Leptostylus bicolor, Heffern & Santos-Silva, 2023

Heffern, Daniel & Santos-Silva, Antonio, 2023, American fauna of Cerambycidae and Disteniidae (Coleoptera): new species, new records, and notes, Zootaxa 5296 (1), pp. 45-57 : 48-51

Leptostylus bicolor sp. nov.

( Figs 7–12 , 18 )

Description. Holotype female. Integument mostly black; ventral mouthparts brownish yellow, except maxillary palpomeres I–III and labial palpomeres I–II brown with brownish-yellow apex, and maxillary palpomere IV and labial palpomere III black with brownish-yellow apex; anteclypeus mostly brownish orange; posterior half of labrum dark brown and anterior half yellowish (more brownish yellow depending on light intensity); scape, pedicel, and antennomere III dark brown, slightly lighter on some irregular areas; antennomere IV dark brown except reddishbrown ring near base and another, slightly lighter near apex; antennomeres V–VI brown basally and centrally, central region slightly lighter, dark brown apically, and orangish brown on remaining surface; antennomeres VII–X dark brown basally and apically, orangish-brown on wide central region; antennomere XI with dark-brown ring basally and after middle, orangish brown between dark-brown rings and on apex. Apex of ventrites 2–4 fulvous. Basal 2/3 of tarsomere V reddish brown and apical third dark brown.

Head. Frons abundantly, very finely punctate; with dense, irregular, both yellowish and brown pubescence, obscuring integument on some areas, pubescence absent on median groove, and part of brown pubescence forming fragmented V-shaped band on superior half; with one long, erect brownish-yellow seta close to each eye. Vertex with dense yellowish pubescence with brown pubescent maculae interspersed, except glabrous diamond-shaped central area between antennal tubercles and upper eye lobes, and glabrous area close to prothorax. Area behind upper eye lobes with dense yellowish pubescence and brown pubescent maculae interspersed close to eye, glabrous close to prothorax. Area behind lower eye lobes with pubescence as behind upper eye lobes on superior half; inferior half with narrow yellowish pubescence close to eye, dense pubescent macula shapes as a greater-than sign fused with the former pubescent band, and sparse brownish pubescence between them; area close to prothorax glabrous. Genae slightly longer than length of lower eye lobe; with abundant yellowish pubescence partially obscuring integument, with large, irregular brown pubescent macula superiorly, except glabrous apex. Wide central area of postclypeus with dense, bristly yellowish pubescence close to frons, with somewhat long yellowish setae directed forward on narrow area close to anteclypeus, and one long, erect seta on each side, seta black basally, gradually yellowish toward apex. Sides of postclypeus glabrous. Labrum with somewhat abundant yellowish pubescence on posterior half, with long, erect setae interspersed, erect setae brown basally, gradually yellowish toward apex; anterior half glabrous, except fringe of pale yellow setae on anterior margin. Outer side of mandibles triangularly depressed on basal half, with dense yellow pubescence, and one long, erect seta interspersed, seta black basally, gradually yellowish toward apex; remaining surface glabrous. Antennal tubercles with abundant pubescence, mostly brownish frontally, mostly yellowish on remaining surface. Distance between upper eye lobes 0.28 times distance between outer margins of eyes; in frontal view, distance between lower eye lobes 0.61 times distance between outer margins of eyes. Antennae 1.6 times elytral length, reaching elytral apex at apex of antennomere VIII. Scape with abundant brownish pubescence not obscuring integument dorsally and laterally, with irregular, whitish pubescent maculae interspersed laterally and most of basal half of dorsal surface, and irregular yellowish pubescent maculae interspersed on posterior half of dorsal surface; ventral surface mostly with abundant whitish pubescence not obscuring integument. Pedicel with abundant brown pubescence not obscuring integument, with yellowish pubescence interspersed on some areas and one long, erect yellowish seta ventrally. Antennomeres III–IV with abundant dark-brown pubescence, darker and denser apically, and irregular, partially fragmented white pubescent rings interspersed. Antennomeres V–XI with dense white pubescence on light areas and abundant dark-brown pubescence on dark areas, pubescence more yellowish brown on center of V. Antennal formula based on length of antennomere III: scape = 1.05; pedicel = 0.09; IV = 0.78; V = 0.42; VI = 0.35; VII = 0.31; VIII = 0.29; IX = 0.28; X = 0.26; XI = 0.22.

Thorax. Prothorax wider than long; sides with large, rounded protuberance about middle; anterior and posterior constrictions well marked. Pronotum with five, moderately elevated gibbosities, dorsally convex, two on each side between the constrictions, subfused, posterior one less elevated, another centrally, elliptical, located between middle and posterior constriction; with transverse row of coarse punctures on each side near anterior margin, continuing longitudinally to posterior constriction, bordering the central gibbosity, and transverse, sinuous row of coarse punctures about middle, crossing area between the two lateral gibbosities; sides of anterior third with somewhat coarse, sparse punctures; with transverse row of coarse punctures near posterior margin, punctures much larger than remaining ones; gibbosities with abundant dark-brown pubescence not obscuring integument, dark pubescence on posterolateral gibbosity continuing longitudinally toward posterior margin; area between posterior margin of central gibbosity and posterior margin with sparse yellowish-brown pubescence; center with dense yellowish-white pubescence, bifurcate and bordering central gibbosity toward posterior margin; area close to sides of prothorax with dense patches of pale-yellow pubescence with abundant areas with sparser pale-yellow pubescence interspersed, from anterior margin to posterior constriction, except rounded blackish pubescent spot behind lateral protuberance of prothorax; area between sides of posterolateral gibbosity and lateral yellowish-white pubescence with transverse, irregular yellowish-brown pubescent band; sides of area between beginning of posterior constriction and posterior transverse sulcus with abundant yellowish-brown pubescence not obscuring integument close to sides of prothorax, and dense pale-yellow pubescence with irregular brownish pubescent spots interspersed close to posterior dark-brown pubescent band; remaining pubescence on anterior 2/3 with dense yellowish-brown pubescence and abundant areas with sparser pubescence of same color interspersed; posterior sulcus glabrous; sides of posterior quarter with a few long, erect brownish setae. Sides of prothorax with sparse, coarse, shallow punctures; with abundant patches of yellowish pubescence and abundant, irregular areas with somewhat sparse yellowish-brown pubescence interspersed. Prosternum with abundant whitish pubescence not obscuring integument, pubescence slightly yellower laterally. Prosternal process with abundant whitish pubescence not obscuring integument; narrowest area 0.33 times procoxal width. Mesoventrite with sparse yellowish-white pubescence centrally, and dense pale-yellow pubescence with abundant areas with sparser pubescence interspersed laterally. Mesanepisternum and mesepimeron with dense yellowish pubescence and abundant areas with sparser yellowish-brown pubescence interspersed. Mesoventral process with abundant whitish pubescence not obscuring integument. Metanepisternum and sides of metaventrite with dense yellowish-white pubescence and abundant areas with sparser dark-brown pubescence interspersed; remaining surface of metaventrite with abundant whitish pubescence not obscuring integument. Scutellum with dense, small yellowish-white pubescent macula on anterolateral base, somewhat dense pale-yellow pubescent macula anterocentrally, yellowish-white pubescence not obscuring integument on remaining central region, and yellowish-brown pubescence on remaining surface, yellowish-brown pubescence slightly denser on middle of sides.

Elytra. Somewhat abundantly, coarsely punctate on anterior third, punctures gradually finer, sparser on posterior 2/3; centrobasal crest slightly elevated, with three slightly elevated tubercles dorsally, anterior one less elevated and without tuft of setae dorsally, posterior ones with dense tuft of erect brownish setae ( Fig. 9 ); area between centrobasal crest and suture with two slightly elevated tubercles with dense, erect tuft of brownish setae; with three, slightly elevated longitudinal carinae dorsally, subfused posteriorly, with sparse row of tubercles on them, dorsal surface of each tubercle with dense tuft of setae, setae brownish on its anterior half ( Fig. 11 ), dark brown on its posterior third ( Fig. 12 ); pubescence forming complex design: anterior quarter of dorsal surface with yellowish pubescence and abundant, irregular areas with yellowish-brown or pale-yellow pubescence interspersed, with small, irregular white pubescent spot near suture and scutellum, irregular, transverse, fragmented white pubescent band laterally on apex of anterior fifth, oblique yellowish-brown pubescent band between posterior tubercle of centrobasal crest and posterior tubercle near suture; area of dorsal surface between anterior quarter and area slightly after middle mostly with abundant yellowish-brown pubescence not obscuring integument, with irregular, dense yellowish pubescent maculae interspersed, yellowish pubescence forming oblique band close to apex of centrobasal crest and innermost lateral tubercle on anterior quarter, except longitudinal, fragmented white pubescent band near suture, this band narrower and continuing toward apex; posterior third with transverse pubescent band, pubescence pale yellow from epipleural margin to middle of dorsal surface, white, inverted V-shaped toward area near suture; posterior third with abundant, somewhat yellowish-brown pubescence not obscuring integument and dense, irregular yellowish pubescence interspersed, yellowish pubescence forming oblique band on posterior fifth; area surrounding innermost tubercles on posterior quarter of dorsal surface with somewhat dense dark-brown pubescence; sides with dark-brown pubescence close to humerus and apex of anterior third, and remaining surface with dense yellowish pubescence, slightly more yellowish-brown from middle, except epipleural margin with dashes of dense yellowish and dark-brown pubescence. Apex somewhat narrowly rounded. Legs. Femoral peduncle with abundant, both brownish and yellowish-white pubescence not obscuring integument; femoral club with abundant yellowish-brown pubescence not obscuring integument, and abundant, irregular areas with dense yellowish-white pubescence, distinctly yellower from middle. Tibiae mostly with abundant dark pubescence not obscuring integument, with irregular rings of dense whitish pubescence on apex of basal third, base of posterior third, and apex, except posterior third of ventral surface with dense, bristly yellowish-brown pubescence, and posterior third of dorsal surface of mesotibiae with abundant, short, erect blackish setae. Basal half of dorsal surface of tarsomeres with somewhat abundant whitish pubescence, remaining surface with dark pubescence.

Abdomen. Ventrites 1–4 with abundant dark-brown pubescence not obscuring integument, and abundant, irregular areas with dense whitish pubescence interspersed, except glabrous apex of 2–4; ventrite 5 mostly with abundant yellowish-white pubescence, and large areas with dark pubescence interspersed laterally. Apex of last tergite with dense fringe of pale-yellow setae.

Dimensions (mm). Total length, 10.10; prothoracic length, 2.00; anterior prothoracic width, 2.30; posterior prothoracic width, 2.95; maximum prothoracic width, 3.25; humeral width, 4.55; elytral length, 7.30.

Type material. Holotype female from PANAMA, Bocas del Toro: Fortuna Cabins , 8.7814ºN 82.1909ºW, UV lights, 23–30.V.2022, E.G. Riley leg. ( TAMU).

Etymology. The name of this species refers to the presence of two colors.

Remarks. Leptostylus bicolor sp. nov. is similar to L. pygialis Bates, 1872 ( Figs 13–17 ) but differs as follows: lower eye lobes about as long as genae ( Fig. 10 ); pronotal punctures on the posterior region coarser ( Fig. 18 ); punctures on the anterior third of the elytra coarser ( Fig. 7 ); transverse pubescent band after middle of the elytra wider, yellowish toward epipleural margin and inverted V-shaped white pubescent macula near suture ( Fig. 7 ); posterior quarter of the elytra with dark-brown pubescent band dorsally ( Fig. 7 ); and prosternal process slightly wider, 0.33 times procoxal width ( Fig. 8 ). In L. pygialis the lower eye lobes are longer than genae ( Fig. 16 ); pronotal punctures on the posterior region are finer ( Fig. 17 ), punctures on the anterior third of the elytra finer ( Fig. 13 ), transverse pubescent and after middle of the elytra slender, entirely white, not inverted V-shaped near suture ( Fig. 13 ), dorsal surface of the posterior quarter of the elytra with pale-yellow pubescent macula, bordered with white pubescence anteriorly ( Fig. 13 ), and prosternal process slightly narrower, 0.28 times procoxal width ( Fig. 14 ). Leptostylus bicolor sp. nov. differs from L. laevicauda chiriquinus Bates, 1885 (see photograph on Bezark 2023) by the body stouter (slender in L. laevicauda chiriquinus ) and by the white pubescent band on the posterior half of the elytra forming inverted V-shaped pubescent macula near suture (entirely oblique in L. laevicauda chiriquinus ); it also differs from L. cristulatus Bates, 1872 (see photograph on Bezark 2023) by the absence of large yellowish-white pubescent macula on sides of the posterior half of the elytra (present in L. cristulatus ), and by the centrobasal crest with three tubercles dorsally (four in L. cristulatus ).

Figures

FIGURES 7–12. Leptostylus bicolor sp. nov., holotype female: 7) Dorsal habitus; 8) Ventral habitus; 9) Lateral habitus; 10) Head, frontal view; 11) Tufts of setae on anterior half of the elytra; 12) Tufts of setae on posterior third of the elytra.

FIGURES 13–18. Leptostylus spp. 13–17) Leptostylus pygialis Bates, 1872, female: 13) Dorsal habitus; 14) Ventral habitus; 15) Lateral habitus; 16) Head, frontal view; 17) Punctures on the posterior region of the pronotum. 18) Leptostylus bicolor sp. nov., holotype female, punctures on the posterior region of the pronotum.