Larinus rudicollis Petri, 1907

Gültekin, Levent, 2008, Taxonomic review of the stem-inhabiting trehala-constructing Larinus Dejean, 1821 (Coleoptera: Curculionidae): New species, systematics and ecology, Zootaxa 1714, pp. 1-18 : 9-11

Larinus rudicollis Petri, 1907 ( Figs. 2 , 7, 10, 13, 14 )

Redescription. Body length 8.4–13.5 mm. Black ( Fig. 2 ); antennal scape dark brown in basal 2/3. Head with short bifid white scales on ventral surface and along latero-ventral margin of eye, dorsal margin of eye with short semi-erect hair-like scales. Rostrum with short and moderately long, hair-like scales. Pronotal disc without white spots, clothed with very short whitish pubescence. White lateral areas on pronotum with semi-erect narrow lanceolate short pubescence, two lateral branches projecting dorsally. Weakly developed ocular lobes with short setae. Elytra with scattered sparse white spots constituted by subrecumbent short narrow lanceolate scales condensed at base of intervals 2 and 4, at margins of elytral disc, on intervals 8 and 9, and in apical part of interval 3. Underside densely clothed with short hair-like scales; anal ventrite with semi-erect scales. Scale tufts on apical margin of ventrites not reaching basal margin of next ventrite.

Male. Rostrum 2.38 times as long as wide, 0.71 times as long as pronotum, sub–cylindrical; lateral surface flat between eyes and antennal scrobe, with coarse merging punctures forming longitudinal wrinkles. Rostrum weakly narrowing from eyes to antennal insertion in dorsal view. Apical part of rostrum 0.91 times as wide as its basal part, 1.22 times as wide as fore femur. Ventral margin of antennal scrobes clearly visible from above. Surface of rostrum more or less shiny, with fine and slightly larger punctation. Fovea on dorsal surface wide, lanceolate, and reaching up to level of antennal insertion.

Antennae inserted at 0.45 length of rostrum from apex. Funicle shorter than rostrum, gradually widening apically. First segment 1.27 times as long as second, 1.75 times as long as wide; second segment 1.31 times as long as wide, other segments short, gradually becoming more transverse. Club elongate oval with acuminate apex.

Eyes flat, transverse, with dorsal part wider than ventral one. Frons with small, narrow, moderately deep fovea.

Pronotum 1.37 times as wide as long, widest in basal part, angularly narrowing toward apex, neck-like constricted in apical fifth. Anterior margin not produced over head. Base deeply bisinuate, scutellar area distinctly produced toward scutellum. Ocular lobes moderately developed; apical margin of prothorax evenly curving ventrally, deeply emarginate below ocular lobes. Disc moderately convex, with coarse, rather regular punctation, with punctures merging in some areas to form fine wrinkles. Interspaces between punctures shiny, with very fine secondary punctation.

Elytra 1.37 times as long as wide, 1.36 times as wide as pronotum at their widest place, subparallel-sided in basal third, moderately narrowing toward apex. Base of each elytron projecting forward, more strongly so on intervals 2 to 5, there reaching level of pronotal base. Intervals 2 and 3 at base slightly wider than other interspaces. Stria 1 deep, furrow-shaped on basal part of disc, stria 9 wider and deeper, other striae shallow, formed by elongate connected punctures. Intervals of elytra densely and finely wrinkled. Discal and apical prominences of elytra strongly convex.

Fore femur 1.09 times as long as rostrum, 1.15 times as wide as middle femur, moderately swollen; middle and hind femora weakly swollen medially. Tibiae moderately long, fore tibia moderately out curved, middle and hind tibiae straight. Fore and middle tibiae with large, wide unci (subequal in length); uncus on hind tibia slightly and smaller than that on middle tibia. Fore tibia weakly widening apically, with inner surface deeply emarginated, more deeply so in apical half. Inner margin with small blunt denticles except for basal sixth; two denticles closest to uncus larger and sharper, concealed by tuft of setae. Apical comb of fore tibia hanging over base of uncus; spines short, dense, partly connate basally. Spines in apical comb of middle and hind tibiae longer and denser than those on fore tibia. Middle tibia 0.80 times as long as fore tibia, with inner margin weakly emarginate medially and bearing very small blunt denticles concealed by dense setae. Tarsal segment 1 triangular, longer than wide; segment 2 moderately transverse, slightly widening apically. Fore tarsus wider than middle and hind tarsi. Onychium moderately widening apically, projecting from lobes of segment 3 by about 2/3 of its length. Claws connate, weakly diverging, with parallel outer margins.

Ventrite III with moderately deep wide median depression, ventrite IV weakly depressed only near basal margin; these two ventrites with punctures partly concealed by scales. Ventrite V with posterior margin narrowly semi-circular, with narrow depressed area at sides.

Aedeagus in dorsal view narrowing from base to apex, constricted before middle, then strongly swollen ( Fig. 7 ), mesophallus strongly narrowing toward sharp apex.

Female. Rostrum 2.91 times as long as wide at base, 0.89 times as long as pronotum; apical part of rostrum 1.15 times as wide as fore femur; in lateral view apical part of rostrum weakly curved. In dorsal view, rostrum weakly constricted in front of antennal insertion; two dorsal foveae deeper and longer, their traces continuing to apex as narrow and shallow sulci.

Antennae inserted at 0.43 length of rostrum from apex. Frontal foveae as deep as in male.

Pronotum 1.39 times as wide as long. Disc with coarse rugosely wrinkled punctures.

Elytra 1.34 times as wide as pronotum, 1.40 times as long as wide. White pattern at base of intervals 2 and 4 longer and more evident than in male. Second to fifth striae at base sulciform, with merged punctures. Punctures on elytron underside rounded, some punctures merged and each with two points in the centre.

Fore femur 1.23 times as wide as middle one. Unci on tibiae slightly longer and stronger than in male. Fore uncus moderately wide, subuncus concealed by tuft of long coarse setae. Denticles on inner margin of fore tibia slightly longer and sharper than in male.

Tergite VIII ( Fig. 10 ) moderately wide, 1.69 times as wide as long, triangular, sides strongly emarginate in basal quarter and weakly emarginate in apical half. Apical third more heavily sclerotized than the remainder. This area with dense, moderately long semi-erect hair-like setae, apical and lateral margins bearing dense longer semi-erect setae producing posteriorly. Sternite VIII ( Fig. 13 ) tulip-shaped, well sclerotized, apical margin bearing rather dense semi-erect short hair-like setae. Spermatheca with very sharp apex ( Fig. 14 ).

Figures

FIGURES 1 – 4. Dorsal habitas of trehala-building Larinus species. 1, Larinus capsulatus sp. n., male, holotype; 2, L. rudicollis, lectotype; 3, L. hedenborgi, lectotype; 4, L. nidificans, male.

FIGURES 5 – 14. 5 – 8. Dorsal aspect of aedeagus. 5, Larinus nidificans; 6, L. hedenborgi; 7, L. rudicollis; 8, L. capsulatus sp. n. 9 – 14. Female genitalia; 9, tergite VIII of L. capsulatus; 10, tergite VIII of L. rudicollis; 11, spermatheca of L. capsulatus; 12, sternite VIII of L. capsulatus; 13, sternite VIII of L. rudicollis; 14, spermatheca of L. rudicollis.