Cercopeus tibialis 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 : 19-21

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

( Fig. 14, 15 , 18, 23 , 33, 39, 48)

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

Description. Holotype female. Length, pronotum and elytron: 3.9mm. Width, elytra: 2.2 mm. Rostrum weakly curved, dorsal line nearly flat in basal 2/ 3 in lateral view; median area medially distinctly impressed from base to apical 1/3, basal 2/3 moderately sparsely clothed with scales, not concealing large shining punctures, apical 1/3 subglabrous with coarse substriate rugose punctures and moderately dense elongate white suberect setae; with nasal plate sharply defined, not carinate or punctate. Head with frons with large, median, round, shallow fovea, sparsely clothed with small white scales, not concealing large rugosely striate punctures; punctures behind frons striate, smaller, with smaller sparse scales; eyes elongate-oval, moderately strongly convex. Antennae moderately stout; scape moderately clavate, with sparse 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; club short, broad- oval (Fig. 33). Prothorax not transverse, 0.99× as wide as long, sides strongly expanded from narrowly carinate collared base to widest at basal third, there narrowed to short gradually subtubulate apex; disc completely striate, with small punctures at bottom of deep striae, subglabrous medially, lateral margins in part with denser round recumbent grayish scales partially concealing striae; striae straight medially from apex to pointed basal carinate process, and becoming strongly curved laterally; lateral margins of disc forming rounded distinct margin; inflexed area of pleuron concave, coarsely striate, moderately rugose above coxa; sides rugosely, coarsely punctate with sparse, grayish, round to oval, recumbent scales; disc with moderately dense, long, coarse, suberect setae; scales not forming distinct pattern. Elytra broad-oval, broadest just behind rounded humeri, then sides narrowed gradually in almost straight line to declivity and evenly narrowed to rounded apex; median area of disc dark brown to black, with pale tan to whitish uneven narrow fascia of scales inside and including humeri and along side margins and declivity, followed by black fascia and another pale fascia; inflexed lateral area with sparser, separate, smaller, round, recumbent scales; glabrous surface shining; strial punctures deep, round and distinct, separated by less than own diameter; intervals uneven in width, flat, each with one or two uneven rows of moderately fine, suberect setae, and dense, round to oval, recumbent scales. Legs moderately stout; femora very strongly clavate; with sparse, recumbent scales and suberect fine setae; foretibia nearly straight with moderate internal sinuation, inner margin not denticulate externally, apically roundly expanded with six spines and with ventrally directed process on inner apical margin at insertion of tarsomere 1 ( Fig. 23 ), flattened internally with two spines and short stout acute mucro; hind tibia with two blunt stout anterior apical spines, outer margin with almost 20 long moderately coarse sharp pale spines becoming much 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; venter with dense to cribrate, coarse to fine punctures except abdominal sterna with variable sparser, finer punctures; abdominal sternum I transversely impressed between hind coxa, 1.33× as long as II; II convex, and 1.50× as long as subequal weakly convex III + IV; V about 0.83× as long as II and weakly transversely concave in apical third. Genitalia: Tergum VII ( Fig. 48a ) 1.3× wider than long, with anterior margin rounded, 1.9× wider than posterior margin, lateral margins nearly straight, posterior margin slightly emarginate, surface with setae along apical area; in lateral view, dorsal outline straight. Tergum VIII ( Fig. 48b ) with anterior margin slightly emarginate; lateral margins nearly straight, rounded on apical fourth; anterior margin 2× wider than posterior margin; posterior margin slightly emarginate, with setae on marginal area. Sternum VIII ( Fig. 48c ) 0.6× length of sterna I-V together, spear-shaped, with lamina 1.9× longer than wide, rounded at apex, with apicolateral area and median basilongitudinal region more sclerotized than basilateral regions, with three lateral submarginal setae. Coxites + styli ( Fig. 48d ) 0.8× length of lamina of sternum VIII; coxites with four mid-sized and two slightly longer anteapical setae; styli dorsoapically inserted, 2× longer than basal width, apically mesally narrowed, with 5-6 apical setae. Genital chamber 0.7× length of sternum VIII. Spermatheca ( Fig. 48e ) 1.4× longer than wide, j-shaped; cornu curved; ramus abruptly projected, mesally swollen, apically truncate; collum apically rounded; surface of corpus, collum, and ramus reticulate.

Allotype male. Same as female holotype except: Length, pronotum and elytron: 4.00mm. Width, elytra: 2.1 mm. Legs even stouter, with forefemur asymmetrically swollen, external swelling with subapical blunt tooth-like process, inner surface in basal 2/3 with dense very long fine setae; midfemur basally lateroventrally granulate and strongly punctate, with strong inner tooth and angular ventral deep transverse groove followed by second strong inner tooth, outer margin swollen subacutely at apical third; foretibia strongly curved in apical 1/2, markedly internally expanded from base to midpoint, with deep curved concavity from midpoint to apex, with large tooth on outer margin of concavity, apically externally subacutely weakly expanded, with six short blunt spines and very short acute mucro; midtibia strongly sinuately expanded in basal 1/3, with strong long teeth, one each on inner and outer margins, apically deeply grooved from teeth to apex; hind tibia with one stout anterior apical spine and outer margin with 12 short blunt pale spines, and cluster of seven posterior long moderately coarse sharp pale spines. Venter with abdominal sternum I broadly deeply impressed, impression continuing shallowly on flattened sternum II; sternum V basally weakly convex, with narrow shallow transverse subapical impression; all abdominal sterna with very long, dense, fine, decumbent setae. Genitalia: Tergum VIII ( Fig. 39a ) slightly wider than long, with anterior margin rounded, 1.6× wider than posterior margin, lateral margins convergent in apical half, posterior margin nearly straight, surface lightly sclerotized on basal and basimesal regions, with setae in posterior half; in lateral view ( Fig. 39b ), dorsal outline sinuate. Sternum VIII forming an entire plate, very lightly sclerotized, 0.7× width of posterior margin of tergum VIII, with apodeme subrectangular, mesally constricted, darkened. Sternum IX (spiculum gastrale, Fig. 39c ) with basal plate bifurcate, forming two opposed rhombi, each nearly 1.6× longer than wide; apodeme 0.6× width of aedeagus in lateral view, 1.4× length of aedeagus. Tegmen ( Fig. 39d ) with tegminal apodeme 0.8× length of aedeagus; basal piece connate with tegminal plate; tegminal plate with bar-like mesal projection, posteriorly directed. Aedeagus in dorsal view ( Fig. 39e ) 3.4× longer than mesal width, lateral margins subparallel; apex ( Fig. 39f ) rounded; in lateral view ( Fig. 39g ) dorsally convex, 4.7× longer than mesal width. Endophallus with pair of subapical sclerotized plates closing the ostium. Aedeagal apodemes slightly longer than aedeagus.

Intraspecific variation. The length (pronotum and elytra) ranges from 4.0 to 5.0 mm, the width from 2.0 to 2.9 mm. Color varies from the typical pattern, to discal dark brown followed by a black fascia from humerus to declivity with remaining lateral and apical areas pale, to uniform dark brown.

Remarks and comparative notes. This species is very close to C. femoratus , which has a similar, markedly striate pronotum; the pronota of C. strigicollis and C. cornelli display discrete punctures within the striolae. Males of C. femoratus have the foretibiae with outer margin straight, inner margin with a large triangular tooth, and the apex rounded; while C. tibialis has the foretibia curved on both margins, on the inner margin extremely bent with notches and tubercles and the apex straight. Females of this species have a ventral process on the apex of the foretibia, not present in C. femoratus and the elytra are lighter in color than the pronotum in C. tibialis .

Range. Known only from the type locality, Florence, SC.

Materials examined. On hand for this study were 31 specimens, 17 males and 14 females.

Holotype female (in CASC on long-term loan to CWOB), “SC, Darlington Co., Florence, National Cemetery , 8-I-2005, C. W. O’Brien & R. H. Turnbow, berlese sifted mixed hardwood & longleaf pine litter”.

Paratypes. SC, Florence , Jan. 1938 (6) ; same except 14 Feb 1938 [no collector] (ALLOTYPE MALE ( CUAC), and two paratypes) ; same except 14-II-1938 (3); 25 Jan 1938 (4), 29 Jan 1938 (3), 3 Mch 1938 (11), F. F. Bondy, Soil Shaker (all from Clemson University Arthropod Collection) . Paratypes are in the following collections: CASC, CUAC, CWOB, JCCC, SCSM, and USNM.

Etymology. This epithet is from the Latin adjective tibialis (= of the tibia), and refers to the strangely formed fore- and midtibiae of the male.

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 16-23. Legs of Cercopeus species. 16) Left midfemur, C. femoratus, male, ventral view. 17) Left foretibia, C. alexi, male, lateral view. 18) Left foretibia, C. tibialis, male, lateral view. 19) Right foretibia, C. cornelli, male, ventral view. 20) Right foretibia, C. chrysorrhoeus, female, dorsal view. 21) Left foretibia, C. maspavancus, female, dorsal view. 22) Right foretibia, C. femoratus, female, dorsal view. 23) Left foretibia, C. tibialis, female, lateral view.

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.