Leptochilus (Lionotulus) angulus Bai, Chen & Li sp. nov.

Figs 1-9

Material examined.

Holotype, ♀, China, Inner Mongolia, Urad Front Banner, Xin an Town, Shulin Village, 40.945°N, 108.633°E, 989 m, 3.VIII.2016, Zhenxia Ma (CNU); paratypes, 3♀♀, same data as holotype.

Diagnosis.

This species resembles L. (L.) callidus (Kostylev, 1940) with similar clypeus punctures (Figs 2, 3, 19) and occipital carina (Figs 4, 24). It can be distinguished from the related species and other members of the genus by the following character combination: pronotal carina transparent and obvious (Fig. 5), propodeum with long and undeveloped carina between dorsal and posterior surfaces, posterior surface with oblique and long striae, propodeal carina as long as propodeal concavity (Fig. 7).

Description.

Female. Body length 5.5-6.3 mm (Fig. 1), forewing length 5.4-6.2 mm; black, with the following parts light yellow: basal spot of clypeus (or not), an anterior interrupted band of pronotum dorsally, most of tegula except the median transparent part, apical margin of scutellum, small dorsal spots of mesopleuron (or not), apical margin of femora, tibiae (slightly dark at apical margin) and tarsi, apical bands of T1-T2 (T1 subterminal part ferruginous or not), apical small spots on both sides of S2, and apical sports of T3-T5 in the middle (or not).

Head. In front view, clypeus wider than long (1.4 ×), and apically with emargination wider than depth (2.2 ×-2.5×) (Figs 2, 3), clypeus laterally with dense short white setae; clypeus with small and dense punctures basally, and with bigger and coarser punctures on apical half; frons, vertex and gena with coarse and dense punctures; occipital carina forming obvious angle latero-ventrally (Fig. 4).

Mesosoma. Mesosoma with irregular coarse punctures, interspaces between punctures with minute punctures; mesoscutum on anterior half and mesopleuron ventrally with sparse punctures (Figs 1, 6); pronotal carina transparent and obvious (Fig. 5); metapleuron and lateral surfaces of propodeum with unbroken finely horizontal striae, and lateral surface of propodeum densely striate mixed with irregular punctures (Fig. 6); propodeum with long and undeveloped carina between dorsal and posterior surfaces (Fig. 7); posterior surface with oblique and long striae, propodeal carina present in lower part and half as long as propodeal concavity (Fig. 7).

Metasoma. Metasoma leathery, with smaller and sparser punctures than those on head and mesosoma (Figs 8, 9); punctures of T1 larger than the second metasomal segment, punctures of metasomal segments 2-3 lager than those on metasomal segments 4-6; in dorsal view, the first metasomal segment semi-circular (Fig. 1); the second one with wide apical lamellae and with a row of great punctures at base of lamellae, interspaces between punctures short carina-formed; S2 weak convex in lateral view (Fig. 8), with shallow and long longitudinal medial furrows at base (Fig. 9).

Male. Unknown.

Distribution.

China (Inner Mongolia).

Etymology.

The specific name angulus is derived from Latin word: angulus, referring to occipital carina forming obvious angle latero-ventrally.