Parancistrocerus extentitergus Qin, Chen, & Li, 2023

Qin, Jiong, Chen, Bin & Li, Ting-Jing, 2023, Additions to the knowledge of the genus Parancistrocerus Bequaert, 1925 from China (Hymenoptera: Vespidae: Eumeninae), Zootaxa 5256 (4), pp. 345-357 : 349-352

Parancistrocerus extentitergus Qin, Chen, & Li , sp. n.

Figs 15–24

Material examined. Holotype, ♀, China, Guizhou Province, Tongren City, Songtao County, Mengxi Town , Jinxing Village , Bajiao Hole , 28°072′N, 108°953′E, 3.VIII.2018, Xue Zhang ( CNU) . Paratype, 1♁, China, Chongqing City, Youyang County, Banqiao Shuangqiao Village , 28°668′N, 108°707′E, 13.VII.2012, Cheng Yang ( CNU) .

Diagnosis. This species is similar to P. elatitergus sp. n. in sharing the character of T2 with a row of dense, large and regular punctures close to margin, with strong preapical bulge. It is easily distinguished from the related species and other members of the genus by the following combination of characters: median sloping area of anterior face of pronotum punctate ( Fig. 19 ), and both T3 and S3 prolonged medially ( Figs 23–24 ), prolongation arch-shaped and narrow.

Description. Female ( Fig. 15 ): body length 7.10 mm. Body black ( Fig. 15 ), with sparse and short setae, with following parts yellow: basal half of clypeus, mandible excluding base, ventral side of scape, apex of ocular sinus, interantennal spot on lower frons ( Fig. 17 ), one small spot on upper gena ( Fig. 19 ), two large anterior separated spots on pronotum, metanotum, tegula mostly, parategula entirely, fore tibia largely, ( Fig. 15 ), apical bands of T1–T2 and S2, and apexes partly of both T3 and S3 ( Figs 23–24 ); fore wing obviously fuscous, hind that pale brown.

Head ( Fig. 17 ). Slightly wider than long in frontal view, maximum width of head 1.25× its length; clypeus densely punctate, clypeal maximum width 1.01× its length, slightly convex, apex emarginate forming two lateral teeth, apical width 0.5× distance between antennal sockets; interantennal area with longitudinal carina; frons coarsely punctate and distinctly reticulate, punctures on vertex and gena similar to those of frons; POL 1.02× OOL; distance between anterior and posterior ocelli 0.5× diameter of anterior ocellus; occipital carina complete ( Fig. 19 ).

Mesosoma. Median sloping area of anterior face of pronotum obviously punctate ( Fig. 19 ), with two small separated foveae medially; pronotal carina tapered dorsally; pronotum, mesoscutum and scutellum coarsely punctate, these punctures similar to those on vertex; median length of mesoscutum 1.02× its maximum width; metanotum with coarse punctures, interspaces carinate and sharp, minutely dentiform ( Fig. 20 ); mesopleuron coarsely punctate and reticulated; epicnemial carina present and strong; metapleuron with few transverse striae; propodeum sloping downward just behind metanotum ( Fig. 20 ), coarsely punctate, punctures large, shallow, flat bottomed and interspaces present as reticulate carinae, dorsal carina weak; posterior face of propodeum slightly concave, with median longitudinal carina, and a few thin and transverse striae; lateral face of propodeum densely with minute transverse striae.

Metasoma ( Figs 22–24 ). Transverse carina of T1 strong and distinct ( Fig. 20 ); vertical anterior face shorter than dorsal horizontal one, dorsal face much wider than long, 1.55× its median length, coarsely punctate, punctures larger than those on mesoscutum, and without regular rows of punctures on yellow band; median length of T2 0.96× its maximum width ( Fig. 15 ), moderately punctate, punctures obviously sparser than those of T1, with a row of dense large and regular punctures close to margin, with strong preapical bulge, margin narrow and smooth, not prolonged medially ( Fig. 23 ); S2 strongly convex basally, medially depressed and with a deep median longitudinal furrow ( Figs 22, 24 ); both T3 and S3 slightly prolonged medially ( Figs 23–24 ), prolongation arch-shaped and narrow; other metasomal segments normal.

Male. Body length 5.9 mm ( Fig. 16 ). Sculpture, setae, and coloration similar to female except as follows: clypeus yellow except apically, clypeal apical width 0.83× distance between antennal sockets; apex of A13 reaching basal fourth of A11 ( Fig. 21 ); T1 much wider than long, 1.75× its median length; T2 short and wide, 0.71× as wide as its median length, punctures on T1 denser than those in female; legs mostly yellow ( Fig. 16 ).

Distribution. China (Chongqing, Guizhou).

Etymology. The specific name extentitergus is derived from two Latin words: extentus (= prolonged) and tergum, referring to both T3 and S3 each with an arch-shaped and narrow prolongation medially.

Figures

FIGURES 15–24. Parancistrocerus extentitergus sp. n., 15, 17, 19, 20, 22–24, holotype, ♀; 16, 18, 21, paratype, ♁. 15– 16. Habitus (dorsal view); 17–18. Clypeus; 19. Head and pronotum (dorsal view); 20. Propodeum and T1 (dorsal view); 21. Antenna; 22. T2 and S2 (lateral view); 23. T2–T6 (dorsal view); 24. S2–S6 (ventral view).