Chaetocnema (Chaetocnema) yaosanica Chen, 1939

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 : 119-121

47. Chaetocnema (Chaetocnema) yaosanica Chen, 1939

( Fig. 69 )

Chaetocnema yaosanica Chen, 1939: 31 . TL: China, Guangxi. TD: IZCAS.

Distribution: China (Fujian, Guangxi, Yunnan), Malaysia.

Host plants: Unknown.

Description: Body length 1.50–1.75 mm; width 0.75–0.95 mm. Ratio of elytron length at suture to maximum width, 2.10–2.20. Ratio of pronotum width at base to length at middle, 1.60–1.70. Ratio of length of elytron at suture to length of pronotum at middle, 2.50–2.55. Ratio of width of both elytra at base to width of pronotum at base, 1.10–1.16. Ratio of maximum width of both elytra to maximum width of pronotum, 1.35–1.45.

Dorsum shiny black, almost without metallic luster. Antennomeres 1–6 completely yellow, 7-11 yellow brown. Pro- and mesolegs, hind tibia and tarsi completely yellow. Metafemur dark brown.

Head hypognathous. Frontal ridge narrow and convex. Frontolateral sulcus present. Suprafrontal sulcus shallow and faint, obcordate. Ratio of width of frontal ridge between outer ridge of antennal sockets to width of antennal socket, 1.20–1.25. Frons with numerous relatively long setae situated on punctures near fronto-lateral sulcis, which is similar to those in C. warchalowski and C. resplendens . Vertex flat, situated on same level as orbit, without punc- tures, except 2–3 on each side near eye.

Base of pronotum without longitudinal impressions. A deep row of large punctures present along basal margin of pronotum. Pronotal base slightly expanded in middle. Elytron with scutellar row of punctures single and regular. Second to eleventh rows of punctures regular at base of elytron. Humeral callus well-developed.

Large lateral denticle on metatibia obtuse. Metatibial serration proximal to large lateral denticle absent.

Apex of aedeagus in ventral view narrowing gradually, truncate. Ventral longitudinal groove of aedeagus absent or poorly developed. Apical denticle of aedeagus in ventral view long, flattened on top. Apex of aedaeagus slightly curved ventrally in lateral view. Minute, transverse wrinkles on ventral side of aedeagus absent. Aedeagus in lateral view nearly straight at base and middle, slightly curved ventrally at apex.

Spermathecal pump much shorter than receptacle, with apex flattened. Spermathecal receptacle longer than wide, barrel shaped, weakly sinuate. Receptacle widest near base. Base of receptacle narrower than apex. Apex of vaginal palpus evenly rounded. Vaginal palpus narrowing from base till middle, thence slightly widening towards apex. Anterior sclerotization of vaginal palpus slightly widening anteriorly. Anterior end of anterior sclerotization broadly rounded. Posterior sclerotization longer than wide. Posterior sclerotization about as wide as anterior.

Type: 1♀ (Holotype, in IZCAS): 1) China, Yaosan, Guangxi. 2) Chaetocnema yaosanica . 3) Holotype. 4) Chaetocnema yaosanica sp. nov. Sicien Chen.

Material: 1♂ ( IZCAS), China, Fujian, Huangkeng , 3.VII.1980, leg. Bangkan Huang ; 1♂ ( IZCAS), China, Fujian, Huangkeng, Dazhulan to Xianfengling , 28.V.1960, alt. 950–1170m, leg. Yong Zuo ; 3♂ 6♀ ( IZCAS), China, Fujian, Chong An, Xingcun , 4.V.1960, alt. 1170m, leg. Yong Zuo ; 1♂ 2♀ ( IZCAS), China, Fujian, Dazhulan, 15–20.VI.1948; 15 ( IZCAS), China, Fujian, Wuyishan, Guanping , IZCAS, 1997.VII.28, Chaetocnema yaosanica Chen det. Shuyong Wang ; 72 specimens ( IZCAS), China, Fujian, Dazhulan , 15–20.VI.1948, IZCAS, Chaetocnema yaosanica Chen ; 5 specimens ( IZCAS), China, Fujian, 15.IV.1948, IZCAS, Chaetocnema yaosanica Chen det S.H. Chen ; 1♂ ( IZCAS), China, Guangxi, Huaping, Anjiaping , 1.VIII.2006, leg. Meiying Lin ; 1♀ ( IZCAS), China, Yunnan, Mengla , 20.IV. 1982, leg. Shengqiao Jiang ; 1♀ ( USNM), Malaysia, Banguey , b. Borneo, Ch. sticta Motch .

Remarks: This species closely resembles C. warchalowskii in the punctation on frons near clypeus and they can be differentiated by differences of punctures on pronotum and shape of aedeagus. This species also resembles C. resplendens that has narrower body, darker color and round punctures on frons (punctures on frons somewhat rugged in C. yaosanica ).

Figures

FIGURE 69. Chaetocnema yaosanica. A Male habitus. B Pronotum. C Head, frontal view. D Aedeagus, ventral view. E Aedeagus, lateral view. F Apex of aedeagus, ventral view. G Vaginal palpi. H Spermatheca. I Pygidium (tergite 7) of female. J Head, frontal view.