Ctenoplus semialutaceus, Fuller & Platia, 2006

Fuller, E. & Platia, G., 2006, A revision of the click beetle genus Ctenoplus Candèze, 1863 (Coleoptera: Elateridae, Synaptina), Zootaxa 1217 (1), pp. 1-76 : 60-62

Ctenoplus semialutaceus n. sp.

Figures 28 , 40 , 45 , 80 , 111

Diagnosis

Medium­sized, uniformly dark brown Ctenoplus with a narrow band of alutaceous cuticle on the posterolateral margin of the hypomeron ( Fig. 45 ). C. alutaceus n. sp. also has alutaceous cuticle on the hypomeron, but C. alutaceus is smaller than C. semialutaceus (6.0– 6.5 mm vs. 9.0– 10.5 mm) and has a wider band of alutaceous cuticle ( Fig. 44 ).

Description Body uniformly dark brown dorsally, ventral surface of meso­ and metathorax and abdomen variably reddish­brown to brown; antennae, legs and palpi yellowish­brown; setae opaque light yellow. Length: 9.0– 10.5 mm; width 2.0– 2.5 mm.

Head. Punctures relatively large, shallow, almost contiguous throughout. Antennae ( Fig. 28 ) not reaching apex of pronotal hind angles by about length of antennomere 11; cuticle with dense minute punctures.

Prothorax. Pronotum ( Fig. 40 ): lateral margin varying from subparallel to slightly sinuate; lateral carina distinctly sinuate; punctures as on head, almost contiguous throughout; carina of hind angles sharp, slightly elevated, extending anteriorly slightly more than 1/3 length of pronotum in lateral aspect; posterior margin adjacent to scutellum sinuate. Hypomeron, Fig. 45 ; lateral margin with narrow band of alutaceous cuticle opposite procoxa, band about 1/4 width of hypomeron at level of procoxa; punctures as on head; mesal border with linear row of 6 punctures. Prosternum: punctures about 1/2 size of hypomeral punctures, almost contiguous throughout; prosternal spine: elongate, length to posterior concavity about 2X width immediately posterad procoxae, ventrolateral carinae joining slightly anterad apex.

Mesothorax. Scutellum flat, sloping slightly below level of adjacent elytra, anterior margin straight. Mesosternum posteriorly slightly raised above level of mesocoxae in lateral aspect, raised margin weakly concave, declivous beaded margin sloping at ca. 45°; posterior margin straight, slightly raised above metasternum. Mesepisternum glabrous on posterior 1/2; anterolateral groove punctate and setose. Elytra elongate but not attenuated, somewhat rounded apically, apices contiguous, each with or without a very small sutural tooth; striae weakly impressed; intervals moderately densely punctured; punctures in striae and on intervals separated by about own diameters; posterior margin of epipleura truncate.

Metathorax. Metasternum: carina posterad mesocoxa variable in length, up to 3X as long as basal width; punctures slightly smaller than hypomeral punctures, almost contiguous throughout.

Legs. Profemur with black microspines; claws robust, apical tine only slightly larger than subapical tines; tarsomere 4 with very small lobe.

Abdomen. Ventrite 5 about as long as basal width, subtriangular; dorsal submarginal carina broadly V­shaped; ventrites 1–5 closely punctured, punctures grading from subequal in size to those of metasternum laterally to about 1/2 that size along midline, almost contiguous throughout. Male genitalia, Fig. 80 ; parameres not enclosing median lobe ventrally, mesal margin of parameres sinuate ventrally. Female genitalia damaged; bursal plates subreniform, apparently symmetrical; tubular extension: proximal spines about same thickness and density as basal spines but shorter; distal spines larger, stouter, less dense, with large bases; other details unknown.

Material examined and range

2♂, 1♀. [ LAOS:] Holotype female, “ Laos, Vientiane, 30.iv.1965 "/ “ Native Collector , Bishop Mus.”[ BPBM] . Paratypes. 2♂, [ THAILAND:] “THAILAND bor. CHIANG DAO

env. 21.5– 4.6.1995, Lgt. SNIZEK M.” [ CPG]. This species is known from northern Thailand and western Laos ( Fig. 111 ), but see Discussion below .

Etymology

The species epithet is derived from ‘semi­’ + ‘alutaceus’, referring to a small patch of alutaceous cuticle on the hypomeron.

Natural history Adults have been collected between 30 April and 4 June.

Discussion

The males and female of the type series were not collected at the same time or place. Given the presence of externally indistinguishable species pairs in Ctenoplus , the association must be regarded as tentative.

Figures

FIGURE 111. Distribution of Ctenoplus species.

FIGURES 15–30. Antenna of Ctenoplus species. 15, C. javanensis Cand.; 16, C. sumatrensis n. sp.; 17, C. sanguinolentus (Cand.); 18, C. sanguinolentoides n. sp.; 19, C. nitidipennis Schwarz; 20, C. indicus n. sp.; 21, C. neosiamensis n. sp.; 22, C. siamensis n. sp.; 23, C. rufoantennatus n. sp.; 24, C. castaneus (Fleut.); 25, C. coomani Fleut.; 26, C. divergens n. sp.; 27, C. alutaceus n. sp.; 28, C. semialutaceus n. sp.; 29, C. cateianus n. sp.; 30, C. dorsalis n. sp. Scale bar = 0.5 mm.

FIGURES 31–43. Pronotal outline of Ctenoplus species, dorsal. 31, C. javanensis Cand.; 32, C. sumatrensis n. sp.; 33, C. sanguinolentoides n. sp.; 34, C. indicus n. sp.; 35, C. rufoantennatus n. sp.; 36, C. castaneus (Fleut.); 37, C. coomani Fleut.; 38, C. divergens n. sp., a: male, b: female; 39, C. alutaceus n. sp.; 40, C. semialutaceus n. sp.; 41, C. gigas n. sp.; 42, C. cateianus n. sp.; 43, C. dorsalis n. sp. Abbreviation: bf, sublateral longitudinal incision. Scale bar = 0.5 mm.

FIGURES 44–46. posterior part of hypomeron of Ctenoplus species. 44, C. alutaceus n. sp.; 45, C. semialutaceus n. sp.; 46, C. girardianus n. sp. 47, prosternum of C. nitidipennis Schwarz, ventral. 48, venter of mesothorax of C. dorsalis n. sp., ventral. 49, tarsus of C. castaneus (Fleut.), lateral. Abbreviations: ac, alutaceous cuticle; ag, anterior groove of mesepisternum; as, anterior articulating surface of mesosternum; c, mesocoxa; d, lateral depression of mesosternum; gr, groove on prosternum; l, lobe of tarsomere 4; lp, anterolateral projection of mesepimeron; mf, mesosternal cavity; pr, projection of mesal border of hypomeron. Scale bar = 44–46, 48, 49: 0.25 mm; 48: 0.5 mm.

FIGURES 66–85. Male genitalia of Ctenoplus species, dorsal aspect unless otherwise specified. 66, C. javanensis Cand.; 67, C. sumatrensis n. sp.; 68, C. sanguinolentoides n. sp.; 69, C. nitidipennis Schwarz; 70, C. indicus n. sp.; 71, C. collaris Cand., a, dorsal, b, ventral; 72, C. pseudocollaris n. sp.; 73, C. neosiamensis n. sp.; 74, C. siamensis n. sp.; 75, C. rufoantennatus n. sp.; 76, C. castaneus (Fleut.), a, dorsal, b, lateral; 77, C. coomani Fleut.; 78, C. divergens n. sp.; 79, C. alutaceus n. sp., a, dorsal, b, lateral; 80, C. semialutaceus n. sp.; 81, C. balli n. sp.; 82, C. girardianus n. sp.; 83, C. gigas n. sp.; 84, C. cateianus n. sp.; 85, C. deceptus n. sp. Abbreviations: st, median struts; pa, parameres; ph, phallobase. Scale bar = 0.25 mm.