Scybalocanthon trimaculatus ( Schmidt, 1922 )

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 : 335-337

Scybalocanthon trimaculatus ( Schmidt, 1922)

( Figs. 2 H–J, 4V, 5U, 6C)

Canthon trimaculatus Schmidt, 1922: 65 , 94 (original description); Balthasar 1939: 191 (identification key); Vulcano & Pereira 1967: 552 (distribution, identification key); Krajcik 2006: 31 (catalog); Krajcik 2012: 64; Vaz-de-Mello & Cupello 2018: 69 (figures 105–106), 70 (data of type specimens).

Canthon trimaculatum: Blackwelder 1944: 202 (checklist).

Scybalocanthon trimaculatus: Vulcano & Pereira 1967: 554 (distribution, identification key); Halffter & Martínez 1977: 6 (checklist); Medina et al. 2001: 137 (cited for Colombia); Medina et al. 2003: 65 (distribution); Carvajal et al. 2011: 316 (cited for Ecuador); Ratcliffe et al. 2015: 195 (cited for Peru); Chamorro et al. 2018: 98 (cited for Ecuador); Vaz-de-Mello & Cupello 2018: 69 (figures 105–106), 70 (data of type specimens); Chamorro et al. 2019: 232 , 233 (catalog of dung beetles species from Ecuador).

Diagnosis. Specimens of S. trimaculatus are readily distinguishable from all other species by the body with metallic sheen, femora bicolored, pronotum with three black spots (two rounded spots on each side of midline anteriorly and one quadrate spot on midline posteriorly). In some individuals, anterior spots are missing, in others spots are fused and two smaller additional spots are present laterally ( Figs. 2 H–J); eighth elytral stria lacking carina at the anterior portion; and endophallus with microbristles right beside the FLP sclerite ( Fig. 5V ).

Description. Body. Oval-elongate, with variable metallic sheen. Color. Most of pronotum, lateral portion of hypomera, pygidium, and middle of femora yellow or light brown. Head, elytra, prosternum, mesoventrite, mesoepisternae, metaepisternae, metaventrite, abdominal ventrites, trochanters, proximal and distal portions of femora, and tibiae dark brown or black. Length. 7.0–10.0 mm. Thorax. Pronotum with three black spots (two rounded spots on each side of midline anteriorly and one quadrate spot on midline posteriorly). In some individuals, anterior spots are missing, in others spots are fused and two smaller additional spots are present laterally ( Figs. 2 H–J). Anterior angles of pronotum approximately 85°. Lateral margin regularly curved outward, not forming an angle at the middle portion. Elytra. Striae thin, shiny, impressed, punctures inconspicuous. Eighth stria effaced at the basal third, lacking carina at the anterior portion. Aedeagus. Parameres symmetrical, apex pointed ( Fig. 4V ). Dorsal margin of parameres curved inward at the basal portion. Ventral margin of parameres curved inward at the basal and apical portions, medial portion curved outward. SRP circular, with rounded handle-shaped extension ( Fig. 5V ). FLP “J”- shaped, with microbristles right beside it ( Fig. 5M ). A+SA with two superposed and elongate sclerites ( Fig. 5V ). AS subrectangular ( Fig. 5V ).

Type material. Canthon trimaculatus Schmidt , lectotype ♂ (here designated; SMTD) : “Cachabé / low C. I. 97. / (Rosenberg)” // “ Coll. C. Felsche / Kauf 20 / 1918” // “ Canthon / trimaculatus / n.sp. a. Schmidt ” // “Typus” // “ LECTOTYPE ♂ / Canthon / trimaculatus / Schmidt / des. F. Z. Vaz-de-Mello. ” Paralectotypes 1 ♂ and 2♀ ( SMTD) : “R. Dagua / Colombia / W. Rosenberg” // “ Coll. C. Felsche / Kauf 20 / 1918” // “ PARALECTOTYPE ♂ or ♀ / Canthon / trimaculatus / Schmidt / des. F. Z. Vaz-de-Mello ”. Paralectotype ♂ ( SMTD) : “Cachabé / to Paramba / II. 97” // “ Coll. C. Felsche / Kauf 20 / 1918” // “ PARALECTOTYPE ♂ / Canthon / trimaculatus / Schmidt / des. F. Z. Vaz-de-Mello ”. Paralectotype ♀ ( SMTD) : “Cachabé / low c. XII. 96 / (Rosenberg)” // “ Coll. C. Felsche / Kauf 20 / 1918” // “ PARALECTOTYPE ♀ / Canthon / trimaculatus / Schmidt / des. F. Z. Vaz-de-Mello ”. Paralectotype ♀ ( SMTD) : “ Surinam ” // “ Coll. C. Felsche / Kauf 20 / 1918” // “ PARALECTOTYPE ♀ / Canthon / trimaculatus / Schmidt / des. F. Z. Vaz-de-Mello ”. Paralectotype ( IRSN): “ Columbie ” // trimaculatus / m. ” // “ J.J. Gillet det. / vend.: / Canthon / trimaculatus Gillet / R.M.H.N. Belg. 10.640” // “ PARALECTOTYPE ♀? / Canthon / trimaculatus / Schmidt / des. F. Z. Vaz-de-Mello ” . Paralectotype ♀ ( NHRS) : “ R. Dagua / Colombia / W. Rosenberg ” // “ trimacul. ” // “trimaculatus / Schm ” // “ Scybalocanthon / 3- maculatus / (Schm) / P. Pereira det. 60 ” // “37 / 56” // “ PARALECTOTYPE ♀ / Canthon / trimaculatus / Schmidt / des. F. Z. Vaz-de-Mello ” .

Non-type material [ 100 males, 114 females]: COLOMBIA: CHOCÓ: Unión Panamericana, Salero (76°44’W, 5°32’N), 3–5.vi. 2010, 120 m, J. Arias— 3♂ 1♀ ( CEMT) ; Quibdó-Istmina km 40 (5°22’N, 76°37’W), ix.1972, Mar- tínez— 1♂ ( CMNC) ; Quibdó , La Troja, ix.1972, Martínez— 1♂ 1♀ ( CMNC) ; VALLE DEL CAUCA, Anchicaya Dam , 70 km E Buenaventura, 366 m (3°46’N, 76°43’W), 26.vii.1970, H. &A. Howden, human feces— 1♀ ( CMNC) ; NARIÑO: Barbacoas, Vereda El Peje, Llanura Pacifica , interior de bosque (78°45’9.88”W, 1°25’59.88”N), pit- fall, human feces, 5–15.xii. 2009, 715 m, J. Castillo-Garcia & P. Botina-Beltrán— 1♂ ( CEMT) ; Altaquer, El Barro, Reserva Natural Rio Ñambi , flanco occidental de la cordillera occidental (78°5’W, 1°18’N), 2–15.v.2010, pitfall, human feces, 1450 m— 1♂ ( CEMT) ; La Espriella , iv.1995, 50 m, F. Escobar— 2♂ ( CEMT) . ECUADOR: CANÃR: Javín , ii.1992, 850– 1400 m, P. Arnaud— 1♂ ( CEMT) ; CARCHI: Cabeceras Río Baboso—8 [unsexed specimens] ( MQCAZ) ; Tobar Donoso 300 m—5 [unsexed specimens] ( MECN) ; COTOPAXI: Guasaganda Km 4, 20.xii. 1997, 500 m, C. Carpio— 1♂ 1♀ ( CEMT) ; IMBABURA: Lita 682 m—5 [unsexed specimens] ( MQCAZ) . SANTO DOMINGO DE LOS TSACHILAS: La Perla—5 [unsexed specimens] ( MQCAZ) ; TUNGURAHUA: Banõs , xi.1979, [anonymous]— 1♂ ( CEMT) . ESMERALDAS, Charco Vicente (0°42’4’’N, 78°54’38’’W), 16.v.2001, J. Quito & F. Añapa, pitfall trap, human feces— 3♂ 2♀ ( CMNC) ; Chispero (0°47’N, 78°55’W), 15.ii.2001, J. Celi & I. Yépez, pitfall trap, human feces— 14♂ 15♀ ( CMNC) ; Estación Biológica Bilsa (0°20’24’’N, 79°42’36’’W), 5.vi–7.vii.1996, P. Hibbs, flight interception trap— 1♂ ( CMNC) ; Estación Forestal La Chiquita , 11 km SE San Lorenzo, 5 m (1°10’N, 78°47’W), 6–11.vi.1975, S. Peck, forest, dung traps— 9♂ 12♀ ( CMNC, MZUFPA) ; Majua (0°42’11’’N, 79°32’27’’W), 28.iii.2001, J. Celi & I. Yépez, pitfall trap, human feces— 1♂ 1♀ ( CMNC) ; Palma Real (0°22’48’’N, 79°20’29’’W), 24.iii.2001, I. Yépez, pitfall trap, human feces— 17♂ 13♀ ( CMNC) ; Palma Real (0°22’48’’N, 79°20’29’’W), 25.iii.2001, J. Celi, pitfall trap, human feces— 3♂ 5♀ ( CMNC) ; Playa de Oro, Esteiro Pote (0°51.875’N, 78°43.743’W), 12.ii.1999, J. Celi & A. Dávalos, pitfall trap, feces— 1♂ ( CMNC) ; Playa de Oro, Esteiro Pote (0°51.875’N, 78°43.743’W), 11.xii. 1998, 200 m, A. Dávalos— 1♂ 1♀ ( CEMT) ; Playa de Oro, Esteiro Pote (78°43.743’W, 00°51.875’N), 12.ii.1999, J. Celi & A. Dávalos— 2♂ 5♀ ( CEMT) ; Playa de Oro, Estación La Chiquita (78°45’48.1”W, 1°14’1.3”N), 4.v.1997, 60 m, C. Castro— 1♂ ( CEMT) ; Playa Rica (0°53’N, 78°46’W), 21.iii.2001, J. Celi, pitfall trap, human feces— 5♂ 9♀ ( CMNC) ; Playa Rica (0°53’N, 78°46’W), 22.iii.2001, I. Yépez, pitfall trap, human feces— 7♂ 6♀ ( CMNC) ; Punta de Venado (0°56’38’’N, 78°59’46’’W), 23.xi.2000, J. Celi, pitfall trap, human feces— 1♂ ( CMNC) ; San Mateo (0°53’15’’N, 79°38’5’’W), 5.x.1956, Förster— 1♂ ( CMNC) ; Tsejpi (0°47’N, 78°50’W), 17.ii.2001, I. Yépez, pitfall trap, human feces— 4♂ 2♀ ( CMNC) ; Tsejpi (0°47’N, 78°50’W), 18.ii.2001, I. Yépez, pitfall trap, human feces— 1♂ 2♀ ( CMNC) ; Tsejpi (0°47’N, 78°50’W), 19.ii.2001, J. Celi, pitfall trap, human feces— 2♂ 5♀ ( CMNC) . LOS RÍOS, 47 km S Santo Domingo , 213 m (0°35’S, 79°22’W), 24.ii.1976, H.F. Howden & V.G. Nealis— 2♂ 1♀ ( CMNC) ; 47 km S Santo Domingo , 213 m (0°35’S, 79°22’W), 27.ii.1976, V. Nealis— 1♂ ( CMNC) ; Estación Científica Río Palenque [site 2], 200 m (0°36’S, 79°21’W), 25.iv– 6.vi.1996, P. Hibbs, flight interception trap (1996-02)— 1♂ ( CMNC) ; Estación Científica Río Palenque [site 2], 200 m (0°36’S, 79°21’W), iii.1989, P.L. Arnaud— 3♂ ( CEMT) ; Estación Científica Río Palenque , 47 km S Santo Do- mingo [site 1], 250 m (0°37’48’’S, 79°24’26’’W), 28–31.vii.1976, S. Peck, forest— 1♂ ( CMNC) ; Estación Científica Río Palenque , 47 km S Santo Domingo [site 1], 250 m (0°37’48’’S, 79°24’26’’W), 16–27.ii.1979, S.A. Marshall, dung trap— 2♂ ( CMNC) ; Estación Científica Río Palenque , 47 km S Santo Domingo [site 1], 250 m (0°37’48’’S, 79°24’26’’W), 17–25.ii.1979, L. Ling— 5♂ 8♀ ( CMNC) ; Estación Científica Río Palenque , 47 km S Santo Do- mingo [site 1], 250 m (0°37’48’’S, 79°24’26’’W), 19–20.ii.1979, L. Ling, dung cup trap— 1♀ ( CMNC) ; Estación Científica Río Palenque , 47 km S Santo Domingo [site 1], 250 m (0°37’48’’S, 79°24’26’’W), 21–22.ii.1979, L. Ling, dung cup trap— 2♂ 3♀ ( CMNC) ; Estación Científica Río Palenque , 47 km S Santo Domingo [site 1], 250 m (0°37’48’’S, 79°24’26’’W), 5.v–25.vii.1985, S. & J. Peck, malaise/flight interception trap— 1♂ 1♀ ( CMNC) ; Es- tación Experimental Tropical Pichilingue, Quevedo (1°0’13’’S, 79°27’50’’W), viii.1972, Martínez— 1♀ ( CMNC) ; Estación Experimental Tropical Pichilingue, Quevedo (1°0’13’’S, 79°27’50’’W), ix.1972, Martínez— 1♀ ( CMNC) ; Estación Experimental Tropical Pichilingue, Quevedo (1°0’13’’S, 79°27’50’’W), v.1976, Martínez— 7♀ ( CMNC) ; Estación Experimental Tropical Pichilingue, Quevedo (1°0’13’’S, 79°27’50’’W), xi.1976, Paliz— 1♀ ( CMNC) ; Estación Experimental Tropical Pichilingue, Quevedo (1°0’13’’S, 79°27’50’’W), i.1977, Paliz— 1♀ ( CMNC) ; Río Palenque (0°37’48’’S, 79°24’26’’W), 24.ii.1979, S. Marshall— 1♀ ( CMNC) ; MANABÍ, 78 km NE Chone, 85 km WSW Santo Domingo , 450 m (0°20’46’’S, 79°42’20’’W), 9–12.vi.1976, S. Peck, forest, dung traps— 2♀ ( CMNC) ; 90 km WSW Santo Domingo, 73 km NE Chone , 300 m (0°20’52’’S, 79°44’22’’W), 6–9.vi.1976, S. Peck, forest, dung trap (dung traps 3–5)— 3♂ 2♀ ( CMNC) ; PICHINCHA, 4 km SE Santo Domingo , 500 m (0°16’S, 79°7’W), 8–22.vi.1975, S. Peck, forest, dung trap— 2♂ 1♀ ( CMNC) ; Llurimaguas “Guayabilla”, R. Guayllabamba, xii.2010, W. Chamorro & P. Lahuatte— 1♂ ( CEMT) ; Chiriboga road Km 12–20, 1–6.iii.1987, 1200–1600 m, P.L. Arnaud— 1♀ ( CEMT) .

Distribution. Known from Colombia and Ecuador ( Fig. 6C ). Endemism areas: Brazilian sub-region: Pacific dominion: Chocó-Darién, Western Ecuador, and Cauca provinces (see Morrone 2014; fig. 12).

Remarks. Molano & Medina (2010) presented a different interpretation relative to the identity of the FPL sclerite in this species. The authors described and illustrated this sclerite only as membranous (see fig. 95 in Molano & Medina 2010). In fact, a membranous portion with microbristles exists where this sclerite is located ( Fig. 5V ). However, according to our interpretation of the primary homology of the sclerites in Scybalocanthon , the FLP sclerite would be one of the two sclerites described and illustrated as lateral sclerites by the authors (see fig. 106 in Molano & Medina 2010). Thus, the specimens examined by us had only one lateral sclerite (referred to here as additional sclerite ( AS) according to the nomenclature proposed by Tarasov and Génier 2015).

Figures

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 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.