Ctenoplus divergens, 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 : 56-58

Ctenoplus divergens n. sp.

Figures 14 , 26 , 38 , 55 , 78 , 100 , 110

Diagnosis

Small to medium­sized, uniformly brown Ctenoplus with divergent pronotal hind angles in males and most females; male genitalia as in Fig. 78 ; female genitalia as in Fig. 100. C . divergens is similar to C. coomani Fleutiaux but can be distinguished by the divergent hind angles of the pronotum in the male ( Fig. 38a , but see Variation below) and the sinuate lateral margins of the median lobe ( Fig. 78 ). In males of C. coomani , the hind angles are subparallel ( Fig. 37 ) and the lateral margins of the median lobe are straighter ( Fig. 77 ). Females of these two species can be distinguished by the length of the tubular extension, which is shorter in C. divergens than in C. coomani (c.f., Figs. 98, 100 ). In addition, C. divergens is known only from northern Thailand and Myanmar, while C. coomani is known only from Vietnam.

Description

Head, pronotum and ventral surface brown; elytra, antennae, palpi and legs yellowishbrown; setae whitish­yellow. Length: 6.0–10.0 mm; width: 1.0–2.0 mm.

Head, Fig. 14 ; supra­antennal carina obliterated at level of anterior tentorial pits in holotype, curving ventrally to meet anterior margin in paratypes; setae slightly longer than antennomeres 2+3. Eyes in dorsal aspect protuberant ( Fig. 14 ), but not protruding laterad anterolateral angle of pronotum. Antenna, Fig. 26 ; extending less than length of antennomere 11 posterad apex of pronotal hind angles; punctures about 1/2 size of frontal punctures, almost contiguous, longest setae slightly shorter than frontal setae, directed distally; male antennomeres 4–11 with fine, moderately long, erect setae along anterior margin; cuticle of antennomeres 2–11 microrugose.

Prothorax. Pronotum ( Figs. 38a, b ): hind angles variably divergent; punctures in male grading from coarse, simple and almost contiguous anteriorly to minute posteriorly along midline and separated by about 2X own diameter; in female, punctures coarse throughout and only slightly more separated posteriorly than anteriorly; setae same length as frontal setae. Hypomeron: impunctate mesal border with lateral projection adjacent to procoxae, projection subtriangular, apex broadly rounded; setae same length as pronotal setae; punctures shallow, simple, subequal to pronotal punctures in size, separated by about own diameters. Prosternum: punctures grading from subequal in size to hypomeral punctures anteriorly to minute between procoxae, separated by about 1/2 own diameters anteriorly grading to about 2X own diameters posteriorly; setae same length as hypomeral setae, anterior and mesal setae directed posteriorly, posterolateral setae directed mesally; prosternal spine ( Fig. 55 ): ventrolateral carinae extending onto prosternum to level of anterior margin of procoxal cavity, anterior extensions subparallel, carinae convergent posteriorly and fused for posterior 1/4 of ventral surface; dorsal margin about 1/3 again as long as ventral margin; spine between ventrolateral carinae punctate, punctures same size as posterior prosternal punctures, separated by about own diameters anteriorly, almost contiguous posteriorly.

Mesothorax. Scutellum flat, slightly longer than anterior width; anterior margin slightly produced, with transverse microstriae; setae as on pronotum; punctures minute, separated by 2–3X own diameters. Mesosternum between mesocoxae moderately thickened, posterior margin between mesocoxae not darkly pigmented in ventral aspect, lateral margins between mesocoxae slightly divergent; punctures subequal in size to middle prosternal punctures, separated by about own diameters; setae same length as prosternal setae, directed posteriorly. Mesepisternum almost glabrous with up to 12 setae. Elytra about 4X as long as basal width, lateral margins convergent apically; apex rounded, without sutural tooth; striae impressed in basal 1/4, grading into rows of punctures in apical 3/4, margins of impressed striae sharp; punctures circular, relatively deep, steepsided, separated by about 1/2 own diameters, without setae; intervals microrugose, punctures minute, separated by 2–3X own diameters.

Metathorax. Metasternum: projection posterad mesocoxa very short, present only as small rounded bump on ridge; punctures minute throughout, separated by 1–2X own diameters.

Legs. Shorter than other species; tarsomere 4 with very small lobe ventrally; claws with 6–8 subapical tines, longest only slightly shorter than apical tine, most about 3/4 length of apical tine, shortest about 1/3 length of apical tine, base of claw thick.

Abdomen. Terga lightly sclerotized, spiracles partially enclosed on terga 2–7; dorsal submarginal carina on ventrite 5 broadly V­shaped and less heavily sclerotized at apex; punctures along midline on ventrites 1–4 like metasternum, grading to larger, shallower, simple punctures laterally; setae as on metasternum. Male genitalia, Fig. 78 ; parameres separated ventrally by about width of median lobe, apex of parameres bluntly pointed; apex of median lobe nipple­like. Female genitalia, Fig. 100 ; spermatophore present in specimen illustrated, coiling of tubular extension lost; tubular extension: short, closely coiled with 3–4 coils then abruptly narrowed and recurved down through center of coils, coils increasing in width distally, recurved section straight and thin; with single sparse row of spines in proximal 2–3 coils; distal coil with broad patch of spines along distal end, spines about same density as more proximal coils, spines thorn­like, bases conspicuous.

Variation. The hind angles of the pronotum are divergent in most specimens of both sexes, but more conspicuously divergent in some specimens of both sexes. In side by side comparison, the hind angles are more divergent than those of C. coomani , but some specimens may be difficult to distinguish without having both species for comparison.

The sinuosity of the lateral margin of the median lobe varies from barely perceptible to as sinuous as illustrated ( Fig. 78 ). In the female, both the density of spines on the tubular extension and the number of non­marginal spines on the bursal plates are variable.

Material examined and range

6♂, 3♀. [ THAILAND:] holotype male, “NW THAILAND, Mae Hong Son, Ban Haui Po , 1600–2000m; 19.19N 97.59E, 17.­ 23.5.1991; L. Dembický leg” [ NHMW]. Allotype female, same data as holotype [ CPG]. Paratypes : 1♂, same data as holotype except “ J. Horák leg.”[ CCW] ; 2♂, “NE [sic] THAILAND 1–15. [sic]1991, Mae Hong Son, Ban Huai Po, 800–1600 m, S. Bíly ” [ CCW]; [ MYANMAR] 2♂, 2♀, “BURMA SW Shan State, Taunggyi , 1–18.vi.1997, J. Kalib. leg” [ CCW, ERFC]. This species has been found in northwestern Thailand and northeastern Myanmar ( Fig. 110 ) .

Etymology The species epithet refers to the divergent pronotal hind angles.

Natural history

Adults have been collected between 17 May and 18 June, at elevations between 800 and 2000m.

Figures

FIGURE 110. Distribution of Ctenoplus species.

FIGURES 11–14. Head capsule of Ctenoplus species, dorsal. 11, C. collaris Cand.; 12, C. pseudocollaris n. sp.; 13, C. dorsalis n. sp.; 14, C. divergens n. sp. Scale bar = 0.25 mm.

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 50–57. Prosternal spine of Ctenoplus and Silesis species. 50–57, lateral; 58, 59, ventral. 50, C. sanguinolentus (Cand.); 51, C. sanguinolentoides n. sp.; 52a, b, C. coomani Fleut.; 53, C. balli n. sp.; 54, C. gigas n. sp.; 55, C. divergens n. sp.; 56, C. alutaceus n. sp.; 57, C. dorsalis n. sp.; 58, C. brunneus Fleut.; 59, S. fulvus Fleut.; Abbreviations: da, dorsal apex; va, ventral apex. Scale bar = 0.25 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.

FIGURES 98–106. Female genitalia of Ctenoplus species. 98, C. coomani Fleut.; 99, C. brunneus Fleut.; 100, C. divergens n. sp.; 101, C. alutaceus n. sp.; 102, C. balli n. sp.; 103, C. girardianus n. sp.; 104, C. gigas n. sp.; 105, C. cateianus n. sp.; 106, C. deceptus n. sp. Abbreviations: sd, tubular extension. Scale bar = 0.5 mm.