Rosalba nona, Vlasak & Santos-Silva, 2025

Rosalba nona sp. nov.

( Fig. 3 -6)

ZooBank:https://zoobank.org/ D3CF7A3A-37D0-43E7-A3F8-871DA57D7CE4

Holotype, ♂, ECUADOR, Pichincha: El Septimo Paraiso Hotel , 1600 m, Mindo, 4 Jul 2023, J. Vlasak leg. ( MZSP, formerly JVCO).

Description of the holotype ( Fig. 3-6)

Coloration. –Head capsule dark brown; ventral mouthparts mostly dark orangish brown, except lighter apices of palpomeres; anterior half of labrum light brown; scape dark brown; pedicel brown; antennomere III orangish brown, slightly darker on apical third, except dark-brown dorsal area on posterior quarter;antennomeres IV-VII light orangish brown, exceptbrownish apical third; antennomeres VII-X orangish brown on basal quarter, dark brown on remaining surface; antennomere XI orangish brown on basal sixth, dark brown on remaining surface. Mandibles black. Prothorax dark brown, except prosternal process with irregular dark orangish-brown areas. Mesoventrite, mesanepisterna, and mesepimera dark brown. Mesoventral process orangish brown. Metanepisterna dark brown, except dark orangish brown posterior third. Metaventrite orangish brown, except dark orangish brown central area with two irregular blackish maculae on each side of metathoracic discrimen, and narrow dark-brown area close to meso- and metacoxal cavities. Scutellum orangish brown centrally, dark brown on remaining surface. Elytra dark brown on anterior sixth, this area projected backward close to suture and gradually narrowed toward epipleural margin; remaining anterior third orangish brown, more reddish brown in punctures, except narrow brown area close to suture; remaining elytral surface brown, gradually lighter toward apex, with irregular orangish areas on posterior third. Coxae mostly dark brown, procoxae with black area anteromedially. Trochanters mostly orangish. Profemora dark brown; mesofemora orangish basally, this area slightly longer ventrally, dark brown on remaining surface; metafemora orangish basally, about basal half of dorsal surface, most of basal half of sides, and apical area of dorsal surface, dark brown on remaining surface. Pro- and mesotibiae dark orangish brown about basal third, dark brown on remaining surface; metatibiae orange on basal 3/4, mostly dark brown on apical quarter. Tarsomeres I dark brown; II orangish brown with dark-brown apex; protarsomeres III orangish brown; meso- and metatarsomeres III irregularly, both dark brown and orangish brown; IV orangish brown; V orangish brown on basal 4/5, dark brown on apical fifth; claws orangish brown, gradually dark brown on apical quarter. Abdominal ventrites light yellowish brown with irregular dark-brown maculae.

Head. – Frons somewhat sparsely and coarsely punctate; with abundant yellowish pubescence not obscuring integument, except dense pale-yellow pubescence close to eyes and glabrous median groove; with a few long, erect dark-brown setae close to eyes. Area between antennal tubercles with dense pale-yellow pubescence, except glabrous median groove. Area close to eyes, dorsally and laterally with dense light yellowish-brown pubescent band; remaining surface of vertex and behind eyes with abundant brown pubescence not obscuring integument, except transverse light yellowish-brown pubescent band close to prothorax and on each side of median groove, and glabrous median groove; with a few long, erect dark-brown 1. Lepturdrys capixaba Monné et al, 2024, female (MZSP 67357) from Brazil (Paraná). 2. Eupogonius petulans Melzer, 1933 , male (MZSP 67361) from Brazil (São Paulo, São Paulo).

3. Dorsal habitus. 4. Ventral habitus. 5. Lateral habitus. 6. Head, frontal view.

setae interspersed on brown pubescent area behind lower eye lobes. Genae 0.27 times as long as lower eye lobe in frontal view; with abundant light yellowish-brown pubescence partially obscuring integument, except apex partially glabrous; with a few long, erect dark-brown setae interspersed laterally. Postclypeus with abundant yellowish pubescence partially obscuringintegument, except sidespartially glabrous; with long, erect dark-brown setae interspersed on wide central area, setae slightly lighter toward their apices. Labrum glabrous on posterior third, with abundant yellowish-white pubescence not obscuring integument about central third, glabrous about anterior third, except short fringe of golden setae on anterior margin; with long, erect dark-brown setae interspersed on pubescent area. About basal half of outer surface of mandibles with dense light yellowish-brown pubescence, with a few long, erect dark-brown setae interspersed; remaining surface glabrous. Distance between upper eye lobes 0.05 times distance between outer margins of eyes; in frontal view, distance between lower eye lobes 0.46 times distance between outer margins of eyes. Antennae 2.2 times elytral length, reaching elytral apex at apical third of antennomere VII. Scape with abundant light yellowish-brown pubescence not obscuring integument; with a few long, erect dark-brown setae intersperse on apical third of ventral surface. Pedicel with abundant yellowish-white pubescence not obscuring integument; with long, erect dark-brown setae interspersed ventrally. Antennomeres III-VI with somewhat abundant yellowish-white pubescence not obscuring integument; with long, erect dark-brown setae interspersed ventrally, setae moderately abundant on III; with sparse short, erect yellowish setae interspersed throughout. Antennomeres VII-XI with moderately abundant yellowish-white pubescence not obscuring integument on light integumental area and somewhat abundant dark-brown pubescence on dark integumental area, this area with short, decumbent yellowish-white setae interspersed; VII-VIII with a few long, erect dark-brown setae interspersed ventrally;IX-X with one long, erect dark-brown seta on ventral apex; XI with long, erect pale-yellow setae directed backward on apex.

Antennal formula (ratio) based on length of antennomere III:

– Scape = 0.96. – Pedicel = 0.20. – IV = 1.40. – V = 1.20. – VI = 1.16. – VII = 1.00. – VIII = 0.96. – IX = 0.96. – X = 0.80. – XI = 0.88.

Thorax. – Prothorax slightly wider than long; anterior and posterior constrictions narrow, well marked; sides subparallel-sided on anterior third, slightly widened centrally, without a distinct tubercle, then slightly concave toward posterolateral angles. Pronotum abundantly, coarsely punctate; with three longitudinal, narrow pale-yellow pubescent bands between constrictions, one centrally, another on each side, not close to sides of prothorax;with dense pale-yellow pubescence on anterior third close to sides of prothorax and irregular, longitudinal, narrow pale-yellow pubescent band laterocentrally; remaining surface with abundant dull yellowish-brown pubescence not obscuring integument; witha few long, erect dark-brown setae on sides. Sides of prothorax somewhat abundantly, coarsely punctate;with dense pale-yellow pubescence partially obscuring integument close to pronotum on anterior 2/3, somewhat abundant dull yellowish-brown pubescence not obscuring integumenton remaining surface, except glabrous anterior and posterior sulci. Prosternum somewhat abundantly and finely punctate laterally, punctures sparser and coarser centrally; with abundant pale-yellow pubescence not obscuring integument laterally and sparse pubescence of same color centrally. Prosternal process sparsely, coarsely punctate; with abundant pale-yellow pubescence not obscuring integument, pubescence more yellowish white close to apex; narrowest area 0.26 times procoxal width. Mesoventrite with sparse yellowish-white pubescence except abundant light yellowish-brown pubescence laterally. Mesanepisterna and mesepimera with abundant dark-brown pubescence not obscuring integument, with yellowish pubescence interspersed. Mesoventral process with abundant pale-yellow pubescence not obscuring integument; sides slightly concave; apex widely, slightly concave; narrowest area 0.39 times mesocoxal width; apex 0.52 times mesocoxal width. Metanepisterna and metaventrite with abundant pale-yellow pubescence partially obscuring integument, except center of metaventrite with pubescence slightlysparser and paler. Scutellum withlongitudinalpale-yellow pubescent band centrally, somewhat abundant light yellowish-brown pubescence not obscuring integument on sides of posterior half, and sparse, both brown and light yellowish-brown pubescence on remaining surface.

Elytra. – Subparallel-sided on anterior 3/4, convergent on posterior quarter; apex obliquely truncate; moderately sparsely, coarsely punctate on anterior half, punctures gradually sparser, finer toward apex on posterior half; dark anterior integumental area with somewhat abundant brownish pubescence not obscuring integument, except yellowish pubescence not reaching humerus basally, three short, longitudinal yellow pubescent bands, innermost not reaching base and the two outermost starting on base, and abundant pale-yellow pubescence not obscuring integument close to suture; orangish-brown area with dense yellowish-white pubescence, dorsal pubescence slightly yellower on three longitudinal pubescent bands and anterolaterally; remaining dark integumental area on anterior third with somewhat sparse yellowish-brown pubescence, except abundant pale-yellow pubescence close tosuture;area close to suture on posterior 2/3with abundant pale-yellow pubescence partially obscuring integument; inner area of posterior 2/3 of dorsal surface with dense pale-yellow pubescence, except two large areas with brownish pubescence not obscuring integument, one about middle of elytra, the other on posterior third, and subglabrous, very narrow band near suture, this area widened on posterior sixth, and irregular areas with brownish pubescence on remaining posterior sixth; remaining sides of surface with longitudinal dashed pale-yellow pubescent bands. With sparse, long, erect yellowish setae, especially on epipleural margin, and a few long, erect dark-brown setae on apical sixth.

Legs. – Coxae, trochanters, and femora with abundant yellowish pubescence not obscuring integument. Tibiae with abundant yellowish pubescence not obscuring integument on light integumental area and abundant light-brown pubescence on dark integumental area, except denser and bristly dark-brown pubescence on ventral surface of protibiae, yellowish-brown pubescence on ventral surface of meso- and metatibiae, dense and bristly light-brown pubescence on dorsal surface of mesotibiae, and partially yellowish pubescence on sides of metatibiae; protibiae with long, erect, thick dark-brown setae on apical 2/3 of dorsal surface and sides of apical quarter; meso- and metatibiae with moderately short, erect dark-brown setae on apical 2/3 of ventral surface; metatibiae with moderately short, erect dark-brown setae on dorsal surface. Dorsal surface of tarsomeres with moderately abundant yellowish-white pubescence not obscuring integument, pubescence sparser on IV-V, and appearing to be darker on some areas due to integumental color of tarsomere; tarsomeres V about as long as I-III together.

Abdomen. – Ventrites with abundant yellowish-white pubescence not obscuring integument; apex of ventrite 5 concave centrally.

Dimensions (mm).

– Total length, 7.15;

– Prothoracic length, 1.25;

– Anterior prothoracic width, 1.30;

– Posterior and maximum prothoracic width, 1.40;

– Humeral width, 2.00;

– Elytral length, 5.15.

R. nona sp. nov. can be included in the alternative of couplet “31” from Santos-Silva et al. (2018) (modified)

31 (26). Elytra without transverse pubescent band on posterior half of elytra before apex.......................................... 31 ’ — Elytra with transverse, oblique, concave or convex pubescent band on posterior half of elytra before apex............ 32

31 ’(31). Sides of pronotum with wide longitudinal yellowish pubescent band reaching sides of prothorax; elytral apex rounded. Brazil (Espírito Santo, Rio de Janeiro, São Paulo, Santa Catarina, Rio Grande do Su. ......... R. cordigera (Aurivillius, 1920)

— Sides of pronotum with narrow longitudinal pubescent band not reaching sides of prothorax; elytral apex obliquely truncate. Ecuador.................................................................................................................. R. nona sp. nov. Etymology. – The specific epithet “nona ” (Latin, meaning ninth) is inspired by the fact that this is the ninth species of Rosalba found in Ecuador.

Remarks. – Rosalba nona sp. nov. is similar to R. alcidionoides Thomson, 1864 (see photographs on Bezark (2025) and in Santos-Silva et al. (2018)),but differs as follows: elytra about 4.0 times longer than prothorax; and humeral width about 1.45 posterior width of prothorax.In R. alcidionoides , the elytra is about 4.9 times longer than the prothorax and the humeral width is about 1.7 the posterior width of the prothorax. Additionally, the prothorax in R. alcidionoides has distinct lateral tubercles (absent in the new species) and the elytral pubescent pattern is considerably different on the posterior 2/3. According to Thomson (1864), the prosternal and mesoventral processes in Rosalba are laminiform ( R. alcidionoides was the only species included in the original description of the genus). Since we have not examined specimens of R. alcidionoide s, we do not know whether this information is correct. However, in the other species of Rosalba these processes cannot be described as laminiform, since they are considerably wide. Rosalba nona is also similar to R. digna (Melzer, 1934) (see photographs on Bezark (2025) and in Santos-Silva et al. (2018)) but differs especially by the scutellum with longitudinal pubescent band centrally (absent in R. digna ) and by the elytral pubescent pattern on the posterior 3/4 of elytra.

As well as the type species, R. nona has sparse erect setae on the elytra, especially laterally and apically, which are absent in the other Rosalba species examined by us. Therefore, the separation between Rosalba and Amphicnaeia Bates, 1866 becomes somewhat problematic, although the erect setae appear to be always more abundant in the latter.