Lesticus violaceous, 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 violaceous sp. n. Figs 10-13

Type locality.

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

Type material.

Holotype: male (IZAS), body length = 25.1 mm, pin mounted, genitalia preserved in 100% ethanol in a microvial pinned under specimen, "China, Yunnan, Yingjiang / Nabang power station, 473m / 2016-V-29, light trap, 16Y / Yang Xiaodong Leg. CCCC"; "HOLOTYPE ♂ / Lesticus violaceous sp. n. / des. ZHU & SHI 2018" [red label].

Diagnosis.

Pronotum metallic bluish violet, elytra completely violet; pronotum lateral margins slightly sinuate before posterior angles; pronotal basal fovea deep and glabrous, with very faint wrinkles; long, narrow metepisternum, length much greater than its basal width (L/W = 1.78), distinctly punctated; median lobe of aedeagus not expanded ventrally, apex markedly deflexed to right, very short apical lamella, apex a little truncated.

Comparisons.

Among all Lesticus species from China, this new species is the only one with similar distinctly metallic color on the pronotum and elytra. From the slightly sinuate pronotal lateral margins and glabrous basal fovea, the new species is somewhat similar to L. tristis and L. chalcothorax . Besides their different color and body size, the two other species also differ from the new species in: median lobe of aedeagus distinctly expanded ventrally, apex of apical lamella more rounded.

The new species is also similar to L. desgodinsi from N. India and L. episcopalis from N. Myanmar in having a violet color on the elytra and pronotum as well as the pronotal lateral margins being somewhat sinuate before the posterior angles. Compared with the latter two species, L. violaceous sp. n. has less sinuate pronotal lateral margins; pronotal basal fovea less punctate; and ventral margin of aedeagus straight, not expanded near middle.

Description.

Body length 25.1 mm, elytra’s greatest width 9.2 mm. Head black, pronotum and elytra violet, with strong metallic lustre, pronotum somewhat blue in basal fovea and lateral channel; appendages black; tarsomeres, apical antennomeres, palpomeres and lateral sides of labrum reddish brown; ventral side black, with slightly metallic violet lustre. Head and pronotum with isodiametric microsculpture and minute punctures; elytra with isodiametric microsculpture.

Head glabrous, without coarse puncture and wrinkle; frontal impressions deep, with a few fine punctures inside; anterior margin of labrum slightly emarginate; temporae not tumid behind eyes; antennal apex reaching elytra basal tenth.

Pronotum much wider than head, PW/HW = 1.54, slightly transverse, PW/PL = 1.31, widest near middle. Lateral margins not crenulate; evenly curved at anterior two-thirds, slightly sinuate before posterior angles; posterior angles obtusely angulate, not pointed outwards; posterior margin a little narrower than anterior margin, extended slightly backward on each side. Median line deep, not reaching posterior margin; disc glabrous, without wrinkles. Basal fovea deep and narrow, inner groove nearly straight, about same length as outer one which is strongly curved, region between them deeply depressed; basal foveal area nearly glabrous, with a few very fine punctures and shallow 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, sparse punctures alongside; scutellar stria long, apex free; parascutellar pore present on base of first stria; third interval with three setigerous pores: first one close to third stria, the 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 with sparse, coarse punctures, a little denser on mesopleuron; long, narrow metepisternum, length much greater than its basal width (L/W = 1.78), with sparse, coarse punctures; abdominal sterna glabrous, almost impunctate, with only very shallow wrinkles on lateral sides.

Legs: basal two meso- and metatarsomeres with distinct 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 straight, not expanded in middle, apical portion slightly turned dorsally before apical lamella, basal portion slightly narrowed; in dorsal view, aedeagus narrow, apical lamella very short, length approximately one-third of basal width, apex a bit truncated, apical fourth distinctly oriented to left side. Endophallus (Fig. 13) extending to dorsal-left, major portion of endophallus on left-dorsal side of aedeagus when everted; gonopore (gp) located at well before apical lamella, oriented to aedeagal base; gonopore lobe (gpl) long, a little spiral. Basal tubercle (bt) and basal band (bb) typical of the genus. Six distinct lobes recognized: dorsal lobe (dl) very large and compressed, on dorsal-right surface, pointing to base of aedeagus; one additional basal lobe (bl) present on basal-ventral side of dl, small and rounded, apex decorated with fine scales; right basal lobe (rb) large and wide, extended to ventral side of endophallus, surface with longitudinal impression; right apical lobe (ra) smaller than rb, rounded, at right-apical side of rb, at right surface of endophallus and close to gp; left basal lobe (lb) a little larger than rb, rounded, at ventral-apical side of rb, at ventral surface of endophallus; left apical lobe (la) small and compressed, close to left side gp, apex a little dilated and bifid.

Distribution.

This species is known only by the holotype which was collected from Yunnan, Yingjiang, Nabang (Map 3).

Etymology.

The scientific name " violaceous " comes from Latin, referring to the violet coloration of this new species.

Affinities.

Among all Chinese Lesticus with the endophallus known, only L. rotundatus has similar male endophallic characters to the new species: endophallus strongly deflexed to left-dorsal side of aedeagus; gonopore pointed to the aedeagal base. Thus, a close relationship of these two species is possible, although they have quite different external and aedeagal characters.