Compsibidion volcanense Vlasak and Santos-Silva, 2024

Compsibidion volcanense Vlasak and Santos-Silva , new species

( Fig. 1–6 View Figures 1–6 , 42–43 View Figures 38–43 )

Description. Holotype female ( Fig. 1–6 View Figures 1–6 ). Head capsule blackish, except reddish-brown sulcus on sides of frontal plate and posterior half of gulamentum; mouthparts mostly dark reddish brown ventrally, except apical maxillary and labial palpomeres dark brown with apex partially dark yellowish brown; anteclypeus brown except light-brown sides; labrum dark brown posteriorly, gradually lighter toward anterior margin, except light-brown sides; scape dark brown except dark reddish-brown apex of dorsal surface; pedicel and antennomeres III–XI orangish. Pronotum dark brown close to anterior margin, dark orangish brown on remaining anterior 2/3, except dark-brown anterolateral and central tubercles, orangish on posterior third, except dark orangish brown posterolateral tubercles. Sides of prothorax blackish close to anterior margin and large, oblique band from area close to anterior margin to procoxal cavity; remaining surface orangish brown. Posterior half of prosternum dark brown laterally, dark orangish brown on remaining surface, except reddish-brown central area and dark-brown area close to procoxal cavities; anterior half dark brown close to anterior margin and laterally, blackish close to posterior half, reddish brown on remaining surface. Prosternal process dark brown on sides of anterior 3/4, orangish brown on remaining surface. Ventral surface of meso- and metathorax orangish brown except margins of mesoventrite and mesoventral processes close to mesocoxal cavities, and dark reddish-brown margins of metaventrite. Scutellum orangish brown. Elytra pale yellow, slightly irregularly brownish on some areas, except large, transverse hourglass-shaped macula on posterior third, from suture to epipleural margin, dark-brown outer apical spine, and brown sutural region on apical fifth. Profemora reddish brown except orangish-brown apical fifth and dark-brown ventral surface of femoral peduncle, dark area partially reaching sides; mesofemora orangish brown with irregular brownish areas; metafemora orangish brown about basal half, dark brown on remaining surface; tibiae orangish brown; tarsi dark orangish brown. Abdominal ventrite 1 orangish brown on basal half, entire lateral areas, and close to apical margin, dark brown on remaining surface; ventrites 2–5 dark brown, except orangish-brown apex of ventrites 2–4.

Head. Frons abundantly, coarsely rugose-punctate, especially close to median groove, except moderately coarsely punctate area close to eyes; frontal plate abundantly, transversely rugose-punctate; with deep sulcus on each side of frontal plate and between it and postclypeus; with moderately sparse whitish pubescence, absent on anterocentral area of frontal plate. Area between antennal tubercles and posterior margin of eyes moderately abundantly and coarsely punctate, except smooth posterocentral region; with whitish pubescence not obscuring integument, pubescence denser laterally, sparser centrally between antennal tubercles and upper eye lobes, mostly absent centrally. Remaining surface of vertex transversely rugose centrally, smoothly rugose-punctate laterally; glabrous. Area behind upper eye lobes coarsely rugose-punctate close to vertex and prothorax, smooth on remaining surface close to eye; with whitish pubescence not obscuring integument close to vertex, glabrous on remaining surface. Area behind lower eye lobes, moderately abundantly, coarsely punctate close to eye, abundantly, finely rugose-punctate close to prothorax, gradually subsmooth toward ventral surface; with sparse whitish pubescence and long, erect brownish setae interspersed close to eye, glabrous on remaining surface. Genae somewhat abundantly and coarsely punctate except smooth apex; with sparse whitish pubescence except glabrous smooth area. Antennal tubercles somewhat abundantly, rugose-punctate basally, abundantly finely punctate centrally, smooth apically; with sparse whitish pubescence on punctate area, glabrous on smooth area. Maxillary palpomeres IV and labial palpomeres III securiform. Outer surface of mandibles abundantly, rugose-punctate on basal 2/3, smooth on apical third; with sparse whitish pubescence and long, erect yellowish-brown setae interspersed on basal 2/3, glabrous on apical third. Gulamentum smooth, glabrous on posterior half; area of anterior half close to posterior half sparsely, coarsely punctate, and sparse whitish pubescence laterally; remaining region of anterior half coarsely rugose-punctate, with sparse, bristly, short whitish setae and a few long, erect setae of same color interspersed. Wide central area of postclypeus with moderately abundant whitish pubescence not obscuring integument close to frons, and moderately abundant, short, decumbent whitish setae directed forward close to anteclypeus. Sides of postclypeus smooth, glabrous. Labrum smooth laterally, moderately abundantly, coarsely punctate centrally; glabrous laterally; remaining surface with moderately sparse, both short and long whitish setae and one long, erect yellowish-brown seta on each side. Distance between upper eye lobes 0.21 times distance between outer margins of eyes; in frontal view, distance between lower eye lobes 0.42 times distance between outer margins of eyes. Antennae 2.05 times elytral length, reaching elytral apex at base of antennomere IX. Scape subpiriform; longitudinally sulcate on basal 2/3 of dorsal surface; abundantly, finely punctate on dorsal and lateral surfaces of basal 2/3, smooth on apical third of dorsal surface, sparsely finely punctate on sides of apical third, almost smooth ventrally; with moderately abundant whitish pubescence not obscuring integument on basal 2/3 of dorsal and lateral surfaces, sparse whitish pubescence on sides of apical third, smooth, glabrous on apical third of dorsal surface, mostly glabrous ventrally; with sparse, moderately short, thick yellowish-brown setae interspersed dorsally and laterally, and long, erect yellowish setae interspersed ventrally. Pedicel with sparse whitish pubescence dorsally and laterally, pubescence absent ventrally; with long, erect yellowish setae interspersed dorsally and ventrally. Antennomeres III–XI with abundant whitish pubescence not obscuring integument; III– VIII longitudinally carinate dorsally; III–VI with long, erect yellowish setae interspersed ventrally; III with a few long, erect yellowish setae interspersed dorsally; IV–VI with a few long, erect setae on dorsal apex; VII–X with a few long, erect yellowish setae on apex of dorsal and ventral surfaces; III–IV with small asperities on ventromedial margin. Antennal formula based on length of antennomere III: scape = 0.60; pedicel = 0.18; IV = 0.51; V = 0.77; VI = 0.88; VII = 0.83; VIII = 0.80; IX = 0.77; X = 0.65; XI = 0.70.

Thorax. Prothorax distinctly longer than wide; anterior constriction moderately well marked; sides slightly rounded, widened centrally, slightly concave between anterior constriction and widened area and between widened area and posterolateral angles. Pronotum with large, oblique tubercle with rounded apex on each side from anterior third to middle, moderately small tubercle with rounded apex on each side of posterior third, and large, subelliptical central tubercle with rounded apex, located between anterior and posterior thirds; with a few coarse punctures, absent on tubercles; with abundant yellowish pubescence not obscuring integument on anterior third, posterior third, and sides of part of central third, except glabrous apex of posterolateral tubercles and narrow area close to anterior margin, and sparse yellowish pubescence on remaining central third, except smooth tubercles; with long, erect light yellowish-brown setae interspersed. Sides of prothorax with abundant yellowish pubescence on posterior 2/3 close to pronotum, except subglabrous area close to posterior margin, sparse whitish pubescence on remaining posterior 2/3, glabrous on most of anterior third; with long, erect light yellowish-brown setae interspersed, erect setae more abundant on anterior half. Prosternum with moderately dense U-shaped pubescent area on center of posterior half; remaining surface with very sparse whitish pubescence; with long, erect light yellowish-brown setae close to base of prosternal process; posterior half sparsely, moderately coarsely punctate; anterior half transversely striate close to posterior half, very sparsely, minutely punctate on remaining surface. Prosternal process with abundant whitish pubescence not obscuring integument, except sparse, minute whitish pubescence on apical area; narrowest area 0.14 times procoxal width. Ventral surface of meso- and metathorax with abundant whitish pubescence not obscuring integument laterally, pubescence distinctly sparser centrally, absent on part of meso- and metaventrite. Sides of mesoventral process concave, making apical area distinctly widened; apex distinctly notched centrally; narrowest area 0.53 times mesocoxal width. Scutellum with abundant yellowish pubescence not obscuring integument, pubescence distinctly denser on margins. Elytra. Moderately abundantly, shallowly, coarsely punctate on anterior 3/4, punctures finer and sparser on apical quarter; with small asperities on anterior quarter and close to suture on anterior 2/3; apex obliquely truncate, outer angle forming long spine and sutural angle shortly projected; with moderately sparse, long, erect light yellowish-brown setae throughout, and very sparse, minute whitish setae throughout. Legs. Femora with abundant whitish pubescence not obscuring integument, except sparse pubescence on ventral surface of profemora; with long, erect, light yellowish-brown setae interspersed; apices of profemora not projected; apices of mesofemora with short triangular projection ( Fig. 5 View Figures 1–6 ); apex of metafemora with distinct triangular projection, almost spiniform ( Fig. 6 View Figures 1–6 ). Tibiae with abundant whitish pubescence not obscuring integument, except ventral surface of protibiae with dense, bristly yellowish-brown pubescence, and ventral apex of meso- and metatibiae with yellowish-brown pubescence; with long, erect yellowish-brown setae interspersed; meso- and metatibiae with small asperities; all tibiae longitudinally carinate, carina becoming indistinct from middle on outer surface and from basal third on inner surface. Dorsal surface of tarsi with sparse whitish pubescence and long, erect yellowish setae interspersed; metatarsomere I as long as II–III together.

Abdomen. Ventrites with abundant whitish pubescence not obscuring integument, pubescence absent on apex of ventrites 1–4, sparse centrally on remaining central area of ventrite 1, almost absent on remaining surface of ventrites 2–4; with long, erect yellowish setae interspersed; apex of ventrite 5 rounded.

Male ( Fig. 42–43 View Figures 38–43 ). Similar to female, differing: the antennae longer, 2.55 times elytral length, reaching elytral apex at base of antennomere VIII; and antennomeres III–IV tumid, especially III. Additionally, in the paratype male the dark area on the posterior region of elytra is distinctly wider and not hourglass-shaped, and the ventral surface of the abdomen is entirely dark.

Dimensions (mm) (holotype female/ paratype male). Total length, 11.00/10.60; prothoracic length, 2.20/2.35; anterior prothoracic width, 1.35/1.40; posterior prothoracic width, 1.40/1.45; maximum prothoracic width, 1.45/1.55; humeral width, 2.00/2.15; elytral length, 6.95/6.85.

Type specimens. Holotype female from BOLIVIA, Santa Cruz: Refug. los Volcanes , 1100 m, at lights, 19–21 Nov 2023, J. Vlasak leg. ( MZSP, formerly JVCO) . Paratype male from BOLIVIA, Santa Cruz: Achiras, 1400 m, at lights, 21–22 Nov 2024, J. Vlasak leg. ( JVCO).

Etymology. The name “volcanense ” refers to the type locality, the Refugio los Volcanes in Bolivia.

Remarks. Compsibidion volcanense new species is similar to C. mysticum Martins, 1969 , but differs as follows: upper eye lobes with four rows of ommatidia; connection between eye lobes with two rows of ommatidia; frons mostly transversely striate; and scape longitudinally sulcate on basal two-thirds of dorsal surface. In C. mysticum , the upper eye lobes have three rows of ommatidia, connection between eye lobes have a single row of ommatidia, sometimes, eyes completely divided, frons not transversely striate, and the scape not longitudinally sulcate dorsally, if present, the sulcus is very shallow and present only on basal quarter. Although some parts of the body are colored differently in the two species (e.g. scape, base of elytra, femora), we prefer not to use the chromatic pattern as a differential feature. This is because coloration is often at least somewhat variable in some species of Tropidini , including C. mysticum .

Unfortunately, the holotype was partially damaged by anobiids during the transportation from the United States of America to Brazil.

Lamiinae Latreille, 1825 Acanthocinini Blanchard, 1845