Chaetocnema (Chaetocnema) fortecostata 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 : 49-53

12. Chaetocnema (Chaetocnema) fortecostata Chen, 1939

( Fig. 31 )

Chaetocnema fortecostata Chen, 1939: 33 . TL: China, Yunnan. TD: IZCAS.

Distribution: China (Shaanxi, Zhejiang, Hubei, Jiangxi, Hunan, Fujian, Taiwan, Guangxi, Chongqing, Sichuan, Yunnan); Japan, India.

Host plants: Polygonum sp. ( Polygonaceae ) (Ruan et al., 2014).

Description: Male body length: 1.75–1.90 mm. Female body length: 2.03–2.12 mm. Male body width: 0.95– 1.08 mm. Ratio of length of antenna to length of body: 0.64±0.05. Ratio of elytral length (along suture) to width (maximum): 2.64±0.05. Ratio of pronotum width (at base) to length: 1.62±0.05. Ratio of length of elytron to length of pronotum (along middle): 2.98±0.05. Ratio of width of elytra at base to width of pronotum at base (in middle of humeral calli): 1.07–1.19. Ratio of maximum width of elytra to maximum width of pronotum: 1.34±0.05.

Dorsum, including head, entirely bronzy. Antennomere 1 partially dark brown, 2–3 yellow, 4 yellow or partly brown, 5 partially brown, 6-11 black. Pro- and mesofemora brown with yellow apex. Metafemora brown. All tarsomeres brown with yellow basally.

Head hypognathous. Frontal ridge between antennal sockets narrow and convex. Frontolateral sulcus present. Suprafrontal sulcus shallow and faint or deep laterally, shallow in middle. Suprafrontal sulcus slightly concave. Orbital sulcus (above antennal socket) obscure and narrow. Ratio of width of frontal ridge to width of antennal socket: 0.56–0.66. Ratio of width of orbital sulcus to width of frontolateral sulcus: 0.71±0.05. Surface of vertex sparsely and unevenly covered with 5–6 punctures near each eye. Number of punctures on orbit: 1–2 on each side. Number of setae along frontolateral sulcus: 5–6 on each side. Number of setae on frons (triangular area surrounded by frontolateral sulcus and clypeus): 0. Number of setae on clypeus: 5. Number of setae on labrum: 6. Anterior margin of labrum slightly convex in middle.

Base of pronotum with two short, obscure longitudinal impressions, without punctures near basal margin. Deep row of large punctures at base of pronotum present laterally, absent in middle. Basal margin of pronotum evenly convex. Lateral margins of pronotum slightly convex with maximum width near base. Anterolateral prothoracic callosity longer than wide, protruding laterally, with evenly curved outer margin. Posterolateral prothoracic callosity reaching up to lateral margin of pronotum. Diameter of pronotal punctures 2 to 4 times smaller than distance between adjacent punctures.

Elytra with convex sides. Scutellar row of punctures regular and single. Remaining rows regular. Humeral calli well developed. Interspaces smooth and glabrous. Two rows of minute punctures present on each interspace.

First male protarsomere, length to width ratio: 1.65±0.05. First and second male protarsomeres, length to length ratio: 1.94–2.24, width to width ratio: 1.42–1.45. First male protarsomere, ratio of width at apex to width at base: 1.60–1.75. Large lateral denticle on metatibia sharp. Metatibial serration proximal to large lateral denticle present, obtuse. Metatibia proximad to denticle in dorsal view concave. First male metatarsomere, length to width ratio: 3.60–3.67. First and second male metatarsomeres, length to length ratio: 1.87–1.93, width to width ratio: 0.83. Third and fourth male metatarsomeres, length to length ratio: 0.60–0.65. Ratio of metatibia length to metafemora length: 0.76±0.05. Ratio of length of hind leg to length of body: 0.87±0.05.

Aedeagus robust and thick in lateral view. Apical third of aedeagus widening evenly in ventral view, thence narrowing abruptly towards apex. Ventral longitudinal groove of aedeagus absent towards apex, poorly developed in middle and basal part. Apical denticle of aedeagus in ventral view poorly differentiated, curved ventrally in lateral view. Minute transverse wrinkles on ventral side of aedeagus absent. Aedeagus in lateral view slightly sinuous near apex. Maximum curvature of aedeagus in lateral view situated medially. Ratio of width (in middle) to length of aedeagus (in ventral view) about: 0.146.

Spermathecal receptacle oblong. Spermathecal duct straight. Spermathecal pump much shorter than receptacle with cylindrical apex. Maximum width of receptacle situated basally. Receptacle basally wider than apically. Posterior sclerotization of tignum spoon-shaped, wider than mid-section. Anterior sclerotization of tignum narrower than mid-section. Apex of vaginal palpus subtriangular, with gently convex lateral margin. Vaginal palpus (before apex) narrowing from base till middle, thence widening towards apex. Anterior sclerotization of vaginal palpus slightly widening anteriorly, slightly and evenly curved along length. Anterior end of anterior sclerotization broadly rounded. Length of posterior sclerotization greater than width. Posterior sclerotization about as wide as anterior.

Types: Lectotype of Chaetocnema fortecostata : 1♂, 1) Yangshuo, 21.VIII.1938, 2) Lectotype, Chaetocnema fortecostata Chen, 1939 , des. Yongying Ruan et al., 2014.

Paralectotypes of Chaetocnema fortecostata : 2♂ 5♀, 1) Yangshuo, 21.VIII.1938, 2) Paralectotype, Chaetocnema fortecostata Chen, 1939 , des. Yongying Ruan et al., 2014.

Paratypes of Chaetocnema kimotoi : Paratype female: 1) Korea, Kum–gang san, 3–4 km S, Hotel Kum–gang, 12.VII.1977, 2) No. 363—netting in grasses, Dely & Draskovits, 3 ) Paratype (1 USNM) ; Paratype female: 1) Korea, Sa Gam. 30–40 km N Pyongyan environs water–basin, 24.VII.1977, 2) No. 384—netting in grasses, Dely & Draskovits, 3 ) Paratype, 4) Chaetocnema kimotoi m., det. B. Gruev (1 USNM) ; Paratype. 1) Korea, Kum–gang san, 3–4 km S, Hotel Kum–gang, 12.VII.1977, 2) No. 363—netting in grasses, Dely & Draskovits, 3 ) Paratype (1 USNM) .

Lectotype and Paralectotype of Chaetocnema granulosa : 1 male (BMNH): 1) Japan, 2) Type, 3) Type, H.T., 4) Baly Coll., 5) Chaetocnema granulosa Baly , Nagasaki; 6) Lectotype Chaetocnema granulosa Baly des. A. S. Konstantinov et al. 2009; Paralectotype (1 BMNH): 1) Baly Coll.; 2) Plectroscelis granulosa Bal Japan; 3) Paralectotype Chaetocnema granulosa Baly des. A. S. Konstantinov et al. 2009.

Material: 19♀ 14♂ ( IZCAS), China, Huoditang, Qinling Mountain , Shaanxi, alt. 1600m, 6.VI.2013, leg. Yongying Ruan , feed on Polygonum sp.; 3, Maoping, Yangxian, Qinling Mountain , Shaanxi, alt. 701m, 10.VI.2013, leg. Yongying Ruan ; 2♂ ( IZCAS), China, Longmen River, Xingshan , Hubei, alt. 1300m, leg. Shimei Song ; 6, Longmen River, Xingshan , Hubei, 8.IX.1994, alt. 1300m, leg. Jian Yao , feed on Polygonum sp.; 1♀ 2♂ ( IZCAS), China, Sanxia Linchang, Badong , Hubei, 26.VI.1994, alt. 130m, leg. Jian Yao ; 2♀ 1♂ ( IZCAS), China, Beibei , Chongqing, 17.V.1941 ; 3♂ ( IZCAS), China, Longchi , Sichuan, IX.29 ; 1♀ 2♂ ( IZCAS), China, Fengdu , Sichuan, alt. 200m, 29.IX.1994, leg. Shimei Song ; 56, Wangerbao, Wanxian , Sichuan, alt. 1200m, 4.X.1994, leg. Jian Yao ; 1♀ 1♂ ( IZCAS), China, Chudian, Emei Mountain , Sichuan, 28.VI.1957, leg. Fuxing Zhu ; 1♀ ( IZCAS), China, Tienmu Shan , Zhejiang, 20.IX.1953; 24, Shanmuhe, Hunan, alt. 600, 14.VIII.1988, leg. Shuyong Wang ; 7♀ 4♂ (IZ- CAS), China, Xingzi, Jiangxi, 1932 ; 1♀ 1♂ ( IZCAS), China, Shuyang, Fuan , Fujian, IV.2013, leg. Yongying Ruan , feed on Polygonum sp.; 5♀ 2♂ ( IZCAS), China, Sangxiang, Xingcun, Chongan , Fujian, alt. 740m, 7.VI.1960, leg. Yong Zuo ; 31 ( USNM), China, Fujian, Dayushan Island , 4.VI. 2014, 443 m, leg. A. Konstantinov ; 18 ( USNM), China, Fujian, env. of Fuan , 03.VI.2014, 1088 m, leg. A. Konstantinov ; 73 ( USNM), China, Wuyi Mountain , Fujian, 31.V.2014, leg. A. Konstantinov ; 23 ( USNM), China, Youxi City , Fujian, 179–197 m, 30.V.2014, leg. A. Konstantinov ; 187, Baijixun, Weixi , Yunnan, alt. 1780m, leg. Shuyong Wang , feed on Polygonum sp.; 14♀ 3♂ ( IZCAS), China, Xiaomengyang , Yunnan, alt. 900m, III–IV.1957, leg. Shuyong Wang ; 1♂ ( IZCAS), Damenglong, Xishuangbanna , Yunnan, alt. 650m, 6.X.1958, leg. Zhizhi Chen ; 3♀ 1♂ ( BMNH), Tsur I., Holst., 98–214 ; 1♂ 2♀ ( USNM), India, Assam, 10mile N Tinsukia , in jungle, 29.III.1944, D. E. Hardy ; 4♂ 13♀ ( USNM); Japan, Mitsukuri , 25–IX–1924 .

Remarks: C. fortecostata is similar to C. picipes and C. cheni . It can be separated from the latter two species by the following characters: the aedeagus in lateral view is robust in C. fortecostata and slender in both C. picipes and C. cheni ; dorsum is bronzy in C. fortecostata , while the same in C. picipes and C. cheni are coppery.

Figures

FIGURE 31. Chaetocnema fortecostata. A Male habitus. B Pronotum. C Head. D Aedeagus, ventral and lateral view. E Apex of Aedeagus, dorsal view. F Vaginal palpi. G Spermatheca. H Tignum.