Cercopeus paulus O’Brien, Ciegler and Girón, 2010

O’Brien, Charles W., Ciegler, Janet C. & Girón, Jennifer C., 2010, Weevils of the genus Cercopeus Schoenherr from South Carolina, USA (Coleoptera: Curculionidae: Entiminae), Insecta Mundi 2010 (141), pp. 1-29 : 14-16

Cercopeus paulus O’Brien, Ciegler and Girón , new species

( Fig. 9, 10 , 31, 37, 45)

Diagnosis. Body short-oval to elongate-oval; integument shining, black to dark reddish brown; clothed with black, brown, and few whitish tan to white, oval to round, subcontiguous to imbricate, recumbent scales; basal 1/3 of elytral disc brown surrounded with maculae and fasciae of imbricate pale and black scales; and with moderately dense, coarse, bristle-like, erect setae.

Description. Holotype female. Length, pronotum and elytron: 2.6 mm. Width, elytra: 1.35 mm. Rostrum nearly straight, weakly raised at antennal insertion in lateral view, apical 1/3 weakly depressed; dorsomedian area not impressed; basal 2/3 densely clothed with coarse recumbent large scales concealing punctures; apical 1/3 subglabrous with moderately coarse, subcribrate punctures and moderately sparse, elongate, golden brown, suberect setae; with nasal plate moderately well-defined, not carinate or punctate. Head with frons with large, deep, median fovea; densely clothed with scales at base of rostrum concealing punctures; punctures behind frons substriate, elongate-oval, each filled with recumbent scale or strap-like seta; eyes round-oval, moderately strongly convex. Antennae moderately stout; scape short, in repose not reaching pronotum, moderately clavate, with dense elongate recumbent scales and moderately dense long coarse suberect setae; funicular antennomere 1 about 0.50× longer than 2 and 0.50× wider, 3-5 slender, subequal in length, 6 and 7 broad and rounded, subequal in length, 1/2 as long as 2; club short, broad-oval, slightly longer than funicular antennomeres 1 + 2 (Fig. 31). Prothorax not transverse, 0.98× as wide as long, sides strongly expanded from distinct subapical constriction to widest at middle, there with sides rounded and narrowed to truncate base, base with narrow collar; disc on median 2/3 with large contiguous to separate punctures, with brown recumbent scales nearly concealing integument, laterally with denser round recumbent white scales concealing integument; lateral margins of disc broadly rounded in lateral or anterior view; sides rugosely, granularly coarsely punctate with sparse, grayish to brown, round to oval, recumbent scales nearly concealing integument; disc with moderately dense, long, coarse, suberect setae. Elytra short broad-oval, broadest at middle behind rounded humeri, then sides roundly evenly narrowed to rounded apex; 0.77× as wide as long; median area of disc maculate with white, gray brown, and dark brown scales, bordered by pale tan to whitish uneven narrow fascia of scales, latter bordered unevenly with brown fascia; declivity, lateral areas, and inflexed lateral area densely clothed with recumbent, dense, white to tan scales; strial punctures deep, elongate and nearly concealed by dense scales, separated by own diameter; intervals uneven in width, flat, each with even row of coarse bristle-like, erect setae, and dense, round to oval, contiguous to imbricate recumbent scales. Legs moderately stout; femora moderately clavate; with dense, not contiguous, recumbent scales and suberect fine setae; foretibia externally apically roundly expanded, with nine noncontiguous spines and short acute mucro; nearly straight with slight sinuate inner curvature; inner margin not denticulate; hind tibia with two acute moderately stout anterior apical black spines, and outer margin with 12 short to moderately long coarse sharp pale spines becoming longer posteriorly. Venter with dense non- contiguous recumbent plumose scales on pro-, meso-, and metasternum; abdominal sterna with moderately sparse recumbent setae, sterna I and II laterally with few elongate-oval shining recumbent scales; entire venter with sparse, fine, punctures; abdominal sternum I broadly weakly convex, 1.06× as long as II; II transversely flattened, and 1.42× as long as subequal weakly convex III + IV together; V about 0.82× as long as II and basal 2/3 nearly flat with apical 1/3 depressed; sterna I, II, and V coarsely punctate, with apical 1/3 of V less densely punctate; III + IV with line of basal punctures. Genitalia: Tergum VII ( Fig. 45a ) 1.3× wider than long, with anterior margin rounded, 1.6× wider than posterior margin, lateral margins nearly straight, posterior margin emarginate, surface with short setae in posterior third; in lateral view, dorsal outline straight. Tergum VIII ( Fig. 45b ) with anterior margin slightly emarginate; lateral margins nearly straight, convergent on apical third; anterior margin 2.3× wider than posterior margin; posterior margin emarginate, with setae on marginal area. Sternum VIII ( Fig. 45c ) 0.7× length of sterna I-V together, with lamina semihexagonal, 2.3× longer than wide, rounded at apex, with apicolateral area and median basilongitudinal region more sclerotized than basilateral regions, with 2-3 lateral submarginal setae. Coxites + styli ( Fig. 45d ) 0.7× length of lamina of sternum VIII; apex of coxites with two robust setae and few shorter setae; styli dorsoapically inserted, 2.7× longer than basal width, dorsally narrowed apicad of midpoint to apex, with two robust setae. Genital chamber 0.7× length of sternum VIII. Spermatheca ( Fig. 45e ) 1.2× longer than wide, j-shaped; cornu straight, with an apical projection directed to collum; ramus abruptly projected, apically truncate, laterally rounded; collum apically truncate, laterally widely rounded; surface reticulate.

Allotype male. Same as female holotype except: Length, pronotum and elytron: 2.55 mm. Width, elytra: 1.25 mm. Prothorax about as wide as long, basal margin without collar. Elytra elongate-oval, broadest behind rounded humeri at basal 1/5, then sides subparallel to just anterior to declivity, and evenly narrowed to rounded apex; 0.85× as wide as long. Legs with foretibia not expanded externally, with weak denticles on inner margin, and with long strongly curved acute mucro; hind tibiae with one stout anterior apical spine and outer margin with three short blunt pale spines, and cluster of seven posterior long, moderately coarse, sharp pale spines. Venter with abdominal sterna I and II broadly weakly convex; abdominal sterna I-IV with basal row or narrow band of recumbent scales. Genitalia: Tergum VIII ( Fig. 37a ) slightly wider than long, with anterior margin nearly straight, 1.6× wider than posterior margin, lateral margins convergent on apical half, posterior margin slightly rounded, with setae in posterior third; in lateral view ( Fig. 37b ), dorsal outline sinuate. Sternum VIII forming an entire plate, very lightly sclerotized, slightly narrower than posterior margin of tergum VIII, with apodeme (spiculum relictum) nearly 2× longer than wide, distally darkened. Sternum IX (spiculum gastrale, Fig. 37c ) with basal plate bifurcate, forming two opposed triangles, each nearly 3× longer than wide; apodeme nearly 0.2× width of aedeagus in lateral view, as long as 1.4× length of aedeagus. Tegmen ( Fig. 37d ) with tegminal apodeme 0.7× length of aedeagus; basal piece connate with tegminal plate; tegminal plate mesally, roundly, posteriorly projected. Aedeagus in dorsal view ( Fig. 37e ) 3.5× longer than mesal width, lateral margins subparallel, slightly emarginate at mesal region; apex ( Fig. 37f ) widely rounded; in lateral view ( Fig. 37g ) dorsally strongly convex, 5× longer than greatest width. Endophallus with two convergent anteapical sclerites closing the ostium and several rows of small teeth. Aedeagal apodemes 1.4× longer than aedeagus.

Intraspecific variation. The length (pronotum plus elytra) ranges from 2.45 to 3.50 mm, the width from 1.15 to 1.80 mm. Some specimens have a large distinct basal dark brown area surrounded by a typical black and pale fascia; the inflexed areas next to the hind femur in some specimens have sparse widely separated recumbent scales.

Remarks and comparative notes. This species is similar to several small species in the North and West, but is by far the smallest in the Southeast. Its size alone will distinguish it from other southeastern species. Females of this species are similar to small individuals of C. chrysorrhoeus , but lack the subapical spine on the foretibia; they resemble C. alexi and C. skelleyi , but lack the basal process of the pronotum.

Range. Known only from the type locality in central South Carolina.

Materials examined. On hand for this study were 15 specimens, 8 males and 7 females.

Holotype female, allotype male (both in CASC on long-term loan to CWOB), and 1 paratype: “S[OUTH] C[AROLINA] Richland Co., Ballentine , N34 o 08.119', W81 o 13.663', 25-X-2006 / J. C. Ciegler, berlese, sifted, mixed woods”.

Paratypes. S[OUTH] C[AROLINA] Richland Co., Ballentine , 5-XI-2006, N34 o 08.116', W81 o 13.685' / J. C. Ciegler, berlese, sifted, mixed woods (4) ; same except N34 o 08.115', W81 o 13.635' (4); same except 6-I-2007, N34 o 08.114', W81 o 13.659', (2); same except 12-II-08, N34 o 08.127', W81 o 13.674' / nr. rotted stump (1); same except N34 o 08.130', W81 o 13.676', 2-II-08 (1). Paratypes are in the following collections: CASC, CUAC, CWOB, JCCC, SCSM, and USNM.

Etymology. This specific epithet is from the Latin noun, paulus (=little, small) and refers to the size of this small species.

Figures

Figure 6-10. Habitus of Cercopeus species: dorsal view, lateral view, and life-size silhouette. 6) C. femoratus, male. 7) Same, female. 8) C. maspavancus, female. 9) C. paulus, male. 10) Same, female.

Figure 40-48. Female genitalia of Cercopeus species: a. tergum VII, dorsal view; b. tergum VIII, dorsal view; c. sternum VIII, ventral view; d. coxite, lateral view; e. spermatheca. 40) C. alexi. 41) C. chrysorrhoeus. 42) C. cornelli. 43) C. femoratus. 44) C. maspavancus. 45) C. paulus. 46) C. skelleyi. 47) C. strigicollis. 48) C. tibialis. Scale bars: 0.5 mm for a, b and c; 0.2 mm for d and e.

Figure 34-39. Male genitalia of Cercopeus species: a. tergum VIII, dorsal view; b. tergum VIII, lateral view; c. sternum IX (spiculum gastrale); d. tegmen; e. aedeagus, dorsal view; f. apex of aedeagus, dorsal view; g. aedeagus, lateral view. 34) C. alexi. 35) C. cornelli. 36) C. femoratus. 37) C. paulus. 38) C. skelleyi. 39) C. tibialis. Scale bar = 0.5 mm.