Lesticus xiaodongi, Zhu, Pingzhou, Shi, Hongliang & Liang, Hongbin, 2018

Zhu, Pingzhou, Shi, Hongliang & Liang, Hongbin, 2018, Four new species of Lesticus (Carabidae, Pterostichinae) from China and supplementary comments on the genus, ZooKeys 782, pp. 129-162 : 129

Lesticus xiaodongi sp. n. Figs 14-17

Type locality.

China, Yunnan: Yingjiang, Nabang (24.71°N, 97.58°E), altitude 473 m.

Type material.

Holotype: male (IZAS), body length = 27.0 mm, pin mounted, genitalia preserved in 100% ethanol in a microvial pinned under specimen, "China, Yunnan, Yingjiang / Nabang power station, 473m / 2016-V-27, light trap, 16Y / Yang Xiaodong Leg. CCCC"; "HOLOTYPE ♂ / Lesticus xiaodongi sp. n. / des. ZHU & SHI 2018" [red label].

Diagnosis.

Dorsal side bicolor : head and pronotum metallic bluish green, elytra dark metallic blue; pronotum lateral margins strongly sinuate before posterior angles; pronotal basal fovea deep, with fine punctures and wrinkles; posterior angles a little pointed; metepisternum long and narrow, length greater than its basal width (L/W = 1.35); median lobe of aedeagus slightly expanded ventrally, apical lamella very short, slightly thickened.

Comparisons.

The new species can be readily distinguished from all the other known species from China by pronotal lateral margins strongly sinuate near base. From the coloration, shape of pronotum and median lobe of aedeagus slightly expanded ventrally, this new species is most similar to L. waterhousei Chaudoir from N.E. India and L. peguensis Bates from S. Myanmar. L. waterhousei differs in: much larger size (33-36 mm), pronotal basal fovea coarsely rugose, and apical lamella of aedeagus much longer. Lesticus peguensis differs in: pronotal posterior angles not pointed at all; apical lamella a little longer and not thickened.

Description.

Body length 27.0mm, elytra’s greatest width 9.7 mm. Dorsal side bicolor , head and pronotum metallic bluish green, elytra dark metallic blue; mouth part, clypeus, and appendages black; tarsomeres, apical antennomeres, terminal palpomeres reddish brown; ventral side black, without metallic lustre. Head, pronotum and elytra with isodiametric microsculpture and minute punctures.

Head: vertex nearly glabrous, with very fine shallow wrinkles; frontal impressions deep; coarse longitudinal wrinkles along inner margins of eyes; anterior margin of labrum distinctly emarginate; temporae not tumid behind eyes; antennal apex reaching elytra basal sixth.

Pronotum much wider than head, PW/HW = 1.52, slightly transverse, PW/PL = 1.32; widest near middle. Lateral margins not crenulate, evenly curved in middle, strongly sinuate before posterior angles; posterior angles nearly rectangular, pointed a little outward; posterior margin a little narrower than anterior, extended backward on each side. median line is deep, not reaching posterior margin; disc with very shallow transverse wrinkles alongside median line. Basal fovea deep, inner groove straight, a little longer than curved outer groove, region between them deeply depressed; basal foveal area with some fine but distinct punctures and wrinkles.

Elytra oviform, EL/EW = 1.65, gradually widened to apex, widest near posterior third; basal ridge complete, forming an indistinct obtuse angle with elytral lateral margin, humeral teeth not pointed. Intervals barely convex, striae deeply incised, with fine and dense punctures alongside; scutellar stria moderately long, apex conjoined to first stria; parascutellar pore located at base of first stria; third interval with three setigerous pores: first one close to third stria, other two close to second; umbilicular series on ninth interval composed of approximately 25 pores, sparse in middle and dense in anterior and posterior areas. Hind wings well developed.

Ventral side: propleuron and mesopleuron with dense, coarse punctures; metepisternum long and narrow, length greater than its basal width (L/W = 1.35), with sparse, coarse punctures; abdominal sterna glabrous in middle, with dense, coarse punctures on lateral sides of sternum II and sternum III, and shallow wrinkles on lateral sides of all sterna.

Legs: three basal metatarsomeres with distinct carina along almost the full length of outer surface, three basal mesotarsomeres, and fourth with weaker carina only near base; fifth tarsomeres with 3-4 pairs of spines ventrally.

Male genitalia: median lobe of aedeagus with apical orifice opened dorsally; in lateral view, ventral margin slightly expanded in middle, basal portion not narrowed, apical lamella slightly thickened and turned ventrally; in dorsal view, aedeagus gradually narrows from middle to apex, apical lamella very short, length approximately one-third of basal width, apex a little truncated; apical portion a little inclined to right side. Endophallus (Fig. 17) straight, extending to apex, the included angle between axes of aedeagus and endophallus about 20°; major portion of endophallus located beyond apical lamella, inclined a little to left; gonopore (gp) located at well beyond apical lamella, oriented to aedeagal apex; gonopore lobe (gpl) long, a little spiral. Basal tubercle (bt) typical of the genus; basal band (bb) short, obsolete at apex, not reaching left surface of dl. Five distinct lobes recognized: large dorsal lobe (dl), divided into three sub-lobes by longish grooves: basal one longitudinal; middle one on right side of basal one, very narrow and transverse; apical one transverse, larger than the other two, without scales; single right basal lobe (rb), large and rounded, on right-apical side of dl, decorated with dense scales; right apical lobe (ra) smaller than rb, rounded, close to gp; left basal lobe (lb) very large and flat, near apex of bb; left apical lobe (la) very small, nearly imperceptible.

Distribution.

This species is known only by the holotype, which was collected from Yunnan, Yingjiang, Nabang, the same locality as the previous new species (Map 4).

Etymology.

The new species is named for our friend Mr. Yang Xiaodong, who collected the holotype of this beautiful and rare new species.

Affinities.

Among all Chinese Lesticus we studied, L. tristis and L. solidus have the most similar male endophallic characters to the new species: endophallus straight, major portion extending to apical direction of aedeagus; in lateral view, the angle between axes of endophallus and aedeagus less than 30°. Moreover, these three species all have pronotal basal fovea not well punctated, and metepisterna much longer than its basal width. This suggests a close relationship among the three species.