Scybalocanthon uniplagiatus ( Schmidt, 1922 ) Silva & Valois, 2019

Silva, Fernando A. B. & Valois, Marcely, 2019, A taxonomic revision of the genus Scybalocanthon Martínez, 1948 (Coleoptera Scarabaeidae: Scarabaeinae: Deltochilini), Zootaxa 4629 (3), pp. 301-341 : 337-338

Scybalocanthon uniplagiatus ( Schmidt, 1922) new combination

( Figs. 2K , 4W , 5W , 6D )

Canthon uniplagiatus Schmidt, 1922: 65 , 82, 94 (original description, remarks); Balthasar 1939: 192 (description); Pereira & Martínez 1956: 119 (synonymized Canthon uniplagiatus with Scybalocanthon pygidialis ); Krajcik 2006: 30 (catalog); Krajcik 2012: 64 (catalog); Vaz-de-Mello & Cupello 2018: 69 (figures 107–108), 70 (data of type specimens).

Canthon uniplagiatum: Blackwelder 1944: 202 (checklist).

Scybalocanthon uniplagiatus: Vulcano & Pereira 1967: 554 (distribution, identification key).

Diagnosis. Specimens of S. uniplagiatus are similar to those of S. arnaudi , S. federicoescobari , S. martinezi , S. papaxibe , and S. pinopterus by having the pronotum uniformly colored, or with one elliptical spot on the central portion ( Figs. 2K, 2A , 1P, 1I, 1D, 1T ); femora almost completely yellow or brown, with black spots only on the tips ( Fig. 3G ); eighth elytral stria with thin carina at the anterior portion ( Fig. 3D ); endophallus with bristles right beside the FLP sclerite ( Figs. 5W, R, N, H, D, Q ); and additional sclerite ( AS) absent ( Figs. 5W, R, N, H, D, Q ). They can be distinguished from those of S. arnaudi and S. pinopterus by the strongly asymmetrical parameres; left paramere with acute projection on dorsal margin and bilobate excavation on ventral margin ( Fig. 4W ) (other species with slightly asymmetrical parameres, lacking acute projection and bilobate excavation on dorsal and ventral margins, respectively ( Figs. 4S, 4E )); from those of S. federicoescobari , S. martinezi , and S. papaxibe by the bilobate excavation of the ventral margin of the left paramere extending along one-third of the paramere margin ( Fig. 4W ) (in S. federicoescobari and S. papaxibe the excavation extending along one-fourth of the paramere margin ( Figs. 4R, 4I ); in S. martinezi the excavation is wider and deeper, extending at least one-half of the paramere margin ( Fig. 4O )).

Description. Body. Oval-elongate. Surface opaque, completely microgranulate. Color. Most of pronotum, hypomera, metaepisternae, metaventrite, abdominal ventrites, pygidium, and femora yellow or light brown. Head, elytra, prosternum, mesoventrite, mesoepisternae, trochanters, and tibiae dark brown. Length. 8.5–10.3 mm. Thorax. Pronotum with one brown rounded spot at the antero-central portion ( Fig. 2K ). In some individuals, spot absent. Anterior angles of pronotum approximately 85°. Lateral margin regularly curved outward, not forming an angle at the middle portion. Elytra. Striae thin and shiny, punctures inconspicuous. Eighth stria with a thin carina at the anterior portion. Aedeagus. Parameres strongly asymmetrical ( Fig. 4W ). Dorsal margin of right paramere curved inward, apex obliquely truncate. Ventral margin of right paramere substraight, with a rounded excavation at the basal portion. Dorsal margin of left paramere curved inward from the basal to medial portions, apical portion with a short and pointed projection. Ventral margin of left paramere substraight, with a bilobate excavation at the basal portion, apical portion pointed. SRP circular, with a rounded handle-shaped extension ( Fig. 5W ). FLP short, comma-shaped, with three sets of bristles right beside it ( Fig. 5W ). A+SA with two superposed and elongate sclerites ( Fig. 5W ).

Type material. Canthon uniplagiatus Schmidt , lectotype ♂ (here designated; SMTD): “ Amazonas ” // “ Coll. C. Felsche / Kauf 20 / 1918” // “ Canthon / uniplagiatus / n. sp. a. Schmidt” // “LECTOTYPE ♂ / Canthon / uniplagiatus / Schmidt / des. F. Z. Vaz-de-Mello ”. Paralectotype ♂ ( SMTD): “ Amazonas ” // “ Coll. C. Felsche / Kauf 20 / 1918” // “ Typus ” // “ PARALECTOTYPE ♂ / Canthon / uniplagiatus / Schmidt / des. F. Z. Vaz-de-Mello ”. Paralectotype ♂ ( NHRS): “ Amazonas ” // “ uniplagiatus ” // “ uniplagia / tus A. Schm.” // “ uniplagiatus / Schm ” // “ Scybalocanthon / uniplagiatus / ( Schm ) / P. Pereira det. 60 ” // “38 / 56 ” // “3405 / E92+” // [aedeagus glued on a card] // “ PARALECTOTYPE ♂ / Canthon / uniplagiatus / Schmidt / des. F. Z. Vaz-de-Mello ” .

Non-type material [ 22 males, 18 females, 5 unsexed specimens]: BRAZIL: ACRE: Río Branco, Fazenda Catuaba , vi.1997, Morato— 1♀ ( CEMT) ; Río Branco, Fazenda Catuaba , primary forest, ii.1997, F.Z. Vaz-de-Mel- lo— 3♂ 2♀ ( CEMT) ; AMAZONAS: Br-319, Km 350 (61°50’22.6”W, 5°12’56.4”S), 2.viii.2007, H. Gasca— 1♂ 1♀ ( CEMT) ; MATO GROSSO: Cláudia (55°18’26”W, 11°26’01”S), 4.iv. 2010, 325 m, F.P. Florêncio— 1♀ ( CEMT) ; Cláudia, Fazenda Continental (55°18’24”W, 11°26’01”S), 20.ii.2011, M.F. Souza— 1♂ ( CEMT) ; Cláudia, Fazenda Continental (55°19’29”W, 11°24’38”S)— 1♀ ( CEMT) ; Cláudia, Fazenda Continental (55°17’15”W, 11°34’54”S), 20.ii.2010 — 3♂ 1♀ ( CEMT) ; Cotriguaçu, Fazenda São Nicolau (58°12’53”W, 09°50’19”S), Fungi trap, xii.2009, Vaz-de-Mello— 1♂ ( CEMT) ; Cotriguaçu, Fazenda São Nicolau , secondary forest (58°13’20”W, 9°51’18”S), 15.xii.2009, pitfall, human feces, 200 m— 2♂ 3♀ ( CEMT) ; Cotriguaçu, Fazenda São Nicolau, secondary forest ( Site 4), 230 m (9°49’55’’S, 58°13’8’’W), 2.xii.2013, F. Génier, primary forest, flight interception trap (2013- 124)— 1♂ ( CMNC) ; Cotriguaçu, Fazenda São Nicolau, secondary forest ( Site 4), 230 m (9°49’55’’S, 58°13’8’’W), 4.xii.2013, F. Génier, primary forest, dung trap (2013-136)— 1♀ ( CMNC) ; Fazenda São Nicolau ( Site 6), 220 m (9°49’16’’S, 58°15’33’’W), 1.xii.2013, F. Génier, primary forest, dung trap (2013-117)— 5♂ 3♀ ( CMNC) ; Fazenda São Nicolau ( Site 6), 220 m (9°49’16’’S, 58°15’33’’W), 3.xii.2013, F. Génier, primary forest, flight interception trap (2013-131)— 2♂ ( CMNC) ; Fazenda São Nicolau ( Site 6), 220 m (9°49’16’’S, 58°15’33’’W), 4.xii.2013, F. Génier, primary forest, flight interception trap (2013-135)— 1♂ ( CMNC) ; Curvelândia, Fazenda Aparecido, Ba- cia Cabaçal (58°00’02”W, 15°33’43”S), ii.2004, M. Santos-Filho—1 [unsexed specimen] ( CEMT) ; Indiavaí, Fazenda Nova Canaã, Bacia Jauru (58°40’06”W, 15°16’31”S), vii.2004, M. Santos-Filho—1 [unsexed specimen] ( CEMT) ; Querência, Fazenda São Luiz , ii.2009, R. Andrade—1 [unsexed specimen] ( CEMT) ; Querência, Fazenda São Luiz (52°21’77”W, 40°18’52”S), flight interception trap—1 [unsexed specimen] ( CEMT) ; Querência, Fazenda São Luiz (52°22’W, 12°39’S), vii.2008 —1 [unsexed specimen] ( CEMT) ; Juara, Usina Hidroelétrica Castanheira (57°43’5.13”W, 11°10’33.11”S), ii.2015, Río Santos— 1♀ ( CEMT) ; Tangará da Serra, Fazenda Filé do Boi (57°24’41”W, 14°38’7”S), 25.i.2011, R.J. Silva— 1♂ 2♀ ( CEMT) ; RONDÔNIA: 62 km sul de Ariquemes, Fazenda Rancho Grande, ii.1997, Vaz-de-Mello, Vulinec, & Mellow— 1♂ ( CEMT) ; PARÁ, Cachimbo (8°58’S, 54°40’W), x.1955, Werner— 1♀ ( CMNC) .

Distribution. Known from Brazil (Acre, Amazonas, Mato Grosso, Rondônia, Pará) ( Fig. 6D ). Endemism areas: Brazilian sub-region: South Brazilian dominion: Madeira and Rondônia provinces (see Morrone 2014; fig. 12).

Remarks. Schmidt (1922) described Canthon pygidialis and Canthon uniplagiatus . The author did not present a comparative diagnosis between these two species in that work. However, he made it clear that specimens of Canthon pygidialis have a dark longitudinal line on the thorax [pronotum], while Canthon uniplagiatus has a dark spot on the antero-central portion of the thorax [pronotum]. Pereira & Martínez (1956) synonymized Canthon uniplagiatus with Scybalocanthon pygidialis reporting only that they did not find differences between them. Based on type examination, we found the same differences reported above by Schmidt (1922) in describing these two species. Although we were unable to dissect any genitalia in the two type series, recently collected specimens with these respective coloration pattern on pronotum present significant differences in the shape of parameres. Specimens identified as S. uniplagiatus by us have the excavation of ventral margin of parameres deeper and wider than specimens of S. pygidialis . Besides, the dorsal margin of the left paramere has a pointed projection in specimens of S. pygidialis , while in S. uniplagiatus this projection is shorter and rounded. We therefore recognize S. uniplagiatus as a valid species. It is included in Scybalocanthon according to our current definition of the genus.

Figures

FIGURE 1. Species of Scybalocanthon, dorsal habitus. A, Scybalocanthon acrianus new species; B, S. adisi new species; C, S. aereus; D, S. arnaudi new species; E, S. batesi; F, S. chamorroi new species; G, S. cyanocephalus; H, S. darlingtoni; I, S. federicoescobari new species; J, S. haroldi new species; K, S. kaestneri; L, S. kelleri; M, S. korasakiae; N–O, S. maculatus; P, S. martinezi new species; Q–R; S. moniliatus; S. S. nigriceps; T. S. papaxibe new species. Scale bar: 2 mm.

FIGURE 2. Species of Scybalocanthon, dorsal habitus. A, Scybalocanthon pinopterus; B, S. pygidialis; C–G, S. sexpilotus; H–J, S. trimaculatus; K, S. uniplagiatus. Scale bar: 2 mm.

FIGURE 3. Details of the external morphology in Scybalocanthon. A, Elytral surface in S. chamorroi new species; B, elytral surface in S. acrianus new species; C, pygidium in S. sexpilotus; D, detail of the eighth elytral stria in S. pygidialis (carina point- ed); E, mesofemur in S. kaestneri; F, mesofemur in S. nigriceps; G, mesotarsus in S. moniliatus; H, metatarsus in S. moniliatus; I, mesotibia in S. aereus; J, mesotibia of Canthon arcabuquensis.

FIGURE 4. Aedeagus, detail of parameres in left and right view. A, Scybalocanthon acrianus new species; B, S. adisi new species; C, S. aereus; D, S. aereus (lectotype); E, S. arnaudi new species; F, S. chamorroi new species; G, S. cyanocephalus; H, S. darlingtoni; I, S. federicoescobari new species; J, S. haroldi new species; K, S. kaestneri; L, S. kelleri; M, S. korasakiae; N, S. maculatus; O, S. martinezi new species; P, S. moniliatus; Q, S. nigriceps; R, S. papaxibe new species; S, S. pinopterus; T, S. pygidialis; U, S. sexspilotus; V, S. trimaculatus; W, S. uniplagiatus. Scale bar: 0.5 mm.

FIGURE 5. Sclerites of endophallus. Superior right peripheral (SRP) sclerite. Fronto-lateral peripheral (FLP) sclerite. Complex of axial and subaxial (A+SA) sclerites.Additional sclerite (AS). Set of microbristles (Smb). Set of bristles (Sb). A, Scybalocanthon acrianus new species; B, S. adisi new species; C, S. aereus; D, S. arnaudi new species; E, S. chamorroi new species; F, S. cyanocephalus; G, S. darlingtoni; H, S. federicoescobari new species; I, S. haroldi new species; J. S. kaestneri; K, S. kelleri; L, S. korasakiae; M, S. maculatus; N, S. martinezi new species; O, S. moniliatus; P, S. nigriceps; Q, S. papaxibe new species; R, S. pinopterus; S, S. pygidialis (specimen from Amazonas, Brazil); T, S. pygidialis (specimen from Cayenne, French Guiana); U, S. sexspilotus; V, S. trimaculatus; W, S. uniplagiatus. Scale bar: 0.5 mm.

FIGURE 6. Known distribution of species of Scybalocanthon.