Coelostoma (Lachnocoelostoma) vagum Orchymont, 1940 (Fig. 30) Coelostoma vagum Orchymont, 1940: 159. Type material examined: Coelostoma vagum: PARATYPE: " Laos / (Vitalis) // A. dʹOrchymont det. 1922 / Coelostoma / transcaspicum Reitt. // Para- / type ” [the specimen lacks identification label, but was placed among other paratypes of C.vagum in the Orchymont collection and is clearly sonspecific with them]. Material examined.? ANHUI: 1 spec., Woo-Fu SSU (?Wuhu), 11.v.1932, with a label “ Coelostoma vagum Orchym, det. C.L. Pu, 1961”. SHANDONG: 1 spec., Tai-an, with a label “ Coelostoma vagum Orchym, det. C.L. Pu, 1961”. YUNNAN: 1 male (IZCAS), Menglun, 11.iv.1982, leg Subai Liao; 1 spec., Mengla Nature Reserve, 4- 5.viii.2007, Jiahui Li leg.; 4 spec., Jingdong, 1170m, 15.iii.1957, let. Guangji Hong, et. al., each with a label “ Coelostoma vagum Orchym, det. C.L. Pu, 1961”; 8 spec., same data as the former, but 26.iv.1957, 1200m; 1 spec., 22 km north to Jingdong, 12.v.1957, with a label “ Coelostoma vagum Orchym, det. C.L. Pu, 1961”; 1 spec., Suburb of Dali, 2100m, 30.iv.1955, Yang Zhao leg., with a label “ Coelostoma vagum Orchym, det. C.L. Pu, 1961”; 2 spec., Xishuangbanna, Gannanba, 650m, 13.iii.1957, Fuji Pu leg., with a label “ Coelostoma vagum Orchym, det. C.L. Pu, 1961”; 1 spec., same data as the former, but Qiuzhen Liang leg.; 1 male, 1 female (IZCAS), Manfei, Nabanhe Conv. 10.I. 2004, Li & Tang leg.. Diagnosis. Body size 4.9–5.6 mm. Prosternum moderately convex medially, not carinate, with anteromedian tooth. Head, pronotum and elytra with similar punctation; elytra with lateral portion more or less strongly punctate, without traces of series of punctures laterally. Mesofemora densely pubescent, except at extreme apex. First abdominal ventrite not carinate, fifth ventrite emarginate and with a row of stout setae apically. Aedeagus (Fig. 30): 1.7 mm long. Median lobe much shorter than parameres, strongly narrowing near apex, pointed apically, gonopore narrow, situated subapically; parameres relatively slender, with inner face almost straight. Distribution. China (?Anhui, Shandong, Yunnan), Cambodia, Indonesia, Malaysia, Laos, Vietnam. (Hansen 1999).

Published as part of Jia, Fenglong, Aston, Paul & Fikáček, Martin, 2014, Review of the Chinese species of the genus Coelostoma Brullé, 1835 (Coleoptera: Hydrophilidae: Sphaeridiinae), pp. 354-376 in Zootaxa 3887 (3) on page 370, DOI: 10.11646/zootaxa.3887.3.4, http://zenodo.org/record/227166