Longitarsus xinjiangensis Liang, Konstantinov & Ge, 2023

Liang, Zulong, Konstantinov, Alexander S., Ruan, Yongying, Li, Zhiqiang, Huang, Zhengzhong & Ge, Siqin, 2023, Two new species of the Longitarsus violentus group from China (Coleoptera, Chrysomelidae, Galerucinae, Alticini), ZooKeys 1181, pp. 111-123 : 111

Longitarsus xinjiangensis Liang, Konstantinov & Ge sp. nov.

Figs 2a-j , 3b

Type materials.

Holotype: ♂ (IZCAS) Xinjiang, Tianshan, Wukuerqi, 1120 m, 7 August 1957, Weiyi Yang leg.; Paratypes: 4♀ (IZCAS) Tianshan, Wukuerqi, 1620 m, 7 August 1957; 2♂ (IZCAS) Xinjiang, Zhaosu, Wukuerqi, 1120-1620 m, 7 August 1957, Chunpei Hong leg.; 1♂ (IZCAS) Xinjiang, Zhaosu, Wukuerqi, 1120-1620 m, 7 August 1957, Guang Wang leg.; 1♂ (IZCAS) Xinjiang, Zhaosu, 1630 m, 11 August 1957, Chunpei Hong leg.; 1♂ 2♀ (IZCAS) Xinjiang, Burqin, 27 July 1955, Shijun Ma, Kailin Xia and Yonglin Chen leg.; 1♀ (IZCAS) Xinjiang, Burqin, 27 July 1955, Yonglin Chen et al. leg.; 1♂ (IZCAS) Xinjiang, Tacheng, 24 July 1955, Shijun Ma, Kailin Xia and Yonglin Chen leg.; 2♀ (IZCAS) Xinjiang, Urumqi, 14 July, 1956 Weiyi Yang leg.; 1♀ (IZCAS) Xinjiang, Urumqi, 20-890 m, 14 July 1959, Weiyi Yang leg.; 1♀ (IZCAS) Xinjiang, Xinyuan, 820-1200 m, 23 August 1957, Chunpei Hong leg.; 1♀ (IZCAS) Xinjiang, Xinyuan, 870-1220 m, 23 August 1957, Guang Wang leg.; 1♀ (IZCAS) Xinjiang, Tianshan, 2040 m, 13 August 1957, Guang Wang leg.; 1♂ (IZCAS) Xinjiang, Xiaotalate, 9 August 1956, Weiyi Yang leg.; 1♀ (IZCAS) Xinjiang, Jimsar, 14 May 1955, Shijun Ma and Yonglin Chen leg.; 1♀ (IZCAS) Xinjiang, Chaiwobao, 20 July 1956, Weiyi Yang leg.

Description.

Male body length 1.65-1.72 mm, width 0.78-0.90 mm; female body length 1.87-2.08 mm, width 0.89-1.18 mm. Body integument dark brown to black with bronze reflection. Apical part of antennomeres I-III yellowish to ferruginous, the rest part of antennae piceous. Legs ferruginous to piceous, metafemur black; dorsum with bronze reflection (Fig. 2a, b ).

Head. Vertex strongly shagreened, with well-developed supraorbital punctures near orbital sulcus. Antennal calli poorly developed, subtriangular, barely delimited from vertex, surface smooth (Fig. 2c ). Orbital sulcus well developed, extending from top of eye to antennal socket. Midfrontal and suprafrontal sulci absent. Frontal ridge wide and convex. Distance between antennal sockets 2.28 times as great as diameter of antennal socket. Anterofrontal ridge in middle as high as frontal ridge, slightly narrower than frontal ridge. Antennae short, length of antenna ca 0.61 times as long as body length, ratio of length of each antennomere 20: 13: 11: 15: 16: 13: 16: 15: 16: 14: 20. Antennomere II longer than III, but shorter than IV.

Thorax. Pronotum transverse, 1.44 times as wide as long. Lateral sides slightly convex, with maximum width at middle. Lateral margin of pronotum slightly angulate in front of middle (Fig. 2d ). Anterolateral callosity well developed, slightly lower anteriorly, forming acute angle. Lateral margin narrowly explanate. Posterolateral callosity low, slightly prominent. Punctures large and dense, well defined, distance of interspace 0.9-1.7 times as diameter of punctures. Interspaces strongly shagreened, weaker in lateral area (Fig. 2d ). Scutellum triangular, narrowly rounded apically, surface strongly shagreened. Elytra 3.86 times as long as pronotum, with well-developed humeral callus; maximum width behind middle. Apex broadly rounded. Punctures slightly larger and denser than those on pronotum, larger near suture, width of interspaces 0.9-1.1 times as diameter of punctures. Interspaces weakly shagreened basally. Hind wings well developed.

Leg. Metatarsomere I of male 0.51 times as long as metatibia, 1.07 times as long as metarsomeres II-IV combined (Fig. 2a ). Metatibial spur 0.66 times as long as width of metatibia. Tarsal claw simple, without denticle.

Abdomen. Distal part of preapical abdominal tergite of female with two subquadrate areas on each side near apical part covered by short dense setae. Apical abdominal tergite covered with long setae. A few tiny microtrichia situated at middle (Fig. 3b ).

Male genitalia. Median lobe of aedeagus in ventral view with sides nearly parallel to each other, apex with poorly developed denticle. Ventral groove wide (Fig. 2e ). Apical part dorsally with rectangular membranous window (Fig. 2f ). Median lobe narrow in lateral view (Fig. 2g ), curved above the basal opening, dorsal side and ventral side both convex apically.

Female genitalia. Receptacle of spermatheca oval, 1.58 times as long as wide. Inner side of receptacle more convex than outer side. Basal part of pump rather long, about half as long as apical part, well delineated from receptacle and from apical part of pump; apical part longer than width of receptacle, widely rounded apically. Spermathecal duct forms two U-shaped turns (Fig. 2h ). Tignum slender, slightly curved, dilated apically (Fig. 2i ). Vaginal palpus slender, posteriorly straight, rounded at apex (Fig. 2j ).

Differential diagnosis.

The key below allows for distinguishing L. xinjiangensis from all other species in the group. In addition, L. xinjiangensis is similar to L. violentus and L. violentoides . However, the elytra of L. xinjiangensis are slender, and the punctures on pronotum are larger. Compared to L. violentus , the antennomeres IV-VI of L. xinjiangensis are much darker, the median lobe of the aedeagus is broader, and the apex lacks an obvious denticle. Besides, the apex of the spermathecal pump of L. xinjiangensis is broader than that of L. violentus , and the spermathecal duct forms two U-shaped turns instead of loops. Longitarsus xinjiangensis can be distinguished from L. violentoides by the following characters: antennomere II shorter than IV; aedeagus narrow in lateral view; and apical part of spermathecal pump longer than width of receptacle.

Etymology.

The species is named after the type locality. The epithet is a noun in apposition.

Distribution.

Known from northern Xinjiang, China.

Host plant.

Unknown.

Figures

Figure 2. Longitarsus xinjiangensis Liang, Konstantinov & Ge, sp. nov. a, b habitus (a dorsal view b lateral view) c head d pronotum e-g median lobe of aedeagus (e ventral view f dorsal view g lateral view) h spermatheca i tignum j vaginal palpi.

Figure 3. Last two tergites of female a Longitarsus pekingensis Liang, Konstantinov & Ge, sp. nov. b Longitarsus xinjiangensis Liang, Konstantinov & Ge, sp. nov.