Casinaria exiloides Han, van Achterberg & Chen, 2021

Han, Yuan-Yuan, Achterberg, Kees Van & Chen, Xue-Xin, 2021, The genus Casinaria Holmgren, 1859 (Hymenoptera: Ichneumonidae, Campopleginae) from China, Zootaxa 4974 (3), pp. 504-536 : 515-517

Casinaria exiloides Han, van Achterberg & Chen , sp. nov.

Figs. 7–8

Material examined. Holotype: female, Zhejiang, Tianmushan , 27.VII.2003, Yu Xiaoxia, No20038222 . Paratypes: 2 females, Fujian, Nanjing Letu , 8.VII.1991, Liu Changming, No 20006241, 20006166 ; 1 female, Guangdong, Conghua Liuxihe , 13–14.IV.2002, Xu Zaifu, No 20027042 ; 1 male, Zhejiang, Hangzhou Nangaofeng, Shi Min, No 20056292 ; 1 male, Zhejiang, Hangzhou Yuhuangshan , 20.VII.2003, Shi Min, No 20057084 .

Description. Female holotype. Body length 7.5 mm, fore wing length 4.7 mm.

Head. Antenna with 34 flagellomeres; basal flagellomeres relatively slender, first flagellomere about 3.0× longer than wide apically. Head transverse, width 2.7× its length in dorsal view. Temple narrow behind eye, in dorsal view about 0.6× as long as eye width. Interocellar distance about 1.7× ocello-ocular distance, 1.9× between median and lateral ocelli and 1.3× diameter of ocelli. Inner eye orbits indented and weakly convergent ventrally. Genal carina slightly bent outwards ventrally, reaching hypostomal carina at mandibular base. Malar space 0.6× as long as basal width of mandible. Face rugose, flat in profile, narrowed ventrally, minimal width of face 0.7× as long as eye length and 0.9× as long as width of frons. Clypeus granulate-rugulose, weakly convex in profile, apical margin convex.

Mesosoma. Pronotum rugulose above, trans-striate below. Mesoscutum granulate-punctate, tending to become rugulose in notaulic area. Scutellum and metascutellum rugose-punctate. mesopleuron rugulose-punctate above, rugulose below, trans-striate below subtegular ridge; speculum mat with very fine striate. Metapleuron rugosepunctate, with lower portion rugose, juxtacoxal carina indistinct. Propodeum rugulose on sides, rugose-reticulate dorsally, with median groove relative broad and deep, trans-striate; basal carina close to base; medio-longitudinal carina absent; lateral longitudinal carina indistinct; apical transverse carina distinct on sides and costulae absent; propodeal spiracle oval.

Wing. Fore wing areolet small with a short stalk emitting second recurrent vein from its apical part. Radial cell very short, distal part of surrounding vein about 1.8× longer than the proximal one. Nervulus a little distad of basal vein. External angles of discal cell acute (70°). Hind wing with nervellus a little reclivous, not intercepted.

Legs. Hind femur 4.4× longer than wide. Inner spur of hind tibia about 0.7× as long as first tarsomere of hind tarsus.

Metasoma. Apical tergites from the 3th on compressed. First tergite short, stout, widened apically, 3.4× longer than its apical width, about 1.4× longer than second tergite, as long as hind femur. Second tergite 2.0× longer than its apical width; thyridium drop-shaped, its distance from basal margin of tergite about its 1.3× length. Third tergite 1.1× longer than its apical width. Ovipositor sheath short, not extending behind metasomal apex.

Colour. Black. Mandible except teeth yellowish brown. Scape and pedicel yellowish brown. Tegulae brown. Fore and mid leg yellowish brown with trochanters apically, trochantellus, femur apically and outward of tibia whitish yellow, mid coxa brown; hind coxa blackish brown, trochanters yellowish brown, femur yellowish brown with apically whitish, tibia yellowish brown with basally whitish, tarsus brown. First and second metasomal tergites black with its apical reddish brown, remainder of the metasoma yellowish brown.

Variation. Antenna with 34–36 flagellomeres; first flagellomere 2.7–3.0× longer than wide apically. Face rugose-punctate to rugose; minimal width of face 0.7–0.8× as long as eye length and 0.9–1.0× as long as width of frons. Interocellar distance 1.8–2.0× ocello-ocular distance. Hind femur 4.2–4.4× longer than wide, inner spur of hind tibia 0.7–0.8× as long as first tarsomere of hind tarsus. First tergite 3.4–3.7× longer than its apical width; second tergite 1.8–2.0× longer than its apical width.

Male. Same as the female.

Distribution. China (Fujian, Guangdong, Zhejiang).

Comparison. This new species is similar to C. exilis sp. nov., but differs from the latter by having the malar space 0.6× as long as basal width of mandible, genal carina slightly bent outwards ventrally, reaching hypostomal carina at mandibular base, interocellar distance 1.3× diameter of ocelli, minimal width of face 0.7× as long as eye length, and speculum mat with very fine striate.

Etymology. Name derived from “exilis”, the name of related species, and the suffix “oides”, because it is similar to C. exilis sp. nov.

Figures

FIGURE 7. Casinaria exiloides sp. nov., female, habitus.

FIGURE 8. Casinaria exiloides sp. nov., female. A, fore wing; B, mesopleuron; C, propodeum; D, head, anterior view; E, head, dorsal view; F, mesoscutum.