Cacostola thomasorum Wappes and Santos-Silva, 2019

Wappes, James E. & Santos-Silva, Antonio, 2019, New species and taxonomic notes for Cacostola Fairmaire and Germain, 1859 (Coleoptera: Cerambycidae: Lamiinae: Onciderini), Insecta Mundi 741 (741), pp. 1-20 : 8-10

Cacostola thomasorum Wappes and Santos-Silva , new species

( Fig. 24–27 )

Description. Male. Integument mostly dark brown, almost black on some areas; mouthparts dark reddish-brown, except palpomeres black with reddish-brown apex; anteclypeus yellowish-brown; basal area of antennomeres V–XI reddish-brown, gradually lighter toward distal segments.

Head. Frons finely, abundantly punctate; with dense yellowish-brown pubescence obscuring integument, except sparsely pubescent close to clypeus on each side of median groove, and dark yellowish-brown pubescent on each side near base of antennal tubercles. Vertex finely, abundantly punctate; area between antennal tubercles and beginning of upper eye lobes with dense yellowish-brown pubescence; central area with inverted U-shaped brown pubescent band in middle of area between upper eye lobes, not reaching prothoracic margin; remaining surface with pale yellow pubescence obscuring integument, with a few punctures exposed. Area behind eyes finely, abundantly punctate; with pale yellow pubescence partially obscuring integument. Genae 0.55 times length of lower eye lobe; finely, abundantly punctate, less so toward frons; with pale yellow pubescence obscuring integument on some areas (more yellowish-brown depending on light intensity), sparser close to frons. Antennal tubercles with inner projection distinctly elevated, wide, thick, with apex rounded, concave on the surface facing scape-ball; together somewhat U-shaped; sculpturing as on frons, distal area smooth; with pale yellow pubescence obscuring integument. Wide central area of postclypeus close to frons with dense yellowish-brown pubescence (lighter depending on light intensity), glabrous laterally and close to anteclypeus (with a few short, sparse setae laterally close to anteclypeus); with a few long brownish setae directed forward on sides of wide central area. Labrum with sparse yellowish-white pubescence close to anteclypeus, yellowish-brown pubescence laterally on inclined area, and fringe of yellow pubescence at anterior margin; with short, erect dark setae on sides of central area. Mandibles with pale yellow pubescence on basal 2/3 of outer surface. Distance between upper eye lobes 0.34 times length of scape; in frontal view, distance between lower eye lobes 0.93 times length of scape. Antennae 2.6 times elytral length, reaching elytral apex at basal quarter of antennomere VII. Scape gradually, slightly widened toward apex; with yellowish-white pubescence partially obscuring integument, with brownish and pale-yellow pubescence irregularly interspersed on some areas. Antennomere III with yellowish-white pubescence, with brownish pubescence irregularly interspersed on small areas; antennomere IV with yellowish-white pubescence on basal 3/4, brownish, with yellowish-white pubescence interspersed on distal quarter; antennomeres V–XI with yellowish-white pubescence on light area, brown on dark area; pedicel, antennomere III, and base of IV with short, sparse, erect, thick dark setae ventrally. Antennal formula (ratio) based on length of antennomere III: scape = 0.72; pedicel = 0.17; IV = 1.20; V = 1.17; VI = 1.12; VII = 1.02; VIII = 0.95; IX = 1.00; X = 0.95; XI = 1.15.

Thorax. Prothorax wider than long; nearly parallel-sided; posterior margin slightly sinuous. Pronotum coarsely, abundantly punctate; with yellowish-white pubescence not obscuring integument, slightly yellower on anterior third, slightly denser on posterocentral area. Sides of prothorax coarsely, abundantly punctate; with yellowish-white pubescence not obscuring integument. Prosternum coarsely, sparsely punctate; with sparse pale-yellow pubescence. Prosternal process with pubescence slightly denser than on prosternum; narrowest area 0.25 times width of procoxal cavity. Mesoventrite, mesepimeron, metanepisternum and metaventrite with abundant yellowish-white pubescence, not obscuring integument; mesanepisternum with pale yellow pubescence partially obscuring integument. Scutellum glabrous centrally, with yellowish-white pubescence not obscuring integument laterally. Elytra. Humeri slightly projected; sides slightly narrowed from humeri to posterior fifth, then more distinctly narrowed toward obliquely truncate apex; coarsely, abundantly punctate on basal third, gradually finer, sparser toward apex; with small pale yellow pubescent macula, between humeri and scutellum basally; with yellowishwhite pubescence not obscuring integument, more abundant, slightly yellower on posterior half, except longitudinal, fragmented white pubescent band from near base to distal third along center of dorsal surface, and dense, somewhat large yellowish-white pubescent macula near apex dorsally. Legs. Femora with yellowish-brown pubescence not obscuring integument, more yellowish-white basally on meso- and metafemora. Tibiae with pale yellow pubescence, gradually yellowish-brown, bristly toward apex, especially on meso- and metatibiae, and brownish pubescence interspersed on meso- and metatibiae.

Abdomen. Ventrites with pale yellow pubescence, denser laterally toward V, longer throughout toward V, and longitudinal, somewhat irregular tuft of dense yellow pubescence on each side of ventrites II–V. Apex of ventrite V slightly concave.

Dimensions (mm). Total length, 9.6; prothoracic length, 1.6; anterior prothoracic width, 1.8; posterior prothoracic width, 1.8; maximum prothoracic width, 1.9; humeral width, 2.6; elytral length, 6.9.

Type material. Holotype male from BRAZIL, Rondônia: 62 km SW Ariquemes (Fazenda Rancho Grande), 18.XI.1994, C.W. and L.B. O’Brien col. ( FSCA, formerly ACMT).

Remarks. The general appearance of Cacostola thomasorum sp. nov. resembles some species of Trestonia Buquet, 1859 . Dillon and Dillon (1946) defined Cacostola as follows: “Distinguished by the small, elongate, slender, parallel-sided form of body; elytra and pronotum usually with pale vittae; antennal tubercles well-separated, very prominent, armed with an erect tooth in both sexes; eye with lower lobe large; antennae with third segment sometimes curved, the fourth often longer than third; legs short; and the mesosternum elongate before process.” Still, according to Dillon and Dillon (1946), Trestonia is: moderate or small sized, elongate-oblong, rather slender; antennal tubercles prominent, well separated, in male produced into a long, robust tooth truncate at apex, in female tooth short and subacute; eyes with lower lobe oblong-ovate or oblong, one and one-half to more than twice height of gena; antennae one and one-third times body length in male, as long as body (or slightly longer) in female; antennomere III straight or feebly arcuate, IV either slightly shorter or slightly longer than third. Those features do not allow separating Trestonia from Cacostola and are not present in several species currently placed in the genus. We find a more reliable character is the scape, which is clavate in Trestonia versus being gradually widened toward the apex in Cacostola .

In Cacostola , C. thomasorum is slightly similar to C. cana Marinoni and Martins, 1982 (see photo of the holotype at Bezark 2019a), differing by the absence of a transverse white pubescent band on the base of the elytra (present in C. cana ), and having the elytral apex widely, obliquely truncate (distinctly narrower and nearly rounded in C. cana ). It also somewhat resembles C. nordestina Martins and Galileo, 1999 , but differs by the antennomeres not being distinctly annulate (antennal annulations very distinct in C. nordestina ), and elytra lacking large irregular orangish-brown areas (present in C. nordestina ).

Etymology. Named in appreciation of Michael C. Thomas, former Head Curator of Entomology at FSCA (recently deceased) and spouse Sheila for their many years of hosting visitors to FSCA and providing welcome hospitality to all of them.

Figures

Figures 20–27. Cacostola spp. 20–23) Cacostola howdenae, holotype male. 20) Dorsal habitus. 21) Ventral habitus. 22) Lateral habitus. 23) Head, frontal view. 24–27) Cacostola thomasorum, holotype male. 24) Dorsal habitus. 25) Ventral habitus. 26) Lateral habitus. 27) Head, frontal view.