Plectromerus lingafelteri Micheli & Nearns, 2005

Micheli, Charyn J. & Nearns, Eugenio H., 2005, Two new species of Plectromerus Haldeman (Coleoptera: Cerambycidae) from the West Indies, Zootaxa 1028 (1), pp. 23-36 : 25-30

Plectromerus lingafelteri Micheli & Nearns , new species

Figs. 2a–c , 3a

Description. MALE. Length 5.5–7.2 mm, width 1.2–1.7 mm (measured across humeri). Small, narrow, subcylindrical. Head, antennae, and pronotum ferrugineus, with some areas of pronotum, clavate portion of femora, apex of tibiae, and underside usually much darker; scape underneath, palpi, base of distal four antennomeres, femoral pedicle, and tarsi testaceus; each elytron with a dark macula just beneath humerus, this sometimes reaching basal third, humeral angle pale; dorsum with three major macular regions ( Fig. 2a ) as follows: (1) basal third dark with posterior margin irregular, obliquely reaching suture, with another dark, oblique, narrow, irregular macula just beneath separated by a pale irregular fascia, and not reaching suture; (2) an irregular, median dark macula not reaching suture, partially interrupted by a narrow, pale longitudinal area, and bordered posteriorly by an oblique, pale fascia; and (3) apical third ferrugineus, anterior margin obliquely reaching suture. Head with front nearly flat, transverse, with a median, shallow line from between eyes to just beyond vertex, slightly concave between antennal tubercles, which are somewhat raised and widely separated. Surface feebly shining, microsculptured, with some fine wrinkles and irregular, shallow punctation. Pubescence short, pale, recumbent, sparse to moderately dense with a few scattered long, suberect hairs. Eyes prominent, transverse, subreniform. Antennae 11­segmented, slightly longer than body, impunctate; third antennomere subequal to scape, almost twice as long as fourth, fifth antennomere 1.3 longer than third, 2.6 longer than fourth, sixth to tenth becoming progressively shorter, eighth subequal to third, eleventh slightly longer than tenth, subequal to ninth; basal antennomeres subcylindrical, from fifth slightly flattened, apices of antennomeres 5–10 produced externally, more pronounced on antennomeres 7–10. Antennomeres feebly shining, clothed with fine, short, recumbent, pale pubescence with slightly longer, suberect hairs intermixed and antennomeres 2–6 ciliate beneath with coarse, moderately long, suberect, pale hairs. Pronotum subcylindrical, about 1.5–1.6 times as long as wide, widest at middle, slightly broader at base than apex, sides feebly inflated, broadly arcuately constricted at basal fifth, and a slight inflation just before apex; basal margin slightly arcuate, apical margin nearly straight; disk convex, slightly depressed posteriorly, sometimes with three feeble tumescences, one centrally on disk and two anterior to this one, one on each side (these are barely discernible in some specimens). Surface opaque, microsculptured, with fine, sparse punctures, each of these with a fine, short, pale hair; punctation much coarser and deeper laterally (as large as on base of elytra) and shining. Pubescence slightly denser towards margins; each side of pronotum with two long, suberect setae, one anterolateral, the other one discal at basal third. Scutellum small, rounded, almost as long as broad, shining, impunctate, with sparse, short pale pubescence. Elytra about 2.6 to 3 times as long as width at humeri, 2.5 to 3 times as long as pronotal length, about 1.5 broader basally than pronotom at widest (at middle); sides nearly parallel, very slightly sinuate around middle, evenly rounded to apex which is rounded; epipleural margin moderately sinuate. Disk slightly concave medially, subsuturally; base of each elytron slightly raised. Surface shining, except basal macula which is matte; punctation moderately dense, coarse, shallow at basal third, punctures becoming finer towards apex and sides, almost obsolete at apical third; each puncture with a short, fine pale hair (some appear to have fallen off). Underside with prosternum shining, slightly rugose, apical fourth impunctate and one irregular patch of coarse, deep punctures in front of each coxa ( Fig. 2b ); with sparse, short, fine, pale hairs; narrowest area of prosternal process between coxae about 0.17 to 0.2 as wide as coxal cavity, and about 0.3 the width of apex of process which is subtriangular with rounded corners. Mesosternum shining, impunctate, very sparsely clothed with short, fine, pale hairs. Mesepisternum with denser pubescence than mesosternum. Metasternum shining, sparsely and finely punctate, with short, pale, moderately dense pubescence, much sparser on centroposterior area, much denser at postero­lateral angles, and with very few longer, pale hairs intermixed. Metepisternum clothed with moderately dense pubescence, denser posteriorly. Abdomen shining, clothed with sparse, short, pale pubescence, and with a few longer, suberect pale hairs; fifth sternite broadly subtruncate, slightly longer than preceding sternite. Legs with femora pedunculate­clavate, meso­ and metafemora arcuate, shining, impunctate, clothed with sparsely to moderately densely, recumbent, short, pale pubescence; underside of each femoral club with a broad triangular tooth with posterior edge smooth, not serrate; tibiae slightly arcuate, sinuate though not strongly; clothed with moderately dense, fine, recumbent, pale pubescence, becoming longer and coarser apically. Genitalia see Fig. 3a.

FEMALE. Length 5.5–8.3 mm; width 1.2–1.9 mm (measured across humeri). Very similar to male except pronotal sides lacking coarse punctures and prosternum impunctate ( Fig. 2c ). Abdomen with terminal sternite evenly, broadly rounded.

Etymology. This species is dedicated to Steven Lingafelter, who collected most of the type material and made the trip to the Dominican Republic by the senior author possible, and whose friendship, guidance, and companionship are truly appreciated.

Types. Holotype, male, DOMINICAN REPUBLIC, Pico Duarte Trail, 3300 ft., Los Tablones , beating, 19°08.222'N, 70°27.736'W, 29 June 2004, S. Lingafelter ( USNM) . Allotype, female, DOMINICAN REPUBLIC, Pedernales Prov., PN Sierra Baoruco, Las Abejas, 18°09.011'N, 71°37.342'W, 1150 meters, 11 July 2004, blacklight, C. J. Micheli, coll. ( USNM) . Paratypes, 14 (all from the Dominican Republic ): 1 male, same data as holotype, except day coll. ( USNM) ; 2 males, Pico Duarte Trail, Ciénaga to Los Tablones , beating, 19°08.222'N, 70°27.736'W, 29 June 2004, C. J. Micheli ( JAMC) ; 1 male and 1 female, Pedernales Prov., PN Sierra Baoruco, Las Abejas , 1150 m, 18°09.011'N, 71°37.342'W, ex. dead log w/ white fungus, 11 July 2004, S. Lingafelter ( USNM) ; 2 males and 1 female, Pico Duarte Trail, 3300 ft., Los Tablones , blacklighting, 19°08.222'N, 70°27.736'W, 17 July 2004, S. W. Lingafelter ( USNM) ; 1 male, Pedernales Prov., 25.5 km N. Cabo Rojo, 12­21­V­1992, coll. M. C. Thomas ( FSCA) ; 1 female, Azua, East side of crest, Sierra Martín García , 7 km WNW Barrero, 18­21 N, 70­58W, 860m, 25­26 July 1992, C. Young, R. Davidson, S. Thompson, J. Rawlins, cloud forest adjacent to disturbed forest ( CMNH) ; 2 males, Prov. Hato Mayor, Par. Nac. Los Haitises , 01­02 Apr 1992, bosque humido, W. Sabana dl Mar, M. Ivie, D. Sikes, Lanier ( WIBF) ; 1 male, Barahona, 4.5 km. S Barahona, 22 May 1992, R. Turnbow ( RTPC) ; 1 male, Pedernales, 25.5 km. N Cabo Rojo, 21 May 1992, R. Turnbow ( RTPC) .

Discussion. The intensity and breadth of maculations seem to be variable among specimens. Some specimens are mostly ferrugineus without any very dark areas but with the described light elytral pattern.

This species can be distinguished from the presently known congeners by the combination of the following characters: the opaque, microsculptured, finely punctate pronotum, the smooth metafemoral tooth, and the elytral maculation. At first glance, P. lingafelteri resembles Plectromerus dentipes (Olivier) ( Fig. 1e ) but this species has a shiny pronotum, the metafemoral tooth is serrate, and the elytral apex is moderately subtruncate (rounded in P. lingafelteri ). Another species with a rather intricate elytral pattern is P. exis Zayas ( Fig. 1f–g ), but P. lingafelteri can be easily recognized by the shape and length of the pronotum, the length of the third antennomere, and the elytral punctation. In P. exis , the pronotum has a distinct tubercle in the center and the length is about 1.8 times the width (1.5 to 1.6 in P. lingafelteri ), the third antennomere is distinctly longer than the scape (subequal in P.lingafelteri ), and the elytral dark areas are opaque and microsculptured (not so in P. lingafelteri ).

Figures

FIGURE 1. a, Plectromerus distinctus (Cameron), holotype; b, Plectromerus serratus (Cameron), holotype; c, Plectromerus distinctus (Cameron), view of pronotum and base of elytron; d, Plectromerus serratus (Cameron), view of pronotum and base of elytron; e, Plectromerus dentipes (Olivier); f, Plectromerus exis Zayas; g, Plectromerus exis Zayas, holotype.

FIGURE 2. a–c, Plectromerus lingafelteri Micheli & Nearns, new species: a, holotype; b, closeup of prosternum, male; c, closeup of prosternum, female; d–h Plectromerus ramosi Micheli & Nearns, new species: d, holotype; e, closeup of prosternum, male; f, closeup of prosternum, female; g, lighter phenotype; h, closeup of fifth antennomere; i, Plectromerus serratus (Cameron), closeup of fifth antennomere of holotype.

FIGURE 3. Tegmen and parameres, ventral view: a, Plectromerus lingafelteri Micheli & Nearns, new species; b, Plectromerus ramosi Micheli & Nearns, new species.