Dascillus levigatus, Li & Ślipiński & Jin, 2017

Li, Fengming, Ślipiński, Adam & Jin, Zhenyu, 2017, Description of a new species of Dascillus Latreille from Yunnan, China (Coleoptera: Dascillidae), Zootaxa 4341 (3), pp. 433-436 : 433-435

Dascillus levigatus sp. n. ( Figs 1–11 , 13, 15, 17–19)

Etymology. The species name refers to the body upper surface glabrous; adjective.

Diagnosis. This species closely resembles D. pallidofemoratus Pic, 1911 but can be distinguished by the head not obviously depressed at apex in dorsal and lateral view (Figs 13, 15) and elytra indistinctly pubescent in both genders, phallobase emarginate at base in males while females with spiculum ventrale also emarginate apically ( Fig. 11 ).

Description. Male ( Fig. 2 ). Length 14.3–14.5 mm, width 5.4–5.5 mm. Body 2.5–2.6× longer than broad. Head, antennae, pronotum, scutellar shield, elytra and venter black, legs brown. Elytral feebly shiny, glabrous. Head, scutellar shield and pronotal margin setae brown, not forming colour pattern, venter covered by brown dense pubescence.

Head. Antennae reaching middle of elytra. Antennomere 3 about 3.2–3.3× as long as broad, 1.0–1.1× as long as antennomere 4; terminal antennomere slightly longer than penultimate. Mandible strongly curved apically; incisor edge with two teeth. Apical palpomere of both maxilla and labium cylindrical to fusiform.

Pronotum trapezoidal, 0.5–0.6× as long as wide, widest just before base; sides sinuate. Lateral carina narrowly explanate with marginal bead, edge smooth with distinct fringe of setae; anterior angles broadly rounded. Disc strongly convex, punctation coarse and dense.

Pterothorax. Scutellar shield 0.8–0.9× as long as wide, obtuse anteriorly, acute posteriorly. Elytra moderately convex, together 1.9–2.0× as long as wide, 4.3–4.4× as long as pronotum.

Abdominal ventrites ( Fig. 9 ) with glabrous spots on each side; ventrite 5 with apex distinctly projected medially, 0.5–0.6× as long as wide, 1.2–1.3× as long as ventrite 4. Sternite IX ( Fig. 6 ) apically emarginate, at base obtuse, bearing uniformly short setae in middle and apical part. Posterior edge of tergite IX ( Fig. 7 ) also emarginate. Tergite X as long as tergite IX, apically rounded.

Aedeagus ( Figs 3–5 ). Phallobase emarginate at base. Parameres slightly shorter than phallobase, inner margin upturned apically, slender and narrowly rounded at apex. Ventral lobe obtuse at apex; dorsal lobe broadly rounded at apex.

Female ( Fig. 1 ). Externally identical to male except for abdominal ventrite 5 ( Fig. 8 ) rounded. Female genitalia weakly sclerotised with vagina and bursa copulatrix not clearly separated; bursa copulatrix without sclerites; spermatheca small and not sclerotised. Ovipositor ( Fig. 10 ) short; paraprocts entirely sclerotised, without baculi, about as long as gonocoxites; proctiger absent; gonocoxites entirely sclerotised ventral of paraprocts, triangular and strongly bent, apices prominent, densely setose dorsally, without baculi; gonostyli absent.

Type material. Holotype (1 ♂): Yunnan, Gongshan County, Dulongjiang township, 23-v-2013, Hao Xu , Jianyue Qiu ( YZU).

Paratypes (2 ♂, 6 ♀♀): Yunnan, Gongshan County, Dulongjiang township, 23-v-2013, Hao Xu, Jianyue Qiu (1 ♂, 4 ♀♀, YZU); Tibet, Bomi Country, Zhamu Town, 12-vii-2016, Hao Xu, Jianyue Qiu (1 ♂, 2 ♀♀, YZU).

FIGURES 13–16. (13, 15) Dascillus levigatus sp. n.; (14, 16) D. pallidofemoratus ; (13–16) head: (13–14) dorsal view; (15–16) lateral view.

Distribution. China: Yunnan, Tibet ( Fig. 19 ).

Natural history. The natural history of Dascillinae is poorly known, but adults of Dascillus Latreille are often collected on foliage or flowers (Lawrence 2016). Some females of D. levigatus sp. n. were observed feeding on pollen of Castanea sp. ( Fagales : Fagaceae ) in Dulongjiang township ( Fig. 17 ) and Hydrangea sp. ( Rosales : Saxifragaceae ) in Zhamu Town ( Fig. 18 ).

Figures

FIGURE 19. Distribution of Dascillus levigatus sp. n. (red circles).

FIGURES 1 – 12. (1 – 11) Dascillus levigatus sp. n.; (12) D. pallidofemoratus; (1 – 2) habitus: (1) female, (2) male, (3 – 5) aedeagus: (3) ventral; (4) dorsal; (5) lateral; (6) male abdominal sternite IX; (7) male abdominal tergites IX – X; (8 – 9) abdomen: (8) female; (9) male; (10) ovipositor; (11 – 12) spiculum ventrale.

FIGURES 17 – 18. Habitats of Dascillus levigatus sp. n. Adult: (17) Dulongjiang township, Gongshan County, Yunnan, China, by Hao Xu; (18) Zhamu Town, Bomi County, Tibet, China, by Hao Xu.