Uroxys punctatus Nazaré-Silva, Moura, & Silva, 2023

Nazaré-Silva, Everton E., Moura, Ana B. G. & Silva, Fernando A. B., 2023, A new species of Uroxys Westwood, 1842 (Coleoptera: Scarabaeidae: Scarabaeinae) from central Brazil, and taxonomical remarks on Uroxys epipleuralis (Boucomont, 1928), Zootaxa 5374 (1), pp. 106-118 : 108-111

Uroxys punctatus Nazaré-Silva, Moura, & Silva , new species

urn:lsid:zoobank.org:act:7C083026-2408-43DD-A6E5-5FBC60EA1819

( Figs. 1C–D , 2C–D, 2G–H , 3C–D, 3G , 5 )

Etymology. The name refers to the distinct ocellate punctation of the head, a diagnostic feature of the species. The name is a Latin adjective in the nominative case.

Diagnosis. Among the species of Uroxys , U. punctatus is similar to U. epipleuralis in having the clypeus with four strong, acute teeth; the elytra lacking a humeral carina and with a strong longitudinal elytral carina near stria 7; and body strongly convex, shorter than 1.3 times its maximum width. Uroxys punctatus can be distinguished by the head surface with ocellate punctures at the frontoclypeal surface ( Figs. 2C–D ) (head smooth, lacking ocellate punctures in U. epipleuralis , Figs. 2A–B ). In males, the pronotum has dense ocellate punctures evenly distributed across the surface ( Fig. 2G ) (surface of pronotum bearing irregularly distributed ocellate punctures, or dense ocellate punctures only at lateral portions in U. epipleuralis , Figs. 2E–F ). Additionally, differences were observed in the male genitalia, particularly in the medial endophallite. The cable of the inferior portion of the medial endophallite of U. punctatus is slender, and about 1.2 times longer than that of U. epipleuralis ( Figs. 3F–G ) (the inferior portion of the medial endophallite is thicker and shorter in U. epipleuralis , Fig. 3F ).

Description. Body. Length 4–5 mm. Strongly convex. Shorter than 1.3 times its maximum width, dorsal and ventral surfaces covered by small deep punctures spaced by approximately two to five times their diameter. Head. Clypeus with four acute teeth. Medial teeth larger than lateral teeth. Base of clypeal teeth bearing a single row of short setae. Clypeal teeth directed upward, in dorsal view. Suture between clypeus and paraocular areas distinct. Edge of paraocular area curved outward. Frons surface distinctly convex, without carina or groove. Clypeal surface concave. Dorsal surface of the eyes approximately twice as long as wide. Interocular width about seven times an eye width. Lateral edge of head bearing a single row of short setae on ventral surface. In ventral view, clypeal process triangular.

Thorax. Pronotum twice as wide as long. Anterior and lateral edges distinctly margined. Posterior edge bearing a row of large ocellate and elliptical punctures, approximately spaced by three to four times their diameter. Sides of pronotum with deep longitudinal sulcus extending to lateral fovea, coated by clustered ocellate punctures. Surface of pronotum, between the lateral edge and longitudinal sulcus, strongly sinuate in lateral view. Hypomera strongly convex medially. Prosternum and mesoventrite densely coated with ocellate punctures. Mesoventrite twice as wide as long. Meso-metaventral suture well impressed, tightly arcuate. Lateral lobes of metaventrite, mesepimeron, and metanepisternum densely covered by ocellate punctures. Elytra. Strongly convex medially, lacking humeral carina. Elytra bearing a strong longitudinal carina near the seventh stria. Elytral striae distinctly impressed; interstriae coated with ocellate punctures approximately as wide as the striae at anterior half of elytra, and wider than striae at posterior half of elytra. Abdomen. Surface of ventrites with a single row of ocellate punctures along anterior edge. Ventrites I–IV with about the same length at medial portion. Ventrite V twice as wide as ventrites III–IV at medial portion. Ventrite VI twice smaller than ventrite V medially. Pygidium strongly convex, twice wider than long, distinctly margined, basal sulcus absent. Legs. Protibiae with three distinct teeth at outer margin, dorsally carinate and covered by a single row of short setae. Mesotibiae and metatibiae with longitudinal row of setae at dorsal and ventral surfaces; mesotibia bearing two apical spurs and metatibia with a single apical spur. Protibial spur triangular. Profemur with trochantofemoral fovea and a longitudinal sulcus well defined at anterior portion; sulcus interrupted by anterior fovea. Tarsi apically clawed. Mesotarsomeres and metatarsomeres subtrapezoidal, bearing longitudinal row of dense setae at lateral portion. Tarsomere 5 as long as tarsomeres 3–4 combined; tarsomere 1 approximately twice as long as tarsomere 2. Male genitalia. Phallobase accounting for 2/3 of total length of the tegmen. Parameres symmetric; in lateral view, roughly triangular, slightly narrowed medially, apex rounded ( Figs. 3C–D ). In dorsal view, inner margin of parameres curved outward ( Fig. 3D ). Medial endophallite composed of superior and inferior parts ( Fig. 3E ), superior rectangular, and inferior C-shaped ( Fig. 3G ). Superior right peripheral endophallite circular, with a C-shaped cable ( Fig. 3H ). Complex of axial and subaxial endophallites elongate, Yshaped ( Fig. 3H ). Frontolateral peripheral endophallite three times shorter than axial and subaxial endophallites, roughly hook shaped ( Fig. 3H ). Sexual dimorphism. Males can be distinguished from females by the distance between medial teeth about twice the tooth width ( Fig. 2C ) (in females, distance between medial teeth of clypeus about equal to tooth width, Fig. 2D ); ocellate punctures of head densely distributed over the frontoclypeal surface, spaced approximately equal to their diameter ( Fig. 2C ) (in females, ocellate punctures evenly distributed only on frons, spaced approximately by two to three times their diameter, Fig. 2D ); surface of pronotum with denser ocellate punctures, spaced approximately equal to puncture diameter ( Fig. 2G ) (in females, pronotum with dense ocellate punctures laterally, pronotal disc with ocellate punctures spaced by approximately two to three times the puncture diameter, surface with a longitudinal strip lacking ocellate punctures, Fig. 2H ).

Type material. 3♁ 8♀ Holotype. DISTRITO FEDERAL: Brasília, Parque Nacional de Brasília [cerrado], [15°43’46’’S, 47°57’23’’W], 24.XI.2016, flight interception trap, M.V. Rocha – 1♁ ( CEMT) . Paratypes. BRAZIL: MATO GROSSO, Tangará da Serra, Paraíso farm [semideciduous forest], [14°41’44’’S, 57°24’40’’W], 500 m, 13– 15.I.2011, pitfall with human-pig dung, R.J. Silva – 1♀ ( CEMT) . MATO GROSSO DO SUL: Campo Grande , [no coordinates], 18.XII.1993, dung, W.W. Kollec – 1♀ ( CEMT) ; Campo Grande, Embrapa , [no coordinates], 13.I.1997, pitfall, W.W. Kollec – 1♀ ( CEMT) . GOIÁS: Parque Nacional das Emas , [no coordinates], 6.XII.1999, pitfall, G. Machado – 1♀ ( CEMT) . DISTRITO FEDERAL: Brasília , [no coordinates], X.1984, A. Bello – 1♀ ( CEMT) ; Brasília, Parque Nacional de Brasília [cerrado], [15°51’22’’S, 47°48’48’’W], 12.I.2016, flight interception trap, M.V. Rocha – 1♁ ( CEMT) ; Brasília, Parque Nacional de Brasília [cerrado], [15°51’22’’S, 47°48’48’’W], 7.V.2016, flight interception trap, M.V. Rocha – 1♁ ( CEMT) ; Planaltina, Estação Ecológica Águas Emendadas , [15°32’31’’S, 47°36’49’’W], 2.VIII.2006, pitfall, M.R. Frizzas – 1♀ ( CEMT) ; Planaltina, Estação Ecológica Águas Emendadas , [15°32’31’’S, 47°36’49’’W], 16–31.XII.2009, pitfall, M.R. Frizzas – 1♀ ( CEMT) . SÃO PAULO: Riolândia, Vovó Júlia farm, [19°59’46’’S, 49°38’23’’W], 31.XII.2014, pitfall, L.G. Nunes – 1♀ ( CEMT) .

Distribution. Known from Brazil (Mato Grosso, Mato Grosso do Sul, Goiás, Distrito Federal, and S„o Paulo) ( Fig. 5 ). Areas of endemism [South America]: Brazilian subregion: South Brazilian dominion: Rondônia province. Chacoan subregion: Chacoan dominion: Cerrado province. Parana dominion: Parana forest province.

Remarks. Some localities throughout the range of U. punctatus also record the presence of the close allied U. epipleuralis ( Fig. 5 ). The sympatry associated with subtle morphological differences between the species (see Diagnosis section for each species) could at first be interpreted as a case of intraspecific variation of a single species. However, the differences in the tegmen and head microsculpture are critical for diagnosing these species since they are discrete characters. Here, we follow a species concept outlined by Silva & Valois (2019), where groups of specimens with discrete morphological feature patterns suggest independent reproductive communities and, therefore, distinct evolutionary histories. Our hypothesis is based on the idea that consistently different combinations of character states in sympatry are evidence of lack of genetic recombination between groups of organisms and, therefore, for the existence of biological reproductive isolation among them. In addition, many recent papers have highlighted differences in body punctation and male genitalia patterns for species distinction in Scarabaeinae ( Génier 2012; Génier & Arnaud 2016; Cupello & Vaz-de-Mello 2018; Nunes & Vaz-de-Mello 2019; Cupello et al. 2020; Nazaré-Silva & Silva 2021; Costa-Silva et al. 2022; Valois et al. 2023). Therefore, these literature data and morphological patterns support the hypothesis that U. punctatus is a new species.

Figures

FIGURE 1. Dorsal habitus of Uroxys species. A–B, Uroxys epipleuralis (Boucomont, 1928), males; C–D, U. punctatus new species, holotype and paratype, respectively (C, male; D, female).

FIGURE 2. Head and pronotum of Uroxys species. A–B, Uroxys epipleuralis (Boucomont, 1928), head, males; C–D, U. punctatus new species head (C male; D female); E–F, U. epipleuralis (Boucomont, 1928), pronotum, males; G–H, U. punctatus new species pronotum (G, male; H, female).

FIGURE 3. The male genitalia of two species of Uroxys epipleuralis (Boucomont, 1928) and U. punctatus new species. A–B, Uroxys epipleuralis tegmen (A, lateral view; B, dorsal view); C–D, U. punctatus tegmen (C, lateral view; D, dorsal view); E, U. epipleuralis superior and inferior portions of medial endophallite, ventral view; F, U. epipleuralis inferior portion of medial endophallite; G, U. punctatus inferior portion of medial endophallite; H, U. epipleuralis superior right peripheral (SRP) endophallites, complex of axial (A), subaxial (SA), and frontolateral peripheral (FLP) endophallites.

FIGURE 5. Known distribution of Uroxys epipleuralis (Boucomont, 1928) and U. punctatus new species.