A revision of the click beetle genus Ctenoplus Candèze, 1863 (Coleoptera: Elateridae, Synaptina) Author Fuller, E. Author Platia, G. text Zootaxa 2006 2006-05-26 1217 1 1 76 https://biotaxa.org/Zootaxa/article/view/zootaxa.1217.1.1 journal article 10.11646/zootaxa.1217.1.1 1175­5334 5064796 FECFEC7C-0DBF-45E5-AEB6-95B1943902AF Ctenoplus siamensis n. sp. Figures 22 , 63 , 74 , 109 Diagnosis Medium­sized, reddish­brown and black Ctenoplus with rounded apices of the elytra and a small ventral lobe on tarsomere 4. C. siamensis is similar in size and colour to C. rufoantennatus n. sp. , but males are slightly larger (8.0– 8.5 mm vs. 6.5–7.5 mm ) and C. siamensis lacks a well developed ventral lobe on tarsomere 4. The two species are also allopatric, C. siamensis living in Thailand and C. rufoantennatus in India . Description Generally as in C. collaris except as noted. Elytra reddish­brown, suffused with black in apical 1/2, setae brown; antennae indistinctly bicoloured: basal 3 articles brownish­yellow, articles 4–11 darker brown. Length: 8.0– 8.5 mm ; width: 2.0 mm. Head. Antenna, Fig. 22 ; male antennomeres 4–11 with fine moderately long, erect setae along anterior margin. Prothorax. Pronotal punctures on disk slightly larger and denser than most specimens of C. collaris examined. Hypomeron: inner angle of posterolateral angles varying from obtuse to vertical. Prosternal spine: ventrolateral carinae not extending anterad procoxal cavities, fusing near midpoint of spine in ventral aspect, carina visible to apex. Mesothorax. Scutellum flat. Mesepisternum varying from completely glabrous to bearing 7–9 punctures mesolaterally. Elytra slightly less narrowed in apical 1/2 than C. collaris , apex rounded ( Fig. 63 ), apices only very slightly dehiscent; striae shallowly impressed, most punctures connected by shallow groove, most punctures separated by slightly less than own diameters. Metathorax. Metasternum: punctures of uniform density and size throughout, separated by less than 1/2 own diameters. Legs. Claws with 6–7 subapical tines. Abdomen. Male genitalia, Fig. 74 . Female unknown. Variation. Three paratypes have the elytra, venter of meso­ and metathorax and abdomen more darkly pigmented than the other two specimens of the type series. Material examined and range 5♂ . [ THAILAND :] Holotype male: “NW THAILAND 19.19N 97.59E , Mae Hong Son , Ban Si Long , 1200m , 23– 31.5.1991 , L. Dembický leg.” [ NHMW ] . Paratypes : 2♂ same locality and date as holotype , but collected by J. Horak [ CPG , CSV ] ; 1♂ , “NW THAILAND 19.19N 97.59E , Mae Hong Son , Ban Huai Po , 1600–2000m , 17– 23.5.1991 , L. Dembický leg.”[ NHMW ] ; 1♂ , “THAILAND bor occ., 30.4.–14.5 1991, Mae Hong Son env., Ban Huai Po , 1800m , Jan Farkač leg.” [ ERFC ]. This species is known from northwest Thailand ( Fig. 109 ) . Etymology The species epithet is derived from ‘siam’ + ‘­ensis’, denoting from Siam ( Thailand ), the provenance of known specimens. Natural history The type series was collected between 1200 and 2000 m in elevation, and from 30 April to 31 May.