Scybalocanthon sexspilotus ( Guérin-Méneville, 1855 )

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: 333-335

publication ID

https://doi.org/10.11646/zootaxa.4629.3.1

publication LSID

lsid:zoobank.org:pub:1D47B452-0A40-4BC5-9BBA-C06DEB298C9A

persistent identifier

http://treatment.plazi.org/id/9D12E557-3A79-FFBC-95F1-FD21FD83C7E5

treatment provided by

Felipe

scientific name

Scybalocanthon sexspilotus ( Guérin-Méneville, 1855 )
status

 

Scybalocanthon sexspilotus ( Guérin-Méneville, 1855) 

( Figs. 1View FIGURE 1 C-G, 4U, 5T, 6B)

Canthon sexspilotum Guérin-Méneville, 1855: 587  (original description and taxonomic remarks); Blackwelder 1944: 201 (checklist).

Canthon sexspilotus: Harold 1868: 140  (catalog); Bates 1887: 28 (taxonomic remarks); Harold 1869: 992 (catalog); Gillet 1911: 33 (catalog); Schmidt 1922: 65, 80 (diagnosis); Balthasar 1939: 193 (description); Vulcano & Pereira 1964: 630 (catalog); Vulcano & Pereira 1967: 552 (distribution, identification key); Krajcik, 2006: 31 (catalog); Krajcik 2012: 64 (catalog).

Canthon rufulus Harold, 1868: 13  , 54 (identification key and description); Harold 1869: 994 (catalog; synonymized Canthon rufulus  with Canthon sexspilotus  ).

Scybalocanthon sexpilotus: Halffter & Martínez 1977: 67  (species list); Vaz-de-Mello 2000: 194 (checklist); Ratcliffe et al. 2015: 196 (cited for Peru).

Canthon imitans Harold, 1868: 13  , 56 (identification key and description); Harold 1869: 991 (catalog); Gillet 1911: 30 (catalog); Schmidt 1922: 65, 75 (diagnosis); Balthasar 1939: 193 (redescription); Blackwelder 1944: 199 (checklist); Roze 1955: 41 (checklist); Krajcik 2006: 27 (catalog); Krajcik 2012: 63 (catalog). New subjective synonymy

Scybalocanthon imitans: Pereira & Martínez 1956: 114  , 115 (catalog and identification key); Vulcano & Pereira 1964: 638 (catalog); Halffter & Martínez 1977: 67 (species list); Vaz-de-Mello 2000: 194 (checklist); Ratcliffe et al. 2015: 196 (cited for Peru).

Diagnosis. Specimens of S. sexspilotus  are readily distinguishable from all other species by the head, pronotum, femora, and pygidium bicolored, with yellow and black areas ( Figs. 2View FIGURE 2 C–G). The pronotum may have different spot patterns ( Figs. 2View FIGURE 2 C–G). In addition, males have an aedeagus with the parameres elongate, subrectangular, not excavated ventrally ( Fig. 4UView FIGURE 4); and endophallus lacking bristles or microbristles close to the FLP sclerite ( Fig. 5UView FIGURE 5).

Description. Body. Oval-elongate. Color. Body opaque, completely microgranulate. Central portion of head, most of pronotum, lateral portion of hypomera, central portion of metaventrite, abdominal ventrites, margin of pygidium, and middle of femora yellow or light brown. Margin of head, elytra, prosternum, mesoventrite, mesoepisternae, metaepisternae, lateral portion of metaventrite, coxae, trochanters, proximal and distal portions of femora, tibiae, and central portion of pygidium dark brown or black. Length. 8.0–9.0 mm. Thorax. Pronotum with six black spots (five spots at the anterocentral portion and one spot at the posterior portion) ( Fig. 2FView FIGURE 2). In some specimens, spots fused in a different way, with irregular shapes ( Figs. 2View FIGURE 2 C–E). Anterior angles of pronotum with approximately 80°. Lateral margin regularly curved outward, not forming an angle at the middle portion. Elytra. Striae thin, almost inconspicuous. Eighth stria effaced at the basal third, lacking carina at the anterior portion. Aedeagus. Parameres symmetrical, with subrectangular shape ( Fig. 4UView FIGURE 4). Dorsal margin of parameres curved inward from the basal to medial portions, apical portion substraight. Ventral margin of parameres substraight. SRP circular, with curved handle-shaped extension ( Fig. 5UView FIGURE 5). FLP I-shaped ( Fig. 5UView FIGURE 5). A+SA with two superposed and elongate sclerites ( Fig. 5UView FIGURE 5). AS I-shaped ( Fig. 5UView FIGURE 5).

Type material. Canthon sexspilotum Guérin-Méneville  , neotype ♂ (here designated; CEMT): “ BRAZIL / AM- ( Rio Solimões ) / Ilha de Marchantaria / 59°58’W, 3°15’S Várzea/ J. Adis leg. 6.I.1982 ”GoogleMaps  .

Taxonomic notes for neotype designation. According to the information provided on Methods section, specimens belonging to the type series of Canthon sexspilotum Guérin-Méneville  are considered by us to be irretrievably lost ( International Commission on Zoological Nomenclature 1999; Article 75.3.4). Hence, there is an exceptional need to clarify its identity in the context of this taxonomic revision ( International Commission on Zoological Nomenclature 1999; Article 75.3.1). Because no name-bearing type specimen is believed to be extant, and a namebearing type is necessary to fix the name of the species objectively, we herein designate neotype. So, in order to maintain the stability of nomenclature, a specimen from a locality described as the original type locality ( International Commission on Zoological Nomenclature 1999; articles 75.3.3 and 75.3.6) and corresponding to its original description (pronotum with six black spots ( Fig. 1NView FIGURE 1); see Guérin-Méneville 1855) was chosen to be the neotype ( International Commission on Zoological Nomenclature 1999; articles 75.3.2 and 75.3.5), and deposited in a recognized scientific institution that maintains a research collection with proper facilities for preserving name-bearing types ( International Commission on Zoological Nomenclature 1999; Article 75.3.7).

Non-type material [ 34 males, 43 females]: BOLIVIA: BENI: San Ramón, Estacíon San Lorenzo , disturbed gallery forest (64°26’6”W, 13°25’36”S), 13.x.2003, pitfall, human feces, 140m, A.C. Hamel & K. Walker— 2♀ ( CEMT)GoogleMaps  ; PANDO, Riberalta (11°1’S, 66°3’W), xi.1956, Fritz— 1♂ ( CMNC)GoogleMaps  ; SANTA CRUZ, CIMCA [= Centro Integral de Manejo del Comportamiento Animal?], Gral Agustín Saavedra (17°13’30’’S, 63°12’30’’W), 5.x.1984, L. Valaz— 1♂ ( CMNC);GoogleMaps  Hotel Flora y Fauna , 5 km SSE Buena Vista, 440 m (17°29.925’S, 63°39.128’W), 15- 24.xii.2003, S. & J. Peck, forest, flight interception trap (2003-131)— 1♀ ( CMNC); Provincia Ñuflo de Chaves , As- censión, xii.1953, Andrae— 1♀ ( CMNC); Provincia Ñuflo de Chaves , Ascensión, xii.1963, Andrae— 1♀ ( CMNC); Jardín Botanico Andrés Ibañez, 17–30.ix.2006, T. Vidaurre, M. Amaya, & G. Mollos— 3♂ 4♀ ( CEMT)GoogleMaps  . BRAZIL: AMAZONAS: Ilha de Marchantaria, Rio Solimões, Várzea (59°58’W, 3°15’S), 20.x.1981, J. Adis— 1♂ ( CEMT);GoogleMaps  Ega [=Tefé] (3°22’S, 64°42’W), [no date], [anonymous]— 1♂ ( CMNC);GoogleMaps  PARÁ: Colônia Rio Branco , Obidos , 2– 12.xi.1952, P.A. Telles— 1♂ ( CMNC); Mocajuba , Mangabeira (2°36’30’’S, 49°37’0’’W), xii.1952, O. Rego— 1♀ ( CMNC); Abaetetuba , 4–25.vii.1994, N. Degallier— 3♂ 7♀ ( CEMT)GoogleMaps  ; RONDÔNIA: São Francisco do Guaporé, Rebio Guaporé (63°26’W, 12°31’S), 2.x.2013, S.E. Silva— 2♀ ( CEMT)GoogleMaps  . RORAIMA: Amajari, Ilha de Maracá (61°36’424”W, 3°31’829”N), Amazon rainforest, pitfall, human feces, 10.v.2009, R. Andrade— 2♂ 1♀ ( CEMT)  . COLOMBIA: META: Mozambique, Franja de bosque de galeria, iv.1996, pitfall, human feces, 190 m, J.A. Noriega— 2♂ ( CEMT); AMAZONAS, Isla Santa Sofia , Leticia (4°2’41’’S, 70°6’5’’W), 23.ii–2.iii.1974, J. Peck— 13♂ 16♀ ( CMNC, MZUFPA);GoogleMaps  Leticia , 215 m (4°11’20’’S, 69°56’9’’W), 23.ii–2.iii.1974, [anonymous]— 1♂ 2♀ ( CMNC)GoogleMaps  . VENEZUELA: APURE: San Fernando (67°28’23’’W, 7°53’38’’N), 26.viii.2006, curso NM 2006— 1♂ 1♀ ( CEMT)GoogleMaps  . BARINAS, Santa Bárbara (7°48’30’’N, 71°10’30’’W), x.1972, Solano— 2♀ ( CMNC)GoogleMaps  . TACHIRA: Isla de Betancurt, 29.v.1986, D. Havranek— 1♀ ( CEMT)  . PERU: near Ramón Castilla, 24.ii.1972, H. & A. Howden— 3♂ 1♀ ( CMNC); near Ramón Castilla , 26.ii.1974, H. & A. Howden— 1♂ 1♀ ( CMNC)  .

Distribution. Known from Bolivia, Brazil (Amazonas, Pará, Roraima, Rondônia), Colombia, Venezuela, and Peru ( Fig. 6BView FIGURE 6). Endemism areas: Brazilian sub-region: Pacific dominion: Sabana province; Boreal Brazilian dominion: Imerí, Pantepui, and Pará provinces; South Brazilian dominion: Rondônia province (see Morrone 2014; fig. 12). As far as we know, S. sexspilotus  is the most widely distributed species of the genus. From available data, this species inhabits lowlands, gallery forests, and floodplains.

Remarks. Specimens of S. sexspilotus  from the same locality may have different spot patterns on the pronotum. The spot patterns may vary gradually from a broadly distributed black spot to only a small and restricted spot at the central portion of the anterior and posterior margins ( Figs. 2View FIGURE 2 C–G).

The holotypes of Canthon imitans Harold, 1868  and Canthon rufulus Harold, 1868  were not found by us (see Methods section). However, the possible collections in which these specimens could be found have not yet been exhaustively examined. Thus, we have decided not to designate neotypes for these nominal species at this time. According to the original description, Canthon imitans  can be characterized by the type locality ( Venezuela) and its yellow pygidium with a black central spot ( Fig. 3CView FIGURE 3) ( Harold 1868). As specimens of S. sexspilotus  are diagnosed by having a black spot on the pygidium, we are confident to establish this new synonymy. The original description is not sufficient to establish the identity of Canthon rufulus  . Thus, this situation is a typical example of a “species inquirenda”. However, because the nominal species was synonymized with Canthon sexspilotum Guérin-Méneville, 1855  by its own author ( Harold 1869), we prefer to maintain here the synonymy previously proposed in order to maintain the stability of the nomenclature.

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Coleoptera

Family

Scarabaeidae

Genus

Scybalocanthon

Loc

Scybalocanthon sexspilotus ( Guérin-Méneville, 1855 )

Silva, Fernando A. B. & Valois, Marcely 2019
2019
Loc

Canthon sexspilotum Guérin-Méneville, 1855: 587

Blackwelder, R. 1944: 201
Guerin-Meneville, F. E. 1855: 587
Loc

Canthon sexspilotus: Harold 1868: 140

Krajcik, M. 2012: 64
Krajcik, M. 2006: 31
Vulcano, M. A. & Pereira, F. S. 1967: 552
Vulcano, M. A. & Pereira, F. S. 1964: 630
Balthasar, V. 1939: 193
Schmidt, A. 1922: 65
Gillet, J. J. E. 1911: 33
Bates, H. W. 1887: 28
Harold, E. von 1869: 992
Harold, E. von 1868: 140
Loc

Canthon rufulus

Harold, E. von 1869: 994
Harold, E. von 1868: 13
Loc

Scybalocanthon sexpilotus: Halffter & Martínez 1977: 67

Ratcliffe, B. C. & Jameson, M. L. & Figueroa, L. & Cave, R. D. & Paulsen, M. J. & Cano, E. B. & Beza-Beza, C. & Jimenez-Ferbans, L. & Reyes-Castillo, P. 2015: 196
Vaz-de-Mello, F. Z. 2000: 194
Halffter, G. & Martinez, A. 1977: 67
Loc

Canthon imitans

Krajcik, M. 2012: 63
Krajcik, M. 2006: 27
Roze, J. A. 1955: 41
Blackwelder, R. 1944: 199
Balthasar, V. 1939: 193
Schmidt, A. 1922: 65
Gillet, J. J. E. 1911: 30
Harold, E. von 1869: 991
Harold, E. von 1868: 13
Loc

Scybalocanthon imitans: Pereira & Martínez 1956: 114

Ratcliffe, B. C. & Jameson, M. L. & Figueroa, L. & Cave, R. D. & Paulsen, M. J. & Cano, E. B. & Beza-Beza, C. & Jimenez-Ferbans, L. & Reyes-Castillo, P. 2015: 196
Vaz-de-Mello, F. Z. 2000: 194
Halffter, G. & Martinez, A. 1977: 67
Vulcano, M. A. & Pereira, F. S. 1964: 638
Pereira, F. S. & Martinez, A. 1956: 114