Coelostoma (Lachnocoelostoma) coomani Orchymont, 1932

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 : 366

Coelostoma (Lachnocoelostoma) coomani Orchymont, 1932

( Fig. 24 )

Coelostoma (s.str.) Coomani Orchymont, 1932 : 668.

Coelostoma (Lachnocoelostoma) coomani: Mouchamps (1958: 33) .

Type material examined. PARATYPE: 1 male ( IRSNB): ‟LACTHO / Tonkin / de Cooman // Para / type ” [the specimen lacks identification label, but was placed among other paratypes of C. coomani in the Orchymont collection and is clearly conspecific with them].

Additional material examined: GUANGXI: 11 spec. ( SYSU): Shiwandashan Forest Park, light trap, 263 m, 7.vii.2011, Song Keqing leg.; 3 spec. ( IZCAS), same data as the former; 12 spec. ( SYSU): Shiwandashan Forest Park, 339 m, edge of upper river, 19.vii.2011, Song Keqing leg.; 4 spec. ( IZCAS): same data as the former ( IZCAS); 13 males, 29 females. 42 spec. ( NMPC): Shiwandashan National Forest Park, tourist centre, 28.8 km SSW of Shangsi, 21°54.3ʼN 107°54.2ʼE, 280 m, on wet concrete next to the artificial drain + on wet stones of the waterfall behind the hotel in the tourist centre [MF03], 5-9.iv.2013, Fikáček, Hájek & Růžička leg.; 8 spec. ( NMPC): same locality, but exposed stony bank of a small river with isolated puddles + drains + wet rock partly overgrown with algae. YUNNAN: 1 male ( SYSU): Naban village Nabanhe Conserve, 1.vii.2004, Li & Tang leg.; 1 male ( SYSU): Banna Botanical Garden, 567m, light trap, N21.92262°, E 101.27710°, Song Keqing leg.

Diagnosis. Body size 4.4–5.0 mm. Prosternum strongly carinate medially, with a strong dentiform process anteromedially. 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 with distinct median carina on basal two-thirds; last ventrite emarginate and with a row of stout setae apically. Aedeagus ( Fig. 24 ): 0.95 mm long. Median lobe slightly emarginated apically, gonopore at apical two-fifths; parameres slightly longer than median lobe, truncate at apex, continually curved on outer face.

Biology. We collected this species at night in hygropetric habitats (on wet stones in a small waterfall or on wet concrete next to drains) as well as on the edge of a river; few specimens were also attracted to a light trap.

Remarks. Mouchamps (1958) described C. coomani javanicum Mouchams, 1958 from Java. Based on the original description and figure of aedeagus, parameres of this subspecies are sharply projecting inwards apically and are much longer than the median lobe. Based on these differences, it seems probable that C. coomani javanicum represent a separate species rather than a subspecies of C. coomani

Distribution. China (Guangxi, Yunnan), Vietnam, Indonesia (Sumatra?, Java?). ( Hansen 1999, Orchymont 1932). First record from China.

Figures

FIGURES 24 – 31. Aedeagus of Chinese Coelostoma and related species. 24: C. coomani, 25: C. gentilii sp. nov., 26: C. phallicum, 27: C. huangi sp. nov., 28: C. martensi (paratype from Nepal), 29: C. wui, 30: C. vagum, 31: C. horni from southern Yunnan: Xishuangbanna).