Laparocerus humeralis, 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 : 23-25

Laparocerus humeralis n. sp.

( Figs. 8 A, 13E-F)

Dimensions, holotype (ɗ). Length: total (without rostrum) 5.60 mm, head 1.25 mm, rostrum 0.66 mm, scape 1.50, mm, funicle 1.84 mm, segments (1st/ 2nd/ 3rd/ 4th) 0.38 /0.46 /0.22 / 0.22 mm, club 0.56 mm, eyes 0.32, pronotum 1.30 mm, elytra 4.20 mm, tibiae (fore /mid /hind) 1.70 /1.50 / 1.74 mm. Width: head (with eyes) 1.02 mm, head (between eyes) 0.59 mm, rostrum (with pterygia) 0.76 mm, rostrum (minimum dorsal /ventral) 0.50 mm / 0.66 mm, rostrum (base) 0.70 mm, scape (maximum) 0.16 mm, club 0.16 mm, pronotum (anterior /maximum /posterior) 1.10 /1.70 / 1.50 mm, elytra (maximum) 2.45 mm. Height: abdomen 2.10 mm.

Males. Length 5.3–5.6 mm, elongate-elliptical. Integument shiny, piceous, antennae and tarsi paler. Vestiture composed of small, long, linear, testaceous (with coppery or greenish tint), whitish and hyaline scales, arranged on elytra in mosaic-pattern and with few small, curved, protruding setae. Antenna slender, scape 1.15× longer than pronotum, slightly arcuate, clearly capitate in apical quarter; funicle 1.2× longer than scape; 2nd segment markedly longer than 1st, slightly longer than 3rd + 4th together; club oblong, narrow, as long as three previous segments combined. Head broad-conical, not depressed at frons, not inflated at vertex; rostrum subquadrangular, narrower dorsally than ventrally, genae clearly visible from above; prorostrum with small median longitudinal keel, laterally punctate; epistomal keel marked only laterally; metarostrum subcanaliculate, lateral border slightly convergent basad, incomplete. Frontal fovea small, deep. Eyes oval (major axis 0.54× inter-ocular distance), not reaching border of frons; moderately protruding (convexity 38%), asymmetrical (vertex shifted backwards). Dorsal integument densely and shallowly punctate, particularly at vertex. Pronotum large, convex, 0.66 × width of elytra, moderately transverse (L/W ratio 0.76 ×), sides evenly curved, maximum width at middle; anterior margin narrower than posterior, basal margin thinly rimmed. Surface shiny, with separate deep macropunctures (smaller than on striae) and many micropunctures in interspaces; median line faint. Scutellum triangular, right-angled, squamose. Elytra elongate-elliptical (L/W ratio 1.7 ×), uniformly curved; maximum width behind middle; fairly convex, 3.2 × longer than pronotum, not much broader at base. Basal line slightly concave; shoulders very short but angular, marked by humeral carina. Punctures of striae foveate, not much larger than distance between them; intervals shiny, smooth or slightly rough, 7th interval shortly and markedly inflated at base. Vestiture of linear scales arranged in mosaic pattern of whitish, testaceous and dark. Short, dark, curved setae along intervals, barely protruding from vestiture of scales except at apical third (conspicuous in profile). Legs slender, tibiae apically hairy, also tarsi; protibia moderately incurved apically; apex with outer angle broadly rounded, inner one sharp, with strong mucro; meso- and metatibia incrassate internally at apex, with strong and smaller mucro, respectively. Ven t er. Integument shiny, covered by fairly open pubescence of long, hair-like scales; intermesocoxal ridge poorly developed, sloping down; mesosternum and basal ventrites with transverse median corrugation; last ventrite apically truncate. Abdominal convexity 85%. Aedeagus (fig. 13E–F) fairly long (0.75× length of elytra), smoothly arcuate, evenly convergent at apex; apex simple, not very sharp, slightly curved upwards. Internal sac posteriorly shorter than temones; bearing one set of parallel rows of short thick denticles; denticular field of muscular sheath weakly developed.

Female. As male (length 5.6 mm) but broader, almost rectangular. Elytra much broader (1.6× broader than pronotum instead of 1.5×), nearly parallel-sided, quadrangular at base, ogival at apex, with small point directed downwards; shoulders much more prominent, humeral carina well developed. Dorsum along intervals with conspicuous rows of protruding long, black, recurved setae (0.5× length of onychium). Protibia straight, unarmed. Metasternum and basal ventrites not transversely rugose; last ventrite apically rounded.

Etymology. The specific epithet is a Latin adjective referring to the reduced but sharply marked shoulders of this species.

Remarks. Laparocerus humeralis is similar in appearance and related to L. obscurus Wollaston, 1864 from Tenerife. It is more elliptical, with smaller and more protruding eyes, the frons not depressed, the male protibia less curved and emarginate, the 2nd funicle segment not much longer than 3rd+4th; the shoulders marked but not advanced, the elytral integument shiny and not alutaceous, and the black setae much shorter in males (hardly protruding) but longer in females. The aedeagus is very similar but proportionally much longer.

L. humeralis shares many features with L. roudieri , but its size exceeds 5 mm and the females bear long, protruding black setae all over the elytra (absent in L. roudieri ), while in the males the hardly protruding elytral setae, elliptical elytra, reduced, sharp-angled shoulders with a humeral carina, head not depressed at frons, asymmetrical eyes with no trace of a postocular granule and the more incurved protibia are suitable diagnostic characters.

Material examined. Holotype: La Gomera: Hermigua: San Juan, 620 m (UTM = 28R 0 2837 31173), 11- 2-2006, leg. A. Machado, 1 ɗ (right antenna damaged) ( TFMC, reg. CO-15516). Paratypes: same data, 1 ɗ, 1Ψ; same data, 9-12-1996, 6 exx.; same data, 19-2-2007, 7 exx. ( AMC); same locality, 9-12-1966, leg. P. Oromí, 3 exx. (POM); same locality, 9-12-2006, leg. R. García, 2 exx. (RGB).

Distribution and ecology. This species is restricted to the island of La Gomera. It has been collected only in the northern humid valley of Hermigua, on the slopes in remnants of the original thermophilous vegetation. The few specimens collected were beaten at night from Rubus, Aeonium and Artemisia thuscula .

Figures

FIGURE 8. New Laparocerus species from La Gomera, holotypes: (A) L. humeralis, (B) L. mulagua. Scale = 2 mm