Laparocerus spinimanus, Machado, Antonio, 2007

Machado, Antonio, 2007, New species of Laparocerus Schönherr, 1834 from La Gomera, Canary Islands (Coleoptera, Curculionidae, Entiminae), Zootaxa 1643, pp. 1-38 : 9-10

Laparocerus spinimanus n. sp.

(Figss 3B, 10F–G, 16B, 18F)

Dimensions, holotype (ɗ). Length: total (without rostrum) 6.60 mm, head 1.46 mm, rostrum 0.94 mm, scape 1.56, mm, funicle 1.96 mm, segments (1st/ 2nd/ 3rd/ 4th) 0.24 /0.44 /0.30 / 0.26 mm, club 0.60 mm, eyes 0.40, pronotum 1.65 mm, elytra 4.70 mm, tibiae (fore /mid /hind) 1.80 /1.64 / 1.90 mm. Width: head (with eyes) 1.16 mm, head (between eyes) 0.62 mm, rostrum (with pterygia) 0.81 mm, rostrum (minimum dorsal /ventral) 0.54 mm / 0.66 mm, rostrum (base) 0.60 mm, scape (maximum) 0.18 mm, club 0.20 mm, pronotum (anterior /maximum /posterior) 1.25 /1.95 / 1.75 mm, and elytra (maximum) 3.05 mm. Height: abdomen 2.35 mm.

Male. Length 6.3 – 7.0 mm, elongate-elliptical. Integument piceous or blackish, densely covered with linear, decumbent scales of whitish colour with coppery or bluish tint, forming mosaic pattern on elytra, frequently converging in groups of three at apex; a few curved, short, brown, protruding setae at apex; legs usually ferrugineous. Antenna slender; scape clavate, shorter than pronotum, much shorter than funicle (0.80×), slightly curved in basal half; funicle long, second segment more than 1.5× longer than first, 3–5th capitate; club fusiform, not broader than scape, as long as three previous segments together. Head subconical; rostrum long (L/ W 1.7 ×), dorsally parallel-sided, flat or slightly concave; prorostrum laterally keeled and punctate; epistomal carina obsolete in middle; pterygia robust, prominent; frons with short deep median fovea. Eyes prominent, almost hemispherical (convexity 47%), slightly asymmetrical (more convex posteriorly); close to but not reaching lateral border of frons. Integument moderately punctate, beset with scales except for completely smooth median channel of prorostrum. Pronotum convex, hardly transverse (L/W ratio 0.85), not rimmed; more constricted at front than at base; maximum width at middle. Integument densely and sharply punctate, irregularly interspersed with few larger punctures (double in size) that become denser at base and flanks. Vestiture of scales in median sector of pronotum hyaline or commonly abraded so that dark integument conspicuously visible; without median line. Scutellum small, equilateral, punctate. Elytra convex, elliptical, truncate at base (L/W ratio 1.54), 2.85 × longer than pronotum and scarcely wider (1.16 ×), evenly curved laterally, widest at middle. Shoulders absent. Striae marked by small shallow punctures; intervals completely flat. Integument subnitid, alutaceous, with fine micropunctures; linear scales arranged in mosaic pattern; protruding setae curved, small (2× length of scales), sparse, only in apical fourth. Legs normal; tibiae not carinate externally, hairy in apical half. Protibia sharply and strongly emarginate, with small protruding spine or prominent pointed angle at proximal end of emargination (middle of protibiae), apex blunt, not expanded laterally, with small mucro and short flattened setal mat on internal face; meso- and metatibia with smaller mucro. Ven te r. Thorax and coxae more densely squamose than ventrites; all coxae with moderately developed tufts; intermesocoxal keel long and low; last ventrite apically shortly truncate. Abdominal convexity 77%. Aedeagus (fig. 10F–G) with median lobe slender and arcuate (0.55× length of elytra); apical plate triangular, flat; apodemes very broad apically; internal sac with a very long field of strong denticles, a second shorter one parallel and a third much smaller proximal one; muscular sheath covered in fine denticles.

Female. As male (length 5.7–7.5 mm), elytra slightly broader (1.43× instead of 1.56×), apical declivity slightly steeper; protruding setae extended onto apical third, almost twice as long as in male, very conspicuous. Last ventrite apically shortly truncated. Pro- and mesotibia with tiny, inconspicuous mucro; protibia straight, not emarginate, without spine. Sternite VIII as in fig. 16B, spermatheca as in fig. 18F.

Etymology. The specific epithet spinimanus refers to the small inner spine of the male protibia, which is characteristic of this species.

Remarks. The smooth elliptical shape, clavate scape and the sharply emarginate male protibia with a median spine readily serve to distinguish L. spinimanus from all other species. Related species are L. gracilis and L. depressus , both also from La Gomera. The former is smaller and narrower to subcylindrical, with a shorter rostrum but larger and less protruding eyes and the emargination of the male protibia much smoother and devoid of any spine or sharp angle. The latter is as large but not elliptical, and its pronotum is constricted into a collar at the base, the elytra are characteristically depressed on the disc, with distinctly subconvex intervals, and the emargination of the male protibia is even less developed and only present in the apical third.

Material examined. Holotype: La Gomera: El Tabaibal (Hermigua), 260 m (UTM = 28R 0 28512 311900), 11-2-2006, leg. A. Machado, 1 ɗ ( TFMC reg. CO-15531). Paratypes: same data and collector, 18 exx. ( AMC, NHM); same data, leg. A. Aguiar, 3 ɗɗ, 13 ΨΨ ( AAC, TFMC, MNCN); same locality, 8-12- 2006, leg. A. Machado, 32 exx. ( AMC), leg. P. Oromí, 13 exx. (POM), 8-12-2006, leg. R. García, 11 exx. (RGB).

Distribution and ecology. Laparocerus spinimanus is endemic to La Gomera. It was collected at night on the windward part of the island at moderate altitudes, on a slope covered by a mixed vegetation of mainly Euphorbia regis-jubae , Convolvulus floridus and Ceballosia fruticosa . However, it was beaten from Bituminaria bituminosa shrubs growing intermixed in lower herbaceous vegetation, while another species, L. subopacus Wollaston, 1865 , fed on the Convolvulus and Ceballosia . L. spinimanus is apparently a winter species.