Coelostoma (Holocoelostoma) stultum ( Walker, 1858 )

Jia, Fenglong, Aston, Paul & Fikáček, Martin, 2014, Review of the Chinese species of the genus Coelostoma Brullé, 1835 (Coleoptera: Hydrophilidae: Sphaeridiinae), Zootaxa 3887 (3), pp. 354-376 : 370-371

Coelostoma (Holocoelostoma) stultum ( Walker, 1858)

( Figs. 11–12 , 32–33 )

Hydrobius stultum Walker, 1858: 209 .

Cyclonotum simplex Sharp, 1874: 419 .

Coelostoma sulcatum Pu, 1963: 77 . New synonym.

Type material examined: Coelostoma sulcatum : PARATYPE: male ( SYSU), “Jingdong / 1200m / 26.iv.1957 // A. Monchadskiy leg. (with Chinese and Russian labels // Coelostoma sulcata Pu // Paratype ”; female? IZCAS?“Xishuangbanna / Gannanba / 540m / 13.iv.1957 // Fuji Pu leg. (Chinese and Russian labels) // Coelostoma sulcata // IOZ(E) 220515; male with lost genitalia ( IZCAS), “Xishuangbanna / Gannanba / 540m / 13.iv.1957 // Fuji Pu leg. (Chinese and Russian labels) // Coelostoma sulcata // IQZ(E.) 220516.

Additional material examined. GUANGXI: 2 males, 3 females ( IZCAS), outside of gate of Shiwandashan Forest Park, 263 m, in light trap, 7.vii.2011, Keqing Song leg.; 54 spec., Yangshuo, viii.1984, Shoujian Chen leg.; 1 spec., same data as the former, but with a red label “ Holotype, Coelostoma guangxiensis , det. Wu Wu”; 1 male, same data as the former, but with a yellow label “ Paratype, Coelostoma guangxiensis , det. Wu Wu”; 1 female, same data as the former, but with a label “Allotype, Coelostoma guangxiensis , det. Wu Wu”;1 spec., Nanning, 22.vi.1958, Zhelong Pu leg.; 1 spec., same data as the former, but with a label “ Paratype, Coelostoma guangxiensis , det. Wu Wu”; 2 spec., same data as the former, but with a label “ Coelostoma guangxiensis ”; 4 spec., Nanning, 19.vi.1977, Zhihe Huang leg.; 1 spec., Jinxiu, Luoxiang, 400m, 16.v.1999, Mingyuan Gao leg.; 1 spec., Shangsi, Hongqi forestry farm, 300m, 29.v.1999, Xin Ke leg. GUANGDONG: 2 spec., Lianjiang, 25.ix.1985, Wu Wu leg.; 2 spec., Huaxian, Dabuling, 26.viii.1983, Zhihe Huang leg.; 2 spec., same data as the former, but with a label “ Paratype, Coelostoma guangxiensis , det. Wu Wu”; 1 spec., Ruyuan, Longxi, 4-5.x.1964, trapped in light; 2 spec., Zhuhai, Qi’ao Island, 12.vii.2005, Fenglong Jia leg.; 1 spec., Dinghushan Mount, 4.vi.1958, Cuiying Li leg.; 1 spec., Shenzhen, 8-11.viii.2006, Fenglong Jia leg.; 1 spec., rice field of Farm, Sun Yat-sen University, 25.iv.1935, with a label “ Coelostoma fabriciusi ”; 5 spec., Sihui, Dasha town, 5.vi.1998, Fenglong Jia leg.; 1 spec., Xinhui, viii.2001, Xiaoli Tong leg.; 1 spec., Fengkai, Heishiding Nature Reserve (in mud of a small pool), 13.viii.2010, Fenglong Jia leg.; 1 spec., Guangzhou, viii.1938, Zhelong Pu leg.; 1 spec., Guangzhou, Henan cattle farm, 10.x.1985, with label “Coel. sp. 2”; 2 spec., same locality as the former, but 25.vii.1985, each with a yellow label “ Paratype, Coelostoma xizangensis , det. Wu Wu”; 1 spec., the same data as the former, but with a label “ Coelostoma xizangensis ”. MACAU: 1 male, 1 female ( IZCAS), Ludancheng Ecological Natural Reserve, First district, 5.iv.2013, Fenglong Jia et Weicai Xie leg. YUNNAN: 3 spec. ( IZCAS, OZ (E)1381171, IOZ(E)1381172, IOZ(E)1381190), Xishuangbanna, Mengla, 620-650m, 25.v.1959, Yiran Zhang leg. 1 spec., Chengjiang, v.1949, with a label “ Coelostoma stultum ?”; 6 spec., Mengla Nature Reserve, 4-5.viii.2007, Jiahui Li leg.; 1 spec., Mangshi, 900m, 17.v.1955, Caiyun Zhou leg.; 1 male, Naban village Nabanhe Conserve, 1.vii.2004, Li & Tang leg.; 1 male, Xishuangbanna, Gannanba, 650m, 13.iii.1957, leg. Qiuzhen Liang (Chinese label and Russian label), with a label “ Coelostoma sulcata Pu ” (aedeagus dissected, but lost); 4 spec., Mengla, Wangtianshu Nature Reserve, light trap, 22.vii.2011, Li Yun leg.; 4 males ( ASHC, NME, NMPC): Dali Bai Pref., water reservoir 5 km SSW Dacang, 25°23ʹ35ʺN 100°11ʹ32ʺE, 1778 m, 17.ix.2009, D. W. Wrase leg.; 1 male, 5 spec. ( ASHC, NME, NMPC): Dali Bai Pref., NE bank of Er Hai, 27 km N Dali, 25°57ʹN 100°09ʹE, 1980 m, under plants/litter, 12.vi.2007, D. W. Wrase leg.; 4 males ( NME, coll. Weigel, 1 NMPC): Yishuangbanna, 20 km NW Jinghong, Man Dian vicinity, at light, 22°08ʹN 100°40ʹE, 740 m, 27.vi.2009, A. Weigel leg.; 5 males ( NME, ASHC): same locality, 26.v.2008, A. Weigel leg.; 1 male (Weigel): same locality, 23.v.2008, A. Weigel leg.; 1 male (Weigel): Yishuangbanna, 23 km NW Jinghong, Na Ban VIII., 22°10ʹ04ʺN 100°39ʹ52ʺE, 680 m, 5.vi.2008, A. Weigel leg. HUNAN: 2 spec., Yizhang, 16.iii.1941, Zhelong Pu leg., each with a label “ Coelostoma stultum ”. JIANGXI: 2 spec., Nanchang, ix.1956; 3 spec., Jiujiang, Duchang County, Linshan village, 15-20.viii.2010, Yan Mei leg.; 1 spec. ( IZCAS), Jiulianshan, Huangniushi vegetable field, 26.vi.1975, Youwei Zhang leg.; 1 spec. ( IZCAS), Longnan, Jiulianshan, Daqiutian, 14.vi.1975,. Youwei Zhang leg.; 1 spec. ( IZCAS), Longnan, Jiulianshan, 8.vi.1975, in light, Youwei Zhang leg. FUJIAN: 1 spec., Nanjing, Hexi town (edge of a pool), 13.vii.2010, Fenglong Jia leg.; 1 spec., Fu’an, x.1963, Shanxiang Lin leg. XIZANG: 2 spec., Motuo, Beibeng, 850m, 25.v.1983, Yinheng Han leg., each with a yellow label “ Paratype, Coelostoma xizangensis , det. Wu Wu”; 1 male, same data as the former, but with a red label “ Holotype, Coelostoma xizangensis , det. Wu Wu”; 1 female, same data as the former, but with a label “Allotype, Coelostoma xizangensis , det. Wu Wu”; 2 spec., same data as the former, but with a label “ Coelostoma xizangensis ”. SICHUAN: 1 spec., Ya’an, Yucheng district, Taohua mount (edge of pool), 30.vii.2010, Jia Wang leg. CHONGQING: 1 spec., Jinfoshan (Nanchuan county), 19.vi.1945, with a label “ Coelostoma stultum ?, ident. C.L. Pu” and another label “ Coelostoma stultum ”; 1 spec., Paganian, Luzon (? locality), with 3 labels “ Coelostoma stultum ”. HONG KONG ( PCPA, 2 spec.): 1 male, 22.ii.2009, Wang Tong, in light trap, Paul Aston leg.; 1 male, 19.vi.2012, Wang Tong, in light trap, Paul Aston leg.

Diagnosis. Body length 4.2–5.8 mm. Prosternum moderately convex medially, not carinate, without anteromedian finger-shaped process. Head, pronotum and elytra with similar punctation; elytra with lateral portion more or less strongly punctate, without traces of series of punctures laterally. Mesofemora without dense pubescence, but with punctures bearing strong setae ( Fig. 11 ). First abdominal ventrite not carinate, fifth ventrite emarginate and with a row of stout setae apically ( Fig. 12 ). Aedeagus ( Figs 32-33 ): 0.85 mm long. Median lobe broad and subparallel, tongue-shaped apically, gonopore situated at apex; parameres longer and much narrower than median lobe, outer edge broad curved subapically.

Remarks. Pu (1963) described Coelostoma sulcatum as a new species from Sisongpanna (=Xishuangbanna, type locality) and Chingtung (Jingdong) in Yunnan Province, China. He also recorded this species from Xizang ( Pu 1988). The senior author examined two paratypes of this species deposited in IZCAS, of which one is female and the genitalia of second is lost. Externally, both specimens correspond well with C. stultum , including the apically emarginate last abdominal ventrite and slightly convex prosternum protruding anteriorly. The senior author was lucky to check a male paratype from Jingdong and 5 specimens with label data corresponding to those listed by Pu (1988) for the specimens of C. sulcata recorded by him from Xizang, all deposited in SYSU. We have also examined specimens recently collected at the type locality (Xishuangbanna), all of them corresponding to the original description of C. sulcatum and at the same time to C. stultum . After a careful study of all these specimens, we are sure that C. sulcatum is a junior synonym of C. stultum .

Distribution. China (Fujian, Guangxi, Guangdong, Jiangxi, Sichuan, Taiwan, Yunnan, Xizang), Andaman Is., Burma, India, Indonesia, Japan, Malaysia, Mascarene Is., Nicobar Is., Oman, Philippines, Saudi Arabia (south), South Korea, Sri Lanka, Thailand, United Arab Emirates, Vietnam. ( Hansen 1999, Fikáček et al. 2010)

Figures

FIGURES 9 – 14. Characters distinguishing the subgenera of Coelostoma occurring in China. 9 – 10: subgenus Lachnocoelostoma (C. bifidum sp. nov.); 11 – 12: subgenus Holocoelostoma (C. stultum); 13 – 14: subgenus Coelostoma s. str. (C. orbiculare). 9, 11, 13: mesofemur in ventral view; 10, 12, 14: posterior margin of andominal ventrite 5.

FIGURES 32 – 33. Aedeagus of Coelostoma stultum. 32: from Guangdong, 33: specimen from Xizang identified as C. sulcatum by Pu (1988).