Unicarinata Sheng, Li & Sun, 2022

Li, Tao, Sun, Shu-Ping & Sheng, Mao-Ling, 2022, A new genus and species of Ctenopelmatinae (Hymenoptera, Ichneumonidae) from China, Journal of Hymenoptera Research 92, pp. 199-210 : 199

Unicarinata Sheng, Li & Sun gen. nov.

Type species.

Unicarinata ventrialis Sheng, Li & Sun, sp. nov. Monotypic.

Diagnosis.

Mandible (Fig. 3 ) large and long, lower tooth distinctly longer than upper tooth. Occipital carina complete, genal carina joining hypostomal carina above base of mandible. Dorsal end of epicnemial carina (Fig. 4 ) almost reaching front edge of mesopleuron. Areolet absent (Fig. 11 ). Vein 2rs-m basal to vein 2m-cu. Hind vein 2-cu absent. Propodeum (Fig. 8 ) with one strong transverse carina level with posterior edge of spiracle. Tergite 1 (Fig. 13 ) very long and slender; latero-median carina absent, dorso-lateral carina present after spiracle; spiracle located slightly anterior to middle; tergite and sternite fused; glymma absent. Ovipositor sheath (Fig. 12 ) almost extending to apex of metasoma. Ovipositor slender and straight.

Etymology.

The name of the new genus is derived from the propodeum having one strong transverse carina. The gender is feminine.

Remarks.

The new genus is similar to Syntactus Förster, 1869 in having the apical margin of the clypeus blunt; base of the mandible without a transverse impression; dorsal end of epicnemial carina almost reaching the front edge of the mesopleuron; glymma absent; areolet absent; however, it can easily be distinguished from Syntactus by the following characters in combination: apical margin of clypeus medially almost truncate (Fig. 3 ); propodeum with only one strong transverse carina (Fig. 8 ); area superomedia entirely absent; hind vein 1-cu opposite cu-a; vein 2-cu absent; tergite 1 (Figs 12-14 ) very slender, straight; tergite 2 (Fig. 15 ) granulate; and ovipositor (Fig. 12 ) straight. In Syntactus the apical margin of the clypeus is almost evenly arcuate; propodeum is completely areolated, area superomedia at least partly present; tergite 1 relatively slender, decurved; tergite 2 smooth; and ovipositor upcurved.

In Townes’ (1970) key to Pionini genera, the new genus can be inserted as follows:

2	Outer face of mandible without a basal transverse impression. Subbasal part of lower edge of mandible sharp. Areolet absent	3
-	Outer face of mandible with a basal transverse impression. Subbasal part of lower edge of mandible rounded. Areolet present or absent	4
3	Propodeum (Fig. 8 ) with only one distinct median transverse carina, lateromedian longitudinal carinae entirely absent. Tergite 1 very slender, straight (Figs 12-14 ). Tergite 2 (Fig. 15 ) shagreened, without punctures. Ovipositor (Fig. 12 ) straight	Unicarinata Sheng, Li & Sun, gen. nov.
-	Propodeum at least with posterior transverse carina, lateromedian longitudinal carinae present. Tergite I decurved. Tergite II smooth, punctate. Ovipositor upcurved	3 '

Figures

Figure 3 - 11. Unicarinata ventrialis Sheng, Li & Sun, sp. nov. Holotype, ♀ (CBDPC) 3 head, anterior view 4 head and mesosoma, lateral view 5 head, dorsal view 6 basal of flagellomeres, ventral view 7 mesoscutum and scutellum, dorsal view 8 propodeum, dorsal view 9 fore tibia, lateral view 10 hind tarsus, lateral view 11 wings. Scale bars: 0.2 mm (3 - 7); 0.1 mm (8, 9); 0.4 mm (10, 11).

Figure 12 - 15. Unicarinata ventrialis Sheng, Li & Sun, sp. nov. Holotype, ♀ (CBDPC) 12 metosoma, lateral view 13 tergite 1, dorsal view 14 tergite 1, lateral view 15 tergites 2, 3 dorsal view. Scale bars: 0.2 mm (12 - 15).