Chaetocnema (Chaetocnema) yulongensis Ruan, Konstantinov & Yang, 2014

Ruan, Yongying, Yang, Xingke, Konstantinov, Alexander S., Prathapan, Kaniyarikkal D. & Zhang, Mengna, 2019, Revision of the Oriental Chaetocnema species (Coleoptera, Chrysomelidae, Galerucinae, Alticini), Zootaxa 4699 (1), pp. 1-206 : 123-125

50. Chaetocnema (Chaetocnema) yulongensis Ruan, Konstantinov & Yang, 2014

( Fig. 71 )

Chaetocnema (Chaetocnema) yulongensis Ruan, Konstantinov & Yang, 2014: 67 . TL: China (Yunnan); TD: IZCAS.

Distribution: China (Yunnan).

Host plants: Unknown.

Description: Body length: 1.66–2.15 mm. Body width: 0.92–1.17 mm. Ratio of length of antenna to length of body: 0.60–0.61. Ratio of elytron length (along suture) to width (maximum): 2.54–2.65. Ratio of pronotum width (at base) to length: 1.72–1.73. Length of elytron to length of pronotum (along middle): 3.25–3.30. Ratio of width of elytra at base (in middle of humeral calli) to width of pronotum at base: 1.10–1.15. Ratio of maximum width of elytra to maximum width of pronotum: 1.41–1.43.

Dorsum coppery. Antennomere 1 partially dark brown, 2–4 completely yellow, 5 partially brown, 6–11 brown. Protibia partially brown. Meso- and metatibia partially brown. All femora brown.

Head hypognathous. Frontal ridge narrow and convex. Frontolateral sulcus present. Orbital sulcus deep. Suprafrontal sulcus deep laterally, shallow in middle. Suprafrontal sulcus obcordate. Ratio of width of frontal ridge (excluding margin) to width of antennal socket (excluding margin): 0.86–0.90. Ratio of width of orbital sulcus to width of frontolateral sulcus: 0.54–0.61. Number of punctures on vertex: 8–12. Number of punctures on orbit: 2. Number of setae along frontolateral sulcus: 8–9. Number of punctures on frons (triangular area surrounded by frontolateral sulcus and clypeus): 0. Number of setae on clypeus: 7. Number of setae on labrum: 6. Anterior margin of labrum slightly concave in middle.

Pronotum with two obscure longitudinal impressions visible only near basal margin. Deep row of large punctures near basal margin of pronotum distinct laterally, absent in middle. Pronotal base evenly convex. Lateral margins of pronotum slightly convex, converging forward. Anterolateral prothoracic callosity protruding laterally, forming rounded anterolateral corners. Posterolateral prothoracic callosity poorly developed. Diameter of pronotal punctures 2 to 4 times smaller than distance between them.

Elytra with convex sides. All elytral rows of punctures, including peri-scutellar, regular and single. Humeral callus well developed. Interspaces between striae of punctures smooth and glabrous. Number of rows of minute punctures on each interspace: 2.

First male protarsomere slightly larger than second. First male protarsomere, length to width ratio: 1.64–1.70. Ratio of lenth of first and second male protarsomeres: 1.57–1.62. Ratio of width of first and second male protarsomeres: 1.03–1.04. First male protarsomere, width at apex to width at base ratio: 1.53–1.58. Ratio of length of metatibia to distance between denticle and metatibial apex: 2.38–2.41. Large lateral denticle on metatibia sharp. Metatibial serration proximal to large lateral denticle present, obtuse. First male metatarsomere, length to width ratio: 2.63–2.73. First and second male metatarsomeres, length to length ratio: 1.91–2.04. First and second male metatarsomeres, width to width ratio: 0.93–0.96. Third and fourth male metatarsomeres, length to length ratio: 0.60–0.61.

Apical third of aedeagus narrowing with polygonal marks on sides. Apex in ventral view narrowing abruptly. Ventral longitudinal groove absent. Apical denticle in ventral view absent. Minute transverse wrinkles on ventral side absent. Aedeagus in lateral view evenly and slightly curved with apex sinuated. Maximum curvature in lateral view situated medially.

Spermathecal receptacle oblong. Basal part of spermathecal duct straight. Spermathecal pump much shorter than receptacle, with cylindrical apex. Receptacle basally wider than apically. Posterior sclerotization of tignum spoon-shaped, wider than mid-section. Mid-section of tignum nearly straight. Anterior sclerotization of tignum narrower than mid-section. Apex of vaginal palpus subtriangular, with lateral margins slightly convex. Vaginal palpus narrowing from base till middle, thence slightly widening towards apex. Anterior sclerotization of vaginal palpus narrowed at apex and base, widened in middle. Anterior end of anterior sclerotization narrowly rounded. Anterior sclerotization wider than posterior.

Type: ♂ (Holotype, in IZCAS), 1) China: Yulong Mountain, Lijiang , Yunnan, alt. 2700m. 2) 1984.VII.21, leg. Shuyong Wang; 3) Holotype, Chaetocnema yulongensis sp. nov., Des. Ruan, Konstantinov & Yang, 2014.

Paratypes: 8♂ 10♀ ( IZCAS, 1♀ in USNM), China: Yulong Mountain, Lijiang , Yunnan, alt. 2700m, 1984.VII.21, leg. Shuyong Wang ; 2♂ 5♀ ( IZCAS, 1♂ in USNM), China, Gezan, Zhongdian , Yunnan, alt. 3150m, 1981.VIII.4, leg. Shuyong Wang ; 1♂ 5♀ ( IZCAS), China, Xiaozhongdian , Yunnan, alt. 2500–3200m, 1984.VIII.5, leg. Shuyong Wang ; 4♀ ( IZCAS, 1♀ in USNM), China, Lidiping, Weixi , Yunnan, alt. 3400m, 1984.VIII.13, leg. Shuyong Wang ; 1♂ ( IZCAS), China, Fengyi , Yunnan, alt. 2000m, 1955.VI.1, leg. B. Popov ; 2♂ ( IZCAS), China, Xiaguan , Yunnan, alt. 2050m, 1955.V.30, leg. B. Popov ; 6♂ ( SYSU), China, Kunming , Yunnan, alt. 1900m, 1940.VII.4, leg. J. L. Gressitt.

Remarks: C. yulongensis and C. deqinensis are extremely alike externally, but differ well in the shape of the aedeagus. In C. yulongensis , maximum curvature of the aedeagus in lateral view is situated medially; apical end of the aedeagus is narrowly rounded and the suprafrontal sulcus is obtuse in middle. In C. deqinensis , maximum curvature of the aedeagus is situated apically; the apex of aedeagus is broadly rounded and the suprafrontal sulcus is absent in the middle.

Figures

FIGURE 71. Chaetocnema yulongensis. A Male habitus (Holotype). B Prothorax, dorsal view. C Head, frontal view. D1–D2 Aedeagus, ventral view; D3 Aedeagus, lateral view. E Apex of Aedeagus, dorsal view. F Vaginal palpi. G Spermatheca. H Tignum.