Cercopeus skelleyi 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 : 16-18

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

( Fig. 11, 12 , 32, 38, 46)

Diagnosis. Body elongate-oval to broad-oval; integument shining, dark reddish brown to black; clothed with black, brown, and few whitish tan to white, oval to elongate-oval, recumbent scales; some with scales predominantly grayish white with large basal black and brown elytral macula; and with moderately dense, distinct, suberect, moderately coarse setae.

Description. Holotype female. Length, pronotum and elytron: 4.00 mm. Width, elytra: 2.25 mm. Rostrum weakly curved, dorsal line scarcely curved in lateral view, apical 1/3 weakly depressed; dorsomedian area narrowly impressed from base to apical 1/3; basal 2/3 densely clothed with scales concealing large punctures; small shining granules evident among scales; apical 1/3 subglabrous with moderately coarse, substriate punctures and moderately sparse, elongate golden brown and white, suberect setae; with nasal plate sharply defined, not carinate or punctate. Head with frons strongly transversely impressed, with shallow median fovea; densely clothed with large elongate white scales, nearly concealing substriate punctures; punctures behind frons substriate, smaller, with smaller sparse scales; eyes roundoval, moderately strongly convex. Antennae moderately stout; scape moderately clavate, with moderately dense elongate recumbent scales and moderately dense long coarse suberect setae; funicular antennomere 1 about 0.17× longer than 2 and 0.50× wider, 3-7 subequal in length, 1/2 as long as 2, each gradually wider toward club; club short, broad-oval, 2× as long as and 2× as wide as funicular antennomere 1 (Fig. 32). Prothorax as wide as long, sides moderately evenly rounded from moderate subapical constriction to widest at middle, there roundly narrowed to truncate base; disc on median 3/4 with large and small contiguous deep substriolate punctures, with brown recumbent scales not concealing punctures, laterally with denser round recumbent white scales nearly concealing all punctures, except few setabearing punctures; disc becoming strongly curved laterally; base with median short triangular process; lateral margins of disc rounded in anterior view; sides rugosely, granularly coarsely punctate with sparse, grayish, round to oval, recumbent scales; disc with moderately dense, long, coarse, suberect setae. Elytra short broad-oval, 0.77× as wide as long, broadest at middle behind rounded humeri, sides then roundly evenly narrowed to rounded apex; median area of disc dark brown to black, bordered by pale tan to whitish uneven narrow fascia of scales, latter bordered with wider black band, declivity and lateral areas densely clothed with recumbent imbricate white to tan scales; inflexed lateral area with scarcely sparser, separate, smaller, round, recumbent scales; strial punctures deep, elongate and distinct, separated by own diameter; intervals uneven in width, flat, each with one uneven row of moderately fine, suberect setae, and dense, round to oval, imbricate recumbent scales. Legs stout; femora strongly clavate; with dense, recumbent scales and suberect, fine setae; foretibia apically externally and internally roundly expanded, with nine spines and stout short acute mucro; nearly straight with moderate sinuate inner curvature; inner margin not denticulate; hind tibia with two blunt stout anterior apical spines, and outer margin with 15 moderately long coarse sharp pale spines becoming longer posteriorly. Venter with dense to sparse noncontiguous recumbent plumose scales on pro-, meso-, and metasternum, and sternum I, especially laterally, and on articulating surface of forecoxa; sparse, narrow, strap-like, recumbent scales scattered unevenly on pro-, meso-, and metasternum and basal area of sternum I; abdominal sterna all with moderately dense, fine, decumbent setae; entire venter with sparse, fine, punctures; abdominal sternum I transversely impressed between hind coxae, 1.33× as long as II; II weakly convex, and 1.50× as long as subequal III + IV; V about 0.83× as long as II and weakly longitudinally concave laterally in apical third. Genitalia: Tergum VII ( Fig. 46a ) slightly wider than long, with anterior margin rounded, 1.7× wider than posterior margin, lateral margins nearly straight, posterior margin straight, surface with setae on apical half; in lateral view, dorsal outline straight. Tergum VIII ( Fig. 46b ) with anterior margin slightly emarginate; lateral margins nearly straight, convergent on apical third; anterior margin 2.5× wider than posterior margin; posterior margin rounded, with setae on marginal area. Sternum VIII ( Fig. 46c ) 0.7× length of sterna I-V together, spear-shaped, with lamina 2.2× longer than wide, rounded at apex, with apicolateral area and median basilongitudinal region more sclerotized than basilateral region, with three lateral submarginal setae. Coxites + styli ( Fig. 46d ) 0.9× length of lamina of sternum VIII; apex of coxites with two short anteapical and two slightly longer apical setae; styli apically inserted, 2.5× longer than basal width, apically rounded, with three long, one short apical, and one short anteapical setae. Genital chamber 0.7× length of sternum VIII. Spermatheca ( Fig. 46e ) 1.2× longer than wide, jshaped; cornu straight; ramus abruptly projected, apically truncate, laterally rounded; collum apically rounded; surface reticulate

Allotype male. Same as female holotype except: Length, pronotum and elytron: 4.00mm. Width, elytra: 2.10 mm. Prothorax with disc on median 2/3 with large and small contiguous deep punctures, becoming substriolate at median 1/3, with brown recumbent scales not concealing punctures, laterally with denser round recumbent white scales nearly concealing all punctures. 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. Legs with foretibia more slender and more sinuate, strongly curved at apical 1/3, not produced externally, inner margin of apical half granulate-denticulate; 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 sternum I broadly very deeply impressed, impression continuing shallowly on flattened sternum II; sternum V basally weakly convex, with narrow shallow transverse subapical impression. Genitalia: Tergum VIII ( Fig. 38a ) slightly wider than long, with anterior margin rounded, 2× wider than posterior margin, lateral margins convergent on apical half, posterior margin slightly rounded, surface lightly sclerotized on basal and basimesal regions, with setae in posterior third; in lateral view ( Fig. 38b ), dorsal outline sinuate. Sternum VIII forming an entire plate, very lightly sclerotized, 0.6× width of posterior margin of tergum VIII, with apodeme (spiculum relictum) triangular, distally 1.4× wider than long, darkened. Sternum IX (spiculum gastrale, Fig. 38c ) with basal plate bifurcate, forming two opposed rhombi, nearly 1.5× longer than wide each; apodeme nearly as wide as aedeagus in lateral view, 1.4× length of aedeagus. Tegmen ( Fig. 38d ) with tegminal apodeme slightly shorter than aedeagus; basal piece connate with tegminal plate; tegminal plate mesally slightly, triangularly, posteriorly projected. Aedeagus in dorsal view ( Fig. 38e ) 3.8× longer than mesal width, lateral margins subparallel, slightly emarginate at mesal region; apex ( Fig. 38f ) truncate; in lateral view ( Fig. 38g ) dorsally strongly convex, 6.4× longer than mesal width. Endophallus with pair of subapical sclerotized plates closing the ostium and basal, long n-shaped sclerite. Aedeagal apodemes 1.6× longer than aedeagus.

Intraspecific variation. The length (pronotum and elytra) ranges from 3.1 to 4.2 mm, the width from 1.5 to 2.1 mm. Specimens vary in the sculpture of the pronotum from markedly striolate on median 2/3 to exclusively punctate without striolae; they may or may not have a glabrous midline. Color pattern of elytra varies from that described to completely mottled with gray and white scales without distinct pattern; the fascia described may be uneven and maculate in some specimens.

Remarks and comparative notes. This species is rather distinctive, although because of the strongly striolate pronotum, females of this species are similar to those of the larger C. strigicollis , but the latter species has an anteapical tooth on the foretibia, has round contiguous convex shiny scales, and lacks a median process on the base of the pronotum. Males somewhat resemble large specimens of C. paulus with their punctate pronotum, but their foretibia is slightly bent near the apex and the midfemur is tuberculate. Males of C. femoratus , which also have tuberculate middle femora, differ in having a markedly striate pronotum. Females closely resemble those of C. alexi , which has a strongly strioalate pronotum and C. paulus which lacks any basal process of the pronotum, but some individuals of C. skelleyi are similar.

Range. Known only from Aiken and Hampton counties in western South Carolina.

Materials examined. On hand for this study were 73 specimens, 32 males and 41 females.

Holotype female, allotype male (both in CASC on long-term loan to CWOB), and 16 paratypes: “S[outh]C[arolina], [Aiken Co.] 8.3 mi N Aiken, Hwy. 1,5- III-2001 C.W. O’Brien / berlese scrub oak litter”.

Paratypes. S[OUTH]C[AROLINA], Aiken Co., 1.3 mi, N jct.I-20 & US-1, 4-14-I-1987, P. Skelley (4) ; same except 5.3mi E, Montmorenci Post, Office on US-78, 7-10-III-1992, P. Skelley, pitfall (1) ; SOUTH CAROLINA: Aiken Co., 1.3 mi. N jct. I-20& US 1. 4-14-I-1989 P. Skelley pigdung & malt pitfall in sandhill scrub (4) ; S[outh]C[arolina], 5.7 mi SE Mont-, morenci P. Office , 5-III-2001,sifting oak-pine C.W. O’Brien (4) ; same except 8 mi N. Aiken, Hwy 1, 20-I-2002, O’Brien & Turnbow / Under wood on ground (6) ; same except 4.9 mi, SW Montmorenci P.O., Hwy 78 20-I-2002 O’Brien & Turnbow / sifted & heated oak-pine litter (7) ; same except Montmorenci , 22-I-2008, N33 o 30.446', W81 o 33.042' / J.C. Ciegler, berlese sifted, oak. lichens (1) ; same except N33 o 30.325', W81 o 32.670' / piled up litter (3); same except N33 o 30.322', W81 o 32.688' / under blackjack oak (4); same except US-1, 1.2 mi. n. of I-20, N33 o 40.925', W81 o 40.105' / oak, lichens (1); SC: Aiken Co., Aiken State Park , 11-II-2007, N33 o 33.120’, W81 o 29.846’ / J. C. Ciegler, berlese sifted, under logs (2) ; same except 15-V-2007 (3); same except N33 o 33.119', W81 o 29.840' 20-II-08 / hollow below log (12); same except N33 o 33.131', W81 o 29.856' / by oak stump (5); same except N33 o 33.140', 81 o 29.852'/ woods by old log (1); SC: Hampton Co., Solomons Crossing ca. 15 mi. S. Hwy. 301, at Co. line, 9-I-2005 C.W. O’Brien & R.H. Turnbow / berlese sifted hardwood litter on roadside (2) ; same except Solomons Crossroads , 18-I-2008, N32 o 47.646', W81 o 19.285' / J.C.Ciegler, berlese sifted, decid. roadside (2) . Paratypes are in the following collections: BMNH, CASC, CMNC, CUAC, CWOB, FSCA, JCCC, JFCC, SCSM, and USNM.

Etymology. This species is named in honor of our friend and colleague, Dr. Paul E. Skelley, who collected the first known series of this and many other species, and made them available to us for study.

Figures

Figure 11-15. Habitus of Cercopeus species: dorsal view, lateral view, and life-size silhouette. 11) C. skelleyi, male. 12) Same, female. 13) C. strigicollis, female. 14) C. tibialis, male. 15) 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.