Sternacutus brunneus, Vlasak & Santos-Silva, 2022

Sternacutus brunneus View in CoL sp. nov.

( Fig. 35-39)

ZooBank:http://zoobank.org/ 94C0A802-5DFA-407A-BA00-878D5922A5FD

Holotype, ♂, ECUADOR, Pichincha: 1,300 m, Nanegal, 27.IX.2021, J. Vlasak leg. ( MZSP).

Paratypes, 1 ♂ and 3 ♀, same data as holotype ( JVCO) .

Description of the holotype

Coloration. – Head capsule dark brown dorsally and laterally, light brown ventrally; ventral mouthparts reddish brown, except palpomeres black with reddish-brown apex; anteclypeus brown; anterior third of labrum yellowish brown; scape dark orangish brown, with brown apex; pedicel mostly brown; antennomere III orangish brown with reddish-brown apex; antennomeres IV-VIII orangish brown basally (this area gradually narrower toward VIII), gradually orangish brown toward brown apex; antennomeres IX -X orangish brown on basal half, dark brown on apical half; antennomere XI dark brown. Pronotum mostly brown, with sides of posterior seventh orangish brown, with large longitudinal dark-brown macula on each side of middle, from anterior to posterior seventh. Sides of prothorax mostly brown, with irregular lighter areas. Prosternum, prosternal process, mesoventrite, mesoventral process, and center of metaventrite orangish; mesanepisternum, mesepimeron, and metanepisternum brown; sides of metaventrite brownish. Elytra mostly brown, with irregular dark-brown areas, except orangish-brown sides of posterior half and apex. Coxae and trochanters pale yellow, metacoxae partially brownish; pro- and mesofemora pale yellow on peduncle, dark brown on club; metafemora pale yellow on peduncle, femoral club orangish brown ventrally and laterally, except dark-brown apex, brownish on basal 2/3 of dorsal surface, dark brown on apical third; tibiae blackish, except orangish brown basal 3/4 of ventral surface of protibiae, basal 2/3 of ventral surface of mesotibiae, and entire ventral surface of metatibiae; tarsi blackish. Ventrites yellowish brown with irregular brownish areas interspersed.

Head. – Frons abundantly, minutely punctate; with abundant dark yellowish-brown pubescence not obscuring integument, pubescence lighter toward clypeus and centrally toward antennal tubercles, yellowish close to eyes; with short, decumbent, thick white setae interspersed; with one long, erect dark seta on each side close to eyes. Vertex with abundant dark yellowish-brown pubescence partially obscuring integument, with lighter pubescence on narrow area close to eyes, except glabrous median groove. Area behind eyes with abundant yellowish pubescence, except glabrous area close to prothorax behind lower eye lobes. Genae with abundant light yellowish-brown pubescence not obscuring integument, except glabrous apex and area close to clypeus, with a few long, erect dark setae interspersed. Antennal tubercles with abundant dark yellowish-brown pubescence not obscuring integument, pubescence lighter apically. Wide central area of postclypeus with somewhat abundant, bristly dull yellowish-brown pubescence not obscuring integument, pubescence absent centrally, with short white setae interspersed; with one very long, erect seta on each side near frons, seta black basally, gradually yellowish toward apex; with long, decumbent yellowish setae close to anteclypeus, setae sparse centrally, abundant laterally. Sides of postclypeus glabrous. Posterior 2/3 of labrum with sparse yellowish pubescence and long, erect setae of same color interspersed; anterior third glabrous, except anterior margin with fringe of yellowish-brown setae. Gulamentum smooth, glabrous, except narrow depressed anterior region with somewhat abundant yellowish pubescence. Distance between upper eye lobes 0.19 times distance between outer margins of eyes; in frontal view, distance between lower eye lobes 0.48 times distance between outer margins of eyes. Antennae 2.6 times elytral length, reaching elytral apex at basal quarter of antennomere VI. Scape with abundant yellowish-white pubescence not obscuring integument dorsally and laterally, and abundant whitish pubescence ventrally not obscuring integument. Pedicel with abundant pubescence not obscuring integument, pubescence yellowish white on base of dorsal surface, whitish on remaining surface; with one long, erect, thick yellowish-brown seta ventrally. Antennomeres III-XI with abundant whitish pubescence not obscuring integument; antennomere III with a few short, erect, thick, both yellowish-brown and dark-brown setae ventrally; antennomere IV with one short, erect, thick dark seta ventrally, and a few similar setae on apex; antennomere V with a few short, thick dark setae apically.

Antennal formula based on length of antennomere III:

– Scape = 0.76. – Pedicel = 0.12. – IV = 0.81. – V = 0.69. – VI = 0.67. – VII = 0.62. – VIII = 0.62. – IX = 0.59. – X = 0.57. – XI = 0.52.

Thorax. – Prothorax wider than long; with well-marked anterior constriction; sides slightly rounded, gradually widened from anterior constriction to lateral tubercle; short area behind lateral tubercle slightly convergent toward posterolateral angles; lateral tubercle conical with apex slightly directed backward. Pronotum with one slight elevated gibbosity on each side of central area (corresponding to the dark-brown maculae), and slightly elevated gibbosity centrally; somewhat abundantly, coarsely punctate, punctures coarser near posterior margin, except smooth anterior constriction, sides of area close to posterior margin, and central gibbosity; with longitudinal yellowish-white pubescent band centrally, absent on central gibbosity, and irregular yellowish-white pubescent areas, close to apex of lateral gibbosities, close to lateral tubercles of prothorax, and on sides of anterior third; remaining surface mostly with abundant brownish pubescence not obscuring integument, except orangish posterior area with sparse yellowish pubescence. Sides of prothorax with abundant yellowish-white pubescence partially obscuring integument. Prosternum and mesoventral process with abundant whitish pubescence not obscuring integument, pubescence slightly denser and more yellowish white on sides of prosternum, and sparser on posterior third of prosternal process; narrowest area of prosternal process 0.34 time procoxal width. Ventral surface of meso- and metathorax with dense whitish pubescence partially obscuring integument, except short, sparser pubescence on center of mesoventrite and entire mesoventral process; narrowest area of mesoventral process 0.38 times mesocoxal width. Scutellum with abundant light yellowish-brown pubescence not obscuring integument.

Elytra. – Centrobasal crest of elytra elevated, longer than metatarsomere I, with abundant, short dark-brown pubescence not obscuring integument ( Fig. 39); apex individually rounded; abundantly, coarsely punctate on anterior half, punctures gradually finer and sparser toward apex on posterior half; with two moderately distinct longitudinal carinae dorsally, outermost from base to posterior quarter, innermost from apex of centrobasal crest to posterior quarter; humeral carina moderately well marked from base to posterior third; with abundant yellowish-brown pubescence not obscuring integument, pubescence paler on light area, with yellowish-brown pubescent spots on humeral carina, pubescent spots gradually lighter toward posterior region; with yellowish pubescent spots on anterior half of dorsal carinae, and white pubescent spots on posterior half of dorsal carinae; posterior third with irregular whitish pubescent spots interspersed.

24. ♀, Tambillo. 25. ♀, Pasochoa. 26. ♂, Tambillo. 27. Holotype ♂, Quito.

Legs. – Femora with abundant whitish pubescence not obscuring integument, except dorsal surface and sides of femoral club with yellowish-brown pubescence, with short, thick, decumbent white setae interspersed. Protibiae with yellowish-brown pubescence, denser on anterior 2/3 of ventral surface, with short, decumbent white setae interspersed, and bristly dark-brown pubescence on posterior third of ventral surface. Mesotibiae with yellowish pubescence not obscuring integument on anterior 2/3 on dorsal and lateral surfaces, pubescence denser, whitish ventrally on anterior 2/3, with short, thick, decumbent white setae interspersed; dorsal surface of posterior third with short, erect, thick dark-brown setae; ventral surface of posterior third with bristly yellowish-brown pubescence. Dorsal surface of metatibiae with somewhat abundant, decumbent, thick white setae; ventral surface with abundant light yellowish-brown pubescence, pubescence bristly on posterior third; dorsal surface with sparse, thick, erect dark setae from middle to posterior third; sides of posterior half with moderately long, erect, thick light yellowish-brown setae. Dorsal surface of tarsomeres I with abundant white pubescence; tarsomeres II with white pubescence on basal region, this area gradually longer toward metatarsi, dark brown on remaining surface; tarsomeres III and IV with mostly dark-brown pubescence; tarsomeres V with white pubescence basally, dark brown on remaining surface; metatarsomere I distinctly longer than II-III together.

Abdomen. – Ventrites with abundant whitish pubescence partially obscuring integument. Apex of ventrite 5 notched.

Female. Similar to male, differing by shorter antennae, 2.3 times elytral length, reaching elytral apex at the apex of antennomere VI, by last tergite triangularly projected, surpassing the apex of ventrite 5 by about 2/3 the length of ventrite 3, and by apex of ventrite 5 truncate.

Dimensions (mm) (Holotype ♂ / paratype ♂ / paratypes ♀). – Total length, 6.60/6.40/5.70-6.50;

– Prothoracic length, 1.15/1.25/0.90-1.10;

– Anterior prothoracic width, 1.35/1.30/1.10-1.25;

– Posterior prothoracic width, 1.60/1.60/1.30 -1.55;

– Maximum prothoracic width, 2.00/2.05/1.60 -1.85;

– Humeral width, 2.30/2.40/2.00-2.30;

– Elytral length, 4.90/4.60/4.30- 4.95.

Etymology. – The specific epithet “brunneus ” (Latin, meaning brown) refers to the mostly uniform brownish color of this species.

Remarks. – The elytral pubescent pattern and the length of the centrobasal crest of the elytra make S. brunneus distinct from all other species currently placed in Sternacutus .