medially rest setose; temples smooth dorsally, not convex, their length 0.5 × as long as transverse eye diameter in lateral view. Occipital carina present. Eyes sparsely setose. Distance from lateral ocellus to eye equal to diameter of ocellus. Distance between lateral ocellus 1.8× distance from lateral ocellus to eye. Face not convex in lateral view, 0.8 × as wide as long in anterior view, slightly narrowed posteriorly, punctate, setose. Clypeus separated from face by shallow depression, sculptured similarly to face, with lower margin weakly convex in middle. Length of malar space equal to basal width of mandible. Mandible with upper and lower teeth. Antennae with 23 flagellomeres; all flagellomeres longer than wide; first flagellomere 1.6 × as long as maximum width, as long as second flagellomere.

MESOSOMA. Mesosoma 1.6× as long as high; mesonotum densely, closely punctate, interspace smooth, without notauli. Scutellum smooth, closely punctate with distinct lateral carina. Mesopleuron punctate with longitudinal wrinkles posteriorly, setose. Epicnemial carina distinct, reaching anterior margin of mesopleuron. Propodeum punctate with parallel longitudinal dorsal carinae; spiracles small, elliptical, separated from pleural carinae. Metapleuron smooth, setose anteriorly and posteriorly rest glabrous, with distinct longitudinal slit and several short longitudinal rugae ventrally. Fore wing 3.2× as long as wide. Vein 1cu-a distinctly postfurcal. Hind femur 3.0× as long as its maximum width in lateral view. Hind tibia 3.9 × as long as its maximum width. Ratio of length of hind tarsomeres 1–5, 3.8: 1.8: 1.5: 1: 1.7.

METASOMA. Metasoma coarsely and densely punctate. First metasomal tergite 0.8 × as long as apical width, with distinct dorso-lateral and pair of mid longitudinal carinae, ventro-lateral carina absent. Second metasomal tergite 0.8 × as long as its apical width, with distinct dorso-lateral carina and midlongitudinal

carinae. Third metasomal tergite 0.7 × as long as its apical width, with dorso-lateral and midlongitudinal carinae distinct in basal half.

COLOR. Body black except antennae, face, maxillary and labial palps, fore and mid legs, hind coxae apically, hind tibiae, tarsi, metasomal sternites, ovipositor sheath yellow to yellowish brown.

Male

Unknown

Distribution

India (Nagaland).

Biology

Unknown.

Figures

Fig. 5. Trieces orientalis sp. nov., holotype, ♀ (AIMB). A. Habitus, lateral view. B. Head, anterior view. C. Head, dorsal view. D. Mesosoma, dorsal view. E. Head and mesosoma, lateral view. F. Propodeum, dorsal view.

Fig. 6. Trieces orientalis sp. nov., holotype, ♀ (AIMB). A. Metasoma, lateral view. B. Metasoma, dorsal view. C. Fore wing.