Homonyx cupreus Guerin-Meneville 1839
Creators: name: Mondaca, José
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Rutelidae
Homonyx
Homonyx cupreus

description: Homonyx cupreus Guérin-Méneville, 1839
(Fig. 1A–J)
Homonyx cupreus Guérin-Méneville 1839:300 (original description); Burmeister 1844: 391 (catalog); Solier 1851: 94; Lacordaire 1855: 361; Reed 1876: 287 (catalog); Ohaus 1934: 71 (catalog); Blackwelder 1944: 237 (checklist); Machatschke 1970: 19 (checklist); Soula 2010: 9 (revision); Krajčík 2012: 129 (checklist); Moore et al. 2017: 119 (catalog).
Type locality: Brazil (i.e., localities within the known range of the taxon following Recommendation 76A.1.4 of the International Commission on Zoological Nomenclature 1999). The original type locality of “côtes de détroit de Magellan” (Guérin- Méneville 1839) is erroneous and is here corrected (following Recommendation 76A.2 of the International Commission on Zoological Nomenclature 1999).
Lectotype female (present designation) at NHMUK, labeled (Fig. 1B): a) “526”, b) “Magellan” [handwritten on green label], c) “ Omonyx / cupreus. guer. / Rev. Zool. (Type) / Magellan.” [handwritten on white label], d) “ Homonyx / cupreus / Guerin- Typus / Magellania” [handwritten on white label], e) “So named / in Reiches / Collection / C.W.” [typeset on white label], f) “Type” [typeset on white circle label, red margin], g) Mouthparts glued on transparent card, h) Sixth ventrite glued on cardboard, I) “ LECTOTYPE ♀ / Homonyx cupreus / Guérin-Méneville, 1839 / Det. J. Mondaca E. 2022” [typeset on red label, black margin].
New synonym. Homonyx bahianus Ohaus 1913: 495–496 [originally H. chalceus bahianus]. Type locality: San Antonio da Barra, Bahia, Brazil.
Lectotype male at ZMHB (designated by Soula 2010), labeled (Fig. 1F): a) “Typus!” [typeset on red label], b) “S Antonio da Barra / Prov. de Bahia / Ch. Pujol 1890” [typeset on beige label], c) “ Homonyx bahianus Ohs. ” [handwritten on red label], d) “ Lectotype 2010 / Homonyx / bahianus Oh / Soula det” [typeset and handwritten on red label], e) Mouthparts glued on beige cardboard, f) Male genitalia glued on beige cardboard point.
Additional material examined. Nine specimens from: BRAZIL, Bahia State: Bahia, Frey Collection, 1905-100 (1 male, NHMUK); Iaçú Fazenda Sossego, 5-XI-2013, E.F. Nascimento, J. R. Carvalho, E. Menezes, F. Bravo, D. Cordeiro (1 male, CEMT); São Félix do Coribe-Coribe, km 24, 493 m, 13°33’S, 44°15’W, 7-XII-2007, F.B., T.Z., A.N., J. R., A. (1 female, CEMT); Encruzilhada, 10-XII- 2007, 600 m, 15°28’39’’S, 40°54’57’’W, Grossi, Rafael, Parizotto (1 female, CEMT). Minas Gerais State: Águas Vermelhas, Fazenda Faceiro, xii.2012, P.C. Grossi, E.J. Grossi, G.A. R. Melo, J.A. Rafael, at light (2 females, NHMUK); Águas Vermelhas, XII-1997, F.Z. Vaz de Mello, A.M. Bello (1 male, 1 female, CEMT); Itaobim, 9-XII- 2007, 600 m, 15°28’39’’S, 40°54’57’’W, P.C. Grossi, J.A. Rafael, D. Parizotto (1 male, CEMT).
Redescription. n = 6 females, 4 males. 19.0–21.0 mm (females), 12.0–18.0 mm (males); width 9.0–10.0 mm (females), 8.0–11.0 mm (males). Color: Dorsal surface coppery red or coppery brown, shiny with metallic green reflections on head, pronotum and legs (Fig. 1A, C, H). Shape: Elongate oval, parallel-sided, diverging posteriorly towards end of body; dorsal surface convex, glabrous, venter almost flat, sparsely setose; elytral apex rounded. Head: Clypeus subtrapezoidal, rounded apically, anterior margin reflexed vertically; dorsal surface slightly convex and glabrous, densely punctate, and transversely striate; punctures small, some confluent. Frontoclypeal suture not impressed, weakly indicated laterally. Frons convex in lateral view, with small, dense punctures. Eyes small, rounded, interocular width equals 5.0 transverse eye diameters, ventrally globose; eye canthus flattened, not carinate. Mandibles exposed beyond clypeal margins, with apex bidentate and laterally with 2 large, rounded, reflexed teeth; molar area wider than long, surface strongly striate. Labrum horizontal, projected beyond clypeal margin, apex bilobed, medially emarginate and setose at margins. Maxilla strongly dentate, with 6 teeth; galea not fused, with moderately long setae; maxillary palps with 4 palpomeres; palpomere 1 shorter than 2; 2 longer than 3, 4 fusiform, longer than 2–3 together. Labium subquadrate with basal margins rounded, apex emarginate, concave in anterior half and medially sulcate posteriorly; labial palps short, with 3 palpomeres; palpomere 1 shorter than 2; 3 fusiform, longer than 1–2 together. Antenna with 10 antennomeres in both sexes, apical 3 antennomeres forming club (Fig. 1A, C); scape claviform; pedicel submoniliform; antennomere 3 subcylindrical; 4–5 subquadrate or moniliform; 6 cupiform; 6 discoidal; club with 3 antennomeres subequal or slightly longer than funicule. Pronotum: Widest at base, apical angles acute, basal angles obtuse or acute; dorsal surface glabrous, finely and densely punctate, laterally with a deep circular depression or fovea present only in females; punctures small in size; marginal bead complete, not interrupted basomedially, not setose basolaterally; posterior margin sinuate laterally and basomedially round. Scutellar shield: Subtriangular, wider than long, apex rounded; surface finely punctate, glabrous. Elytra: Together longer than broad, with dorsal surface striate and punctate, glabrous; elytral suture apically angled; humeral umbone with prominent tubercle. Venter: Punctures sparse, small to moderate. Prosternum small, subtriangular, scarcely projecting between procoxae. Mesoventrite without anterior process. Metaventrite glabrous, sparsely and finely punctate. Abdomen: Ventrite 1 short, medially subtriangular; 2–4 subequal in width; 5 wider than previous ventrites; propygidium shorter than 5 with the apex slightly emarginate in male, straight in female; surface finely, sparsely punctate, with setiferous punctures in transverse rows on posterior margins, laterally with fine transverse striae; pygidium subtriangular, wider than long; surface convex, transversally striate, setose at apex; lateral and caudal margins with complete marginal bead. Legs: Protibia with 3 external teeth unequally separated, acute distally; distal tooth elongate, externally curved, medial tooth large, basal tooth small; subapical spur variable in length, straight or slightly curved. Protarsomeres subtriangular, gradually enlarged distally. Pro-, meso-, and metatarsal onychia each with 1 seta. Meso- and metatibiae flat, with contiguous, subequal apical spurs, slightly curved and somewhat flat, with round or acute apices; apical border of mesotibia with numerous spinules, spinules also appear on external surface forming oblique carinae; metatibia without spinules at apical border, and notched. Protarsus of male with large, unequal claws; internal claw thicker, greatly recurved, simple, not toothed, apex acute or round; outer claw long, slightly curved, with apex acute; meso- and metatarsal claws similar in size, simple, not toothed. Female claws simple. Male genitalia: Aedeagus with parameres fused dorsoventrally; apices rounded and divergent externally (frontal view), curved in lateral view (Fig. 1G, J).
Remarks. Based on external morphology and color pattern of the adults, the lectotype female of H. cupreus is conspecific with the females of a species of Homonyx that inhabits eastern Brazil (Bahia and Minas Gerais states). The male genitalia of this last species is nearly identical to the male genitalia of the lectotype of H. bahianus Ohaus (= H. chalceus bahianus). Based on this evidence, I establish that H. chalceus bahianus is a new junior synonym of H. cupreus.
There appears to be only small differences in body color, size and density of the elytral punctation and shape of the parameres between H. cupreus from Brazil and H. chalceus Blanchard, 1851 from northern and central Argentina. These characters are generally highly variable between species in other Rutelini genera (e.g., Pelidnota MacLeay, 1819 and Catoclastus Solier, 1851). It is likely that H. cupreus and H. chalceus are conspecific, but this hypothesis needs to be studied further using type specimens and large series of specimens before the synonymy is made official.
Distribution. Brazil, states of Bahia and Minas Gerais (Fig. 2).
Remarks. The erroneous record from Chile was treated previously by Moore et al. (2017). Now, it is probable that the lectotype of H. cupreus comes from Rio de Janeiro (Brazil), a locality that was explored in September 1826 by Alcide d’Orbigny during his travels in South America. The state of Rio de Janeiro is next to the Brazilian state of Minas Gerais. It is possible that the distribution of H. cupreus is more extensive than currently now known and may cover territories located both in the northeast and southeast of Brazil.
description: Published as part of Mondaca, José, 2022, Lectotype designation, redescription, and synonymy of Homonyx cupreus Guérin-Méneville, 1839 (Coleoptera: Scarabaeidae: Rutelinae: Rutelini), pp. 407-412 in Zootaxa 5133 (3) on pages 408-411, DOI: 10.11646/zootaxa.5133.3.5, http://zenodo.org/record/6524014