Serangium digitiforme Wang & Ren

Wang, Xing-Min, Ren, Shun-Xiang & Chen, Xiao-Sheng, 2011, A review of the genus Serangium Blackburn (Coleoptera, Coccinellidae) from China, ZooKeys 134, pp. 33-63 : 46-51

Serangium digitiforme Wang & Ren sp. n. Figs 2062-6794

Diagnosis.

This species is very similar to Serangium latilobum in general appearance and male genitalia, but it is distinguished from the latter by penis distinctly broadening at apical 1/5-2/5, penis guide widest at base, gradually narrowing to middle (Fig. 65). In Serangium latilobum , penis only has a small pominence at 1/5 (Fig. 57), penis guide wide at basal half, sharply narrowed in middle (Fig. 59).

Description.

TL: 2.14-2.21mm, TW: 1.80-1.85mm, TH: 1.01-1.05mm, TL/TW: 1.19-1.20; PL/PW: 0.46-0.48; EL/EW: 0.95-1.00.

Body minute, hemispherical, dorsum strongly convex, shiny and glabrous (Fig. 20). Dorsum uniformly black. Head dark brown. Underside dark brown. Legs dark red, except tarsi yellow.

Head transverse and ventrally flattened, 0.39 × elytral width (HW/EW=1: 2.60); punctures on frons fine, separated by 1.0-3.0 times their diameter, with sparse setae; eyes moderately large and coarsely faceted, widest interocular distance 0.52 × head width. Antenna 9-segmented, terminal segment large, elongate oval and flat, apex angular.

Pronotum short and strongly transverse, 0.70 × elytral width (PW/EW=1: 1.43), covered in fine and dense punctures associated with moderately dense setae, similar to those on head, separated by 0.5-1.5 times their diameter. Punctures on elytra fine and sparse, slightly smaller than those on pronotum, separated by 2.0-3.0 times their diameter, with a few long setae at humeral angles and a row of evenly spaced setae along margin. Prosternum mat and shagreened, with sparse setae. Mesoventrite glabrous and impunctate, with sparse setae. Metaventrite shiny and glabrous, basal half with distinctly median discrimen; punctures around median discrimen very large and dense, with short thick setae, punctures on the rest parts moderated and sparse, separated by 2.0-4.0 times their diameter, with sparse setae.

Male genitalia. Penis strongly curved in whole length, distinct distinctly broadening at 1/5-2/5, apex narrowing and slightly curved, penis capsule broadening basally and with indistinct inner and outer processes (Fig. 63). Tegmen rather slender and strongly asymmetrical (Figs 64-65). Penis guide in ventral view widest at base, strongly narrowing to middle, then contorted, apical half finger-shape. Left and right paramere in ventral view short, bearing a few long setae (Fig. 65). Penis guide in lateral view widest at base, gradually tapering to apex (Fig. 64).

Female genitalia. Genital plate triangular with a rounded apex, slightly concaved in middle, sparsely hairy on the apical portion, stylus rather long, bearing few setae (Fig. 66). Spermatheca divided into two parts, one of which is somewhat globular with a constriction and two small pinch-like projections, the other is short tubular, becoming slightly more slender distally (Fig. 65).

Type materials.

Holotype: 1♂, China, Hubei: Hongping, Shennongjia National Natural Reserve, 31°40.07'N, 110°25.73'E, ca 1830m, 19.vii.1997, Peng ZQ leg. (SCAU). Paratypes (6): Hubei: 1♂, Liujiawu, Shennongjia National Natural Reserve, 31°33.14'N, 110°21.56'E, ca 1790m, 10.vii.1989, Ren SX leg. (SCAU); Sichuan: 1♂, Liziping, Shimian, 28° 59.75N, 102°18.04'E, ca 2000m, 26.ix.2007, Wang XM leg. (SCAU); Guizhou: 1♂, Lianhuaping, Leigongshan Mountain, Leishan, 26°21.89'N, 108°9.17'E, ca 1240m, 8.x.2008, Liang JB leg. (SCAU); 1♂, Maoping, Leigongshan Mountain, Leishan, 26°22.48'N, 108°9.85'E, ca 1410m, 8.x.2008, Liang JB leg. (SCAU); Gansu: 1♂1♀, Maijishan, Tianshui, 34°20.79'N, 106°0.68'E, ca 1500m, 10.viii.2008, Wang XM leg. (SCAU).

Distribution.

China (Gansu, Guizhou, Hubei, Sichuan).

Etymology.

The specific epithet formed from the Latin noun digitus and forma, referring to digitiform penis guide.