Pseudocanthon xanthurus ( Blanchard, 1847 )

Nazaré-Silva, Everton E. & Silva, Fernando A. B., 2021, A taxonomic revision of the South American species of Pseudocanthon Bates, 1887 (Coleoptera: Scarabaeidae: Scarabaeinae: Deltochilini), Zootaxa 5027 (1), pp. 61-86 : 67-75

Pseudocanthon xanthurus ( Blanchard, 1847)

( Figs. 1E , 2B, 2F , 3B–C , 4B , 5B–C , 6B–C , 7A , 8 , 9 ) urn:lsid:zoobank.org:act:AD91B620-1E60-4091-886B-34D9D56EE278

Canthon xanthurum Blanchard, 1847: 166 (original description); Blackwelder 1944: 202 (checklist and distribution).

Canthon xanthurus: Harold 1868: 140 (checklist); Harold 1869: 995 (catalogue and distribution); Bruch 1911: 185 (catalogue and distribution); Gillet 1911: 34 (catalogue and distribution); Arrow 1913: 456 (taxonomic remarks); Schmidt 1922: 64, 82 (description and distribution); Balthasar 1939: 189–190 (description and distribution).

Canthon (Pseudocanthon) xanthurus: Krajcik 2006: 32 (checklist); Krajcik 2012: 64 (checklist).

Pseudocanthon xanthurum: Martínez 1947: 268 (catalogue, distribution, and taxonomic remarks); Halffter 1961: 232–233 (taxonomic remarks); Vaz-de-Mello 2000: 194 (checklist); Ratcliffe et al. 2015: 196 (checklist).

Pseudocanthon xanthurus: Pereira & Martínez 1956: 109 (taxonomic remarks); Martínez 1959: 57 (catalogue and distribution); Pereira & Martínez 1960: 37–38 (taxonomic remarks); Vulcano & Pereira 1964: 592 (catalogue); Vulcano & Pereira 1967: 551 (identification key); Halffter & Martínez 1977: 60 (checklist); Medina et al. 2001: 137 (checklist); Hamel-Leige et al. 2006: 14 (checklist); Medina & Pulido 2009: 59 (checklist); Carvajal et al. 2011: 119 (distribution); Schoolmeesters 2020 (catalogue); Vaz-de-Mello 2020 (checklist).

Canthon felix Arrow, 1913: 456 (original description and taxonomic remarks); Boucomont 1928: 1 (checklist); Balthasar 1939: 224 (description and distribution); Blackwelder 1944: 199 (checklist and distribution); Pereira & Martínez 1956: 109 (taxonomic remarks); Pereira & Martínez 1960: 37–38 (synonymy of Canthon felix with Pseudocanthon xanthurus ); Halffter 1961: 232–233 (cited as junior synonym of Pseudocanthon xanthurus ); Bacchus 1978: 102 (lectotype designation of C. felix ); Krajcik 2006: 32 (cited as junior synonym of Pseudocanthon xanthurus ); Ratcliffe et al. 2015: 196 (checklist).

Diagnosis. Pseudocanthon xanthurus is similar to P. perplexus in having inconspicuous microsculpture at central portion of pronotum ( Fig. 2B ). However, P. xanthurus can be distinguished from P. perplexus by the following characters: surface of clypeus, lateral edges of pronotum, humeral angle, lateral and apex of elytra with orange spots ( Fig. 3B–C ); internal edge of protibia substraight ( Fig. 2F ); apex of parameres rounded, curved outward ( Fig. 5B–C ); frontolateral peripheral (FLP) endophallite elongate, elliptical shaped ( Fig. 6B ); and accessory endophallite (AE) absent ( Fig. 6B ). In contrast, in P. perplexus dorsal surface of body almost completely black or metallic blue, orange portion restricted to clypeal surface ( Fig. 3A ); internal edge of protibia strongly arched ( Fig. 2E ); apex of parameres curved inward, with small cylindrical projection at apex of ventral edge ( Fig. 5A ); FLP elongate, bifurcate at inferior portion ( Fig. 6A ); and AE present ( Fig. 6A ).

Type material. Canthon xanthurus Blanchard lectotype ♂ (here designated; MNHN): “ 5664 ” // “TYPE” // “MUSEUM PARIS / PROVINCE DE / CORRIENTES / D’ORBIGNY 1834” // “TYPE” // “ Canthon / xanthurus / Blanch ” [unknown handwriting; Blanchard’s?] // “ LECTOTYPE ♂ / Canthon / xanthurus / Blanchard / des. E.E. Nazaré-Silva & F.A.B. Silva, 2021” . Paralectotypes: Unknown.

Canthon felix Arrow Lectotype ♂ (designated by Bacchus 1978: 102; BMNH): “ Santar / em ” // “LECTO / TYPE” // “ Limbatus / Lacordre ” // “ Canthon / felix, Arrow / type ” [Arrow’s handwriting] // “ Canthon ♂ / felix Arrow / M.E. Bacchus det 197 5 / LECTOTYPE ” . Paralectotypes ♀ ( MNHN): “ A. Fry ” // “ Pernamo. ” // “ Pseudocanthon / felix / (Arrow) / GHyAM det 76 ” [Halffter’s handwriting] // “Fry Coll. / 1905-100.” // “TYPE / co ” // “ Canthon / felix, Arrow / co-type ” [Arrow’s handwriting] // “ PARALECTOTYPE ♀ / Canthon / felix / Arrow / des. E.E. Nazaré- Silva & F.A.B. Silva, 2021” .

Non-type material examined. 277♀ and 163♂. Intraspecific patterns listed by us in morphological variation section are indicated as follows: pattern 1 or 2 for body colour; pattern A or B for male genitalia. NO DATA: 2 unsexed specimens ( CERPE; pattern 1). FRENCH GUIANA: CAYENNE: Kourou , [05°09’40.07’’S; 52°38’57.6’’W] — 1♀ ( CMNC; pattern 1); Montagne des Chevaux , [04°44’56’’N; 52°26’28’’W], 75 m, 04.II.2013 , Seag — 1♀ 1♂ ( CEMT; pattern 1); Paracou field station, [05°02’N; 52°00’W], 55 m, X.2003 , F. Feer— 3♀ 5♂ ( CEMT; pattern 1, one ♂ pattern A). SURINAME: PARAMARIBO: Zanderij , [05°53’N; 55°05’W], 17–18.IV.2010 , A. Hielkema— 1♀ ( CEMT; pattern 1). VENEZUELA: BOLÍVAR: 10 km northwest of Corocito [rainforest in Caura River], [07°32’12.27’’N; 65°00’23.23’’W], 26 m, 18.VI–03.VIII.1987 , J. Peck & S. Peck— 2♀ ( CMNC; pattern 1); 15 km northwest of Corocito , [07°32’12.27’’N; 65°00’23.23’’W], 26 m, 18.VI.1987 , J. Peck & S. Peck— 2♀ 2♂ ( CMNC; pattern 2, one ♂ pattern B); 25 km southwest of Puerto Ordaz , [08°06’21.74’’N; 62°35’49.62’’W], 260 m, 21.VI.1987 , J. Peck & S. Peck— 1♀ ( CMNC; pattern 2); 20 km east of El Palmar , [08°00’33.16’’N; 62°05’29.64’’W], 380 m, 18.VI.1996 , H. Howden & A. Howden— 1♂ ( CMNC; pattern 1); Caicara del Orinoco, 15 km east of Caicara del Orinoco , [07°35’52.63’’N; 66°00’38.47’’W], 43 m, 12.VI.1996 , H. Howden & A. Howden— 2♀ 1♂ ( CMNC; pattern 2, one ♂ pattern A); Caroní, 35 km southwest of Puerto Ordaz , [08°06’34.97’’N; 62°29’04.76’’W], 388 m, 13.VII–02.VIII.1987 , J. Peck & S. Peck— 8♀ 7♂ ( CMNC; both body colour patterns are represented, and two ♂ pattern B); Heres, 20 km southwest of Bolívar , [07°59’27.13’’N; 63°42’14.13’’W], 79 m, 19.VI.1987 , J. Peck & S. Peck— 2♀ ( CMNC; both body colour patterns are represented); Parupá , [05°41’28.21’’N; 61°34’20.64’’W], 1500 m, 27–30.VI.1987 , J. Peck & S. Peck— 1♀ ( CMNC; pattern 2); Yaracuy, Aroa , [10°00’00’’N; 68°00’00’’W], 459 m, 19.VII.2009 , pitfall with human feces, Asmussen— 1♀ ( CEMT; pattern 1). COLOMBIA: CASANARE: [05°45’32.14’’N; 72°10’20.62’’W], 184 m, I.2004 , J. Noriega— 1♀ 2♂ ( CEMT; pattern 2, one ♂ pattern B); VICHADA: Cumaribo, Santa Rita, Parque Nacional Natural El Tuparro , [05°21’03’’N; 67°52’15’’W], 135 m, 03–05.II.2004 , I. Quintero & E. González— 1♀ ( CEMT; pattern 2); VAUPÉS: Mitú, Querari Pelotão , [01°05’N; 69°51’W], 07–23.IV.1993 , C. Motta— 2♂ ( INPA; pattern 1); AMAZONAS: Leticia , [04°16’54.39’’N; 69°56’09.32’’W], 76 m, 23.II–02.III.1974 , Howden & Nealis— 2♀ ( CMNC; pattern 1). BRAZIL: No locality, 20.V.1967 , no collector—1 unsexed specimen ( DZUP, pattern 1); AMAPÁ: Porto Baton, [no coordinates], 139 m, 05.VIII.1983 , J. Lacerda— 1♂ ( DZUP; pattern 1, A); RORAIMA: Boa Vista, Serra da Moça , [02°16’13.82’’N; 60°40’28.51’’W], 105 m, VII.1997 , F. Vaz-de-Mello— 2♂ ( CEMT; pattern 1, A); Cantá, Lavrado , [02°47’N; 60°39’W], 70 m, IX.1996 , Ribeiro & Vaz-de-Mello— 1♀ 1♂ ( CEMT; pattern 1, A); RIO GRANDE DO NORTE: Natal , [05°46’45.32’’S; 35°12’03.3’’W], 31 m, V.1951 — 1♀ ( DZUP; pattern 2); Parnamarim , [05°54’41.6’’S; 35°16’16.74’’W], 56 m, IV.1950 , M.Alvarenga— 2♂ ( DZUP; pattern 2, B); CEARÁ: Maranguape, Santuário Nossa Senhora de Penha [shrubs], [03°52’29’’S; 38°40’48’’W], 96 m, 09.IV.2008 , Gillet — 1♀ 1♂ ( CEMT; ♂ with pattern 1, B and ♀ with pattern 2); Ubajara, Parque Nacional de Ubajara , [03°50’19.68’’S; 40°53’53.25’’W], 797 m, 14.II.2013 ,P.Grossi&F.Vaz-de-Mello— 1♂ ( CERPE;pattern2); Quixeramobim ,[05°29’54.23’’S; 39°19’14.25’’W], 212 m, 1926, M. Rocha — 1♀ ( MZSP; pattern 2); PIAUÍ: Canto de Buruti , [08°07’56’’S; 43°00’23’’W], 366 m, 05.IV.2008 , Gillet — 1♀ ( CEMT; pattern 2); Piracuruca, Parque Nacional de Sete Cidades , [04°06’02.71’’S; 41°42’44.63’’W], 184 m, 12.II.2013 , P. Grossi & F. Vaz-de-Mello— 1♀ ( CERPE; pattern 2); Piracuruca, Parque Nacional de Sete Cidades , [04°06’02.71’’S; 41°42’44.63’’W], 184 m, 07.III.2013 , P. Grossi & F. Vaz-de-Mello— 1♀ ( CERPE; pattern 2); Teresina , [05°02’40.87’’S; 42°45’58.44’’W], 85 m, VIII.1952 , Oliveira — 2♀ 2♂ ( DZUP; pattern 2, two ♂ pattern B); Teresina , [05°02’40.87’’S; 42°45’58.44’’W], 85 m, I.1953 , Oliveira — 3♀ ( CMNC; two ♀ pattern 2 and one ♀ pattern 1); Teresina , [05°02’40.87’’S; 42°45’58.44’’W], 85 m, I.1953 , Oliveira 4♀ 2♂ ( MZSP; two ♂ pattern 2, A, two ♀ pattern 2, and two ♀ pattern 1); MARANHÃO: Chapadinha , [04°51’50’’S; 43°20’51’’W], 17.III.2012 , C. Silva— 1♂ ( CEMT; pattern 1, B); Chapadinha, Fazenda Unha de Gato , [03°41’42.3’’S; 43°11’48.1’’W], 2016, pitfall, R. Silva & G. Machado — 1♂ ( CEMT; pattern 1, A); Itapecuru Mirim [pasture], [03°23’S; 44°32’W], 31.VIII.2010 , R. Matavelli— 3♀ 2♂ ( MZUFPA; pattern 2, two ♂ pattern B); Loreto, Pedrinhas , [06°57’18.95’’S; 45°09’27.58’’W], Mangrove, 05.X.1987 , light trap, E. Bergmann— 1♀ ( CEMT; pattern 2); Ilha de São Luís , [02°35’11’’S; 44°13’32’’W], 54 m, 04.VI.2001 , L. Costa Júnior— 1♂ ( CEMT; pattern 2); Ilha de São Luís , [02°35’11’’S; 44°13’32’’W], 54 m, 08.VI.2001 , L. Costa Júnior— 1♀ ( CEMT; pattern 1); Ilha de São Luís , [02°35’11’’S; 44°13’32’’W], 54 m, 12.VI.2001 , L. Costa Júnior— 1♀ ( MZUFPA; pattern 2); Santa Quitéria do Maranhão, Fazenda Rodiador , [03°24’50’’S; 42°40’46’’W], 47 m, 18.V.2008 , Gillet — 1♀ ( CEMT; pattern 2); Santa Quitéria do Maranhão, Fazenda Rodiador , [03°24’50’’S; 42°40’46’’W], 47 m, 23.II.2008 , Gillet — 1♀ ( CEMT; pattern 1); PARÁ: Belém, Universidade Federal Rural da Amazônia , [01°27’22’’S; 48°26’15’’W], 04–13.V.2019 , M. Silva— 7♀ 5♂ ( MZUFPA; pattern 1, one ♂ pattern A); Jacareacanga , [06°13’25.88’’S; 57°45’38.73’’W], 190 m, XII.1968 , M. Alvarenga— 2♀ ( DZUP; pattern 1); Jacareacanga , [06°13’25.88’’S; 57°45’38.73’’W], 190 m, XII.1969 , F. Barbosa— 1♀ ( DZUP; pattern 1); Monte Dourado, Jari [eucalyptus area], [00°52’04.14’’S; 52°32’05.98’’W], 28.IV.2009 , Schiffler — 3♀ ( MZUFPA; pattern 1); Monte Dourado, Jari [eucalyptus area], [00°52’04.14’’S; 52°32’05.98’’W], 01.V.2009 , Schiffler — 3♀ ( MZUFPA; pattern 1); Monte Dourado, Jari [eucalyptus area], [00°52’04.14’’S; 52°32’05.98’’W], 02.V.2009 , Schiffler — 1♀ ( MZUFPA; pattern 1); Novo Progresso, Fazenda Florentino [Amazon rainforest], [07°06’54’’S; 55°24’23’’W], 207 m, I.2011 , pitfall with human feces, Pelissari— 5♀ 3♂ ( CEMT; pattern 1, two ♂ pattern A); Paragominas , [2.9372°S; 47.2102°W], II.2011 , R. Solar— 64♀ 34♂ ( CEMT; pattern 1, five ♂ pattern A); Paragominas, Canindé Rio Gurupi , [02°34’00’’S; 46°31’00’’W], 65 m, 27.II.1966 , Malkin — 1♀ ( MZSP; pattern 1); Santarém , [02°30’15.35’’S; 54°57’16.71’’W], 23 m, VII–VIII.2003 , R. Matavelli— 3♂ ( CEMT; two ♂ pattern 2, B and one ♂ pattern 1); AMAZONAS: Benjamin Constant , [04°31’13’’S; 69°57’18’’W], III.2008 , V. Korasaki— 1♀ ( MZUFPA; pattern 2); Benjamin Constant, Comunidade Nova Aliança , [04°21’12’’S; 69°36’16’’W], 20.III.2008 , pitfall with human feces, V. Korasaki— 3♀ 2♂ ( CEMT; pattern 1, one ♂ pattern A); Benjamin Constant, Comunidade Nova Aliança , [04°22’33.57’’S; 70°01’48.59’’W], 71 m, II.2004 , P. Silva— 2♂ ( CEMT; pattern 1); Manaus, Fazenda Dimona , [02°25’S; 59°50’W], 23–26.VI.2000 , I. Quintero— 23♀ 16♂ ( INPA; pattern 1); Manaus, Fazenda Dimona , [02°25’S; 59°50’W], 05– 08.VII.2000 , I. Quintero— 14♀ 6♂ ( INPA; pattern 1); Manaus, Fazenda Esteio , [02°35’26.58’’S; 60°01’36.73’’W], 61 m, no date or collector — 1♂ ( INPA; pattern 1); Manaus, Reserva Florestal Adolpho Ducke , [02°55’56’’S; 59°58’22’’W], 28.IV–03.V.2013 , F. Vaz-de-Mello— 1♀ 2♂ ( CEMT; pattern 1, one ♂ pattern A); Nhamundá , [02°13’36.68’’S; 57°11’15.48’’W], 47 m, 1959, Capelleto — 1♂ ( DZUP; pattern 1, B); Santa Isabel do Rio Negro, Tapuruquara, Rio Negro , [00°22’47.59’’S; 64°59’46.68’’W], 45 m, 01.XII.1962 , J. Bechyne— 1♀ ( MZSP; pattern 1); São Gabriel da Cachoeira, Uapés , [00°07’05.33’’S; 67°04’19.03’’W], 69 m, 28.III.1964 , J. Bechyne & B. Bechyne— 1♂ ( CMNC; pattern 1); PARAÍBA: Coremas , [07°01’03.75’’S; 37°56’48.42’’W], 216 m, VI.1957 — 1♀ ( MZSP; pattern 2); PERNAMBUCO: Araçoiaba, Campo de Instrução Marechal Newton Cavalcanti [open habitat], [07°49’53.06’’S; 35°06’13.31’’W], 126 m, 22.I.2010 , pitfall with human feces, F. Costa— 1♀ 1♂ ( CEUPE; pattern 1, ♂ pattern A); Caruaru, Brejo Novo , [08°21’00’’S; 35°58’59.88’’W], 599 m, 18.I.2004 , pitfall with human feces, no collector— 1♂ ( CEUPE; pattern 2); Igarassu, Refúgio Ecológico Charles Darwin [Atlantic rainforest], [07°49’42.76’’S; 34°52’26.82’’W], 25.V.2007 , pitfall, M. Costa— 1♀ ( CEMT; pattern 2); Igarassu, Refúgio Ecológico Charles Darwin [Atlantic rainforest], [07°48’37’’S; 34°57’25’’W], 25.V.2007 , pitfall, Costa— 2♂ ( CEUPE; pattern 2, B); Igarassu, Refúgio Ecológico Charles Darwin [Atlantic rainforest], [07°48’37’’S; 34°57’25’’W], 10.VI.2007 , pitfall, Costa— 1♀ ( CEUPE; pattern 2); Igarassu, Refúgio Ecológico Charles Darwin [Atlantic rainforest], [07°48’37’’S; 34°57’25’’W], 31.I.2006 , pitfall with human feces, Costa— 1♀ ( CEUPE; pattern 2); Igarassu, Refúgio Ecológico Charles Darwin [Atlantic rainforest], [07°48’37’’S; 34°57’25’’W], 30.IX.2006 , pitfall with rotten meat, Costa— 1♀ 1♂ ( CEUPE; ♂ pattern 2, B and ♀ pattern 1); Igarassu, Refúgio Ecológico Charles Darwin [Atlantic rainforest], [07°48’37’’S; 34°57’25’’W], 30.III.2006 , pitfall with human feces, Silva— 1♀ ( CEUPE; pattern 1); Igarassu, Refúgio Ecológico Charles Darwin [Atlantic rainforest], [07°48’37’’S; 34°57’25’’W], 02.VI.2006 , pitfall with rotten meat, Silva— 2♀ ( CEUPE; pattern 1); Igarassu, Refúgio Ecológico Charles Darwin [Atlantic rainforest], [07°48’37’’S; 34°57’25’’W], 29.XII.2006 , pitfall with rotten meat, Silva— 1♀ ( CEUPE; pattern 2); Recife , [08°03’08.07’’S; 34°55’42.99’’W], 30 m, V.1949 , no collector— 3♀ ( MZSP; pattern 2); Recife , [08°03’08.07’’S; 34°55’42.99’’W], 30m, M.Alvarenga — 2♀ ( DZUP;pattern2); ACRE: Rio Branco ,[09°58’31.36’’S; 67°49’29.63’’W], 156 m, 29.X.1954 , M. Alvarenga— 1♂ ( MZSP; pattern 1, A); BAHIA: Cruz das Almas , [12°40’24.8’’S; 39°06’06.7’’W], I.2005 , A. Brito & G. Ribeiro— 3♀ 2♂ ( CEMT; pattern 1, one ♂ pattern A); Porto Seguro [pasture], [16°23’35’’S; 39°09’45’’W], 74 m, 15.V.2012 , L. Audino— 1♀ ( CEMT; pattern 1); Porto Seguro [pasture], [16°23’59’’S; 39°07’34’’W], 71 m, 16.V.2012 , pitfall with human feces, L. Audino— 2♀ 2♂ ( CEMT; pattern 1, one ♂ pattern A); Porto Seguro [pasture], [16°23’49’’S; 39°08’21’’W], 16.V.2012 , L. Audino— 2♀ 5♂ ( CEMT; pattern 1, one ♂ pattern A); Porto Seguro, Reserva Particular do Patrimônio Natural Estação Veracel , [16°23’15.71’’S; 39°10’11.04’’W], XI.2004 , pitfall with human feces, J. Louzada— 1♂ ( CEMT; pattern 1); MATO GROSSO: Alta Floresta , [09°54’27’’S; 56°03’18’’W], III.2008 , pitfall with human feces, E. Berenguer— 20♀ 6♂ ( CEMT; pattern 1, four ♂ pattern A); Alta Floresta , [09°54’24’’S; 56°02’39’’W], III.2008 , pitfall with human feces, E. Berenguer— 2♀ 4♂ ( CEMT; pattern 1, two ♂ pattern A); Alta Floresta , [09°51’06’’S; 55°59’04’’W], IV.2008 , pitfall with human feces, E. Berenguer— 4♀ 1♂ ( CEMT, pattern 1); Alta Floresta , [09°50’22’’S; 56°00’21’’W], IV.2008 , pitfall with human feces, E. Berenguer— 2♀ 1♂ ( CEMT; pattern 1); Alta Floresta , [09°46’55’’S; 56°02’13’’W], IV.2008 , pitfall with human feces, E. Berenguer— 1♀ ( CEMT; pattern 1); Alta Floresta , [09°51’06’’S; 55°59’04’’W], V.2008 , pitfall with human feces, E. Berenguer— 2♀ 1♂ ( CEMT; pattern 1, male pattern A); Cotriguaçu, Fazenda São Nicolau , [09°49’43’’S; 58°15’56’’W], 10.XII.2009 , F. Vaz-de-Mello— 1♂ ( CEMT; pattern 1); Cotriguaçu, Fazenda São Nicolau [fig plantation], [09°49’32’’S; 58°15’46’’W], 220 m, 10.XII.2009 , pitfall with human feces, F. Vaz-de-Mello— 1♀ ( CEMT; pattern 1); Cotriguaçu, Fazenda São Nicolau , [09°49’52’’S; 58°15’17’’W], X.2009 , pitfall, F. Vaz-de-Mello— 5♀ ( CEMT; pattern 1); Cotriguaçu, Fazenda São Nicolau , [09°51’38’’S; 58°12’53’’W], X.2009 , pitfall, F. Vaz-de-Mello— 1♂ ( CEMT; pattern 1); Cotriguaçu, Fazenda São Nicolau , [09°49’32’’S; 58°15’46’’W], 09.XI.2010 , pitfall with human feces, M. Gigliotti— 1♀ ( CEMT; pattern 1); Cuiabá, Fazenda Santhidi , [15°36’03.1’’S; 56°05’48.56’’W], 190 m, 08.I.2010 , L. Silva— 1♀ 2♂ ( CEMT; pattern 2, one ♂ pattern B); Poconé [Pantanal], [17°50.73’S; 57°24.17’W], 15.XI.2011 , pitfall with human feces, J. Silva— 2♀ ( CEMT; pattern 1); Sinop, Embrapa , [11°51’S; 55°35’W], 370 m, III–XII.2016 , pitfall, L. Lopes & R. Pita— 1♀ ( CERPE; pattern 2); Tangará da Serra, Sítio Clemente , [14°39’46’’S; 57°49’35’’W], 368 m, 12–14.XII.2012 , pitfall with human feces, R. Silva— 1♂ ( CEMT; pattern 1); RONDÔNIA: Porto Velho, Rio Madeira , [08°45’40.3’’S; 63°54’01.58’’W], 76 m, no date and collector — 1♀ ( INPA; pattern 1); MINAS GERAIS: Cordisburgo, Fazenda Pontinha , [19°07’31.09’’S; 44°19’13.63’’W], XII.1993 , F. Vaz-de-Mello— 2♀ ( CEMT; pattern 1); Cordisburgo, Fazenda Pontinha , [19°07’31.09’’S; 44°19’13.63’’W], I.1994 , F. Vaz-de-Mello— 1♀ 1♂ ( CEMT; pattern 1, ♂ pattern B); Curvelo, Fazenda do Roberto Lubernau [pasture], [18°47’43’’S; 44°38’51’’W], 561 m, 26.I.2012 , R. Macedo— 3♀ 1♂ ( CEMT; pattern 1, ♂ pattern A); Lavras , [21°14’54.56’’S; 45°00’04.95’’W], 926 m, I.1999 , J. Louzada— 1♀ ( CEMT; pattern 1); Pompéu, Fazenda do Pedro , [19°09’17’’S; 44°52’23’’W], 458 m, 22.I.2012 , pitfall with human feces, R. Macedo— 1♀ 1♂ ( CEMT; pattern 1); Visconde do Rio Branco , [21°00’49.65’’S; 42°50’15.4’’W], I.1998 , T. Cavalcanti— 2♀ ( CEMT; pattern 1); DISTRITO FEDERAL: Brasília , [15°49’36.09’’S; 47°55’18.55’’W], 1100 m, XI.1999 , at light, N. Degallier— 1♀ 1♂ ( CMNC; pattern 1, ♂ pattern A); GOIÁS: Goiatuba , [18°00’46.03’’S; 49°21’59.79’’W], 803 m, II.1947 , no collector— 1♀ ( CMNC; pattern 1); same data but, XI.1943 , no collector— 1♀ ( MZSP; pattern 1); Mineiros, Parque Nacional das Emas , [17°56’29’’S; 52°58’40’’W], 15.III.2011 , pitfall with human feces, M. Souza— 1♀ ( CEMT; pattern 1); Mineiros, Parque Nacional das Emas , [18°04’06’’S; 52°56’09’’W], 15.III.2011 , pitfall with human feces, M. Souza— 1♂ ( CEMT; pattern 2, B); Mineiros, Parque Nacional das Emas , [18°00’29’’S; 52°58’56’’W], 15.III.2011 , pitfall with human feces, M. Souza— 1♀ ( CEMT; pattern 1); RIO DE JANEIRO: Guapimirim, II.1944 , illegible collector—1 unsexed specimen ( MNRJ); Itaguaí , [22°51’47.49’’S; 43°46’40.47’’W], 26 m, I.1991 , C. Godinho— 1♀ ( CEMT; pattern 1); Rio de Janeiro , Deodoro, 20.II.1946 , W. Zikán —1 unsexed specimen ( MNRJ); Rio de Janeiro, Ilha do Governador , 16.XI.1955 , M. Alvarenga —1 unsexed specimen ( MNRJ); Rio de Janeiro , Jacarepaguá, 02.III.1952 , O. Rego —1 unsexed specimen ( MNRJ); Seropédica , Estrada Rio-São Paulo, km 47, 03.III.1948 , W. Zikán —1 unsexed specimen ( MNRJ); Seropédica, Estrada Rio-São Paulo, km 47, XII.1948 , W. Zikán —2 unsexed specimens ( MNRJ); SÃO PAULO: Bertioga, Itaguaré , [23°47’32.7’’S; 45°49’32.23’’W] — 1♀ ( CMNC; pattern 1); Bragança Paulista , [22°57’11.41’’S; 46°32’32.37’’W], 849 m, D. Vaglio — 1♀ ( MZSP; pattern 1); Intanhaém , [24°10’54.48’’S; 46°47’06.12’’W], 7 m, II.1966 , U. Martins— 1♀ ( MZSP; pattern 1); Itú, Fazenda Pau D’Alho , [23°15’50.4’’S; 47°17’58.82’’W], 601 m, 05.XI.1960 , U. Martins— 1♂ ( MZSP; pattern 1, A); MATO GROSSO DO SUL: Selvíria, Fazenda Experimental da Universidade Estadual Paulista [pasture], [20°20’51.89’’S; 51°24’51.88’’W], 03.XI.1994 ,light trap, C.Flechtmann— 1♀ ( CEMT; pattern 1); PARANÁ: Ponta Grossa , [25°05’57.93’’S; 50°09’29.96’’W], 953 m, III.1945 — 1♀ ( DZUP; pattern 1); Wenceslau Braz , [23°52’17.07’’S; 49°48’08.85’’W], 832 m, I.1941 , J. Leprevest— 1♀ ( MZSP; pattern 1); SANTA CATARINA: Anchieta , [26°34’S; 53°22’W], 08.XII.2014 , pitfall, V. Alves— 1♀ ( CEMT; pattern 1); Seara, Nova Teutonia , [27°11’S; 52°23’W], 300–500 m, 06.I.1946 , F. Plaumann— 1♀ ( CMNC; pattern 1); Seara, Nova Teutonia , [27°11’S; 52°23’W], 300–500 m, IX.1957 , F. Plaumann— 1♂ ( MZSP; pattern 1); Seara, Nova Teutonia , [27°03’00’’S; 52°24’00’’W], 864 m, XII.1971 , F. Plaumann— 2♂ ( CMNC; pattern 1, A); Seara, Nova Teutonia , [27°03’00’’S; 52°24’00’’W], 864 m, I.1975 , F. Plaumann— 1♀ ( CMNC; pattern 1). BOLIVIA: SANTA CRUZ: Buena Vista, 3,7 km southeast of Buena Vista, Hotel Flora and Fauna [transitional tropical forest], [17°29.949’S; 63°33.152’W], 405 m, 05–15.XI.2001 , M. Thomas & B. Dozier— 2♀ 2♂ ( CMNC; pattern 1, ♂ pattern A); COCHABAMBA: Chapare, S. F. Chipiriri , [16°58’07’’S; 65°23’41’’W], 400 m, XI.1959 , no collector— 1♂ ( CMNC; pattern 1, A). PARAGUAY: CORDILLERA: Piribebuy , [25°27’53.37’’S; 57°02’31.73’’W], 255 m, XI.1949 , no collector— 1♂ ( CMNC; pattern 1, A); GUAIRÁ: Villarica , [25°46’33.82’’S; 56°26’58.53’’W], 183 m, IV.1942 , no collector— 1♂ ( MZSP; pattern 1). ARGENTINA: FORMOSA: Parque Nacional Río Pilcomayo , [25°08’43.11’’S; 58°11’11.78’’W], 76 m, 17.XII.1990 , J. Peck & S. Peck— 1♀ ( CMNC; pattern 1); MISIONES: Puerto Iguazú , [25°50’53.71’’S; 54°20’48.18’’W], 294 m, X.1927 , no collector— 1♂ ( CMNC; pattern 1, A) .

Distribution. Known from Venezuela (Bolívar, Yaracuy), Suriname (Paramaribo), French Guiana (Cayenne), Colombia (Amazonas, Casanare, Vichada), Brazil (Acre, Amapá, Amazonas, Bahia, Ceará, Distrito Federal, Goiás, Maranhão, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Pará, Paraíba, Paraná, Pernambuco, Piauí, Rio de Janeiro, Rio Grande do Norte, Rondônia, Roraima, Santa Catarina, São Paulo), Bolivia (Chapare, Santa Cruz), Paraguay (Cordillera, Guairá) and Argentina (Formosa, Misiones) ( Fig. 7A ). According to literature data, this species was also cited from Peru by Ratcliffe et al. (2015). However, since the specific locality was not mentioned we have included a “?” in distribution map ( Fig. 7A ). Areas of endemism [South America]: Brazilian subregion: South Brazilian dominion: Rondônia province. Boreal Brazilian dominion: Guianan Lowlands, Imerí, Napo, Pará, and Roraima provinces. South Brazilian dominion: Yungas province. Chacoan subregion: Chacoan dominion: Caatinga, Cerrado, and Chaco provinces. Parana dominion: Atlantic and Parana provinces (see Morrone 2014: fig. 12).

Notes about the lectotype of Canthon xanthurus Blanchard, 1847 . Analyzing the original description ( Blanchard 1847), no holotype was originally fixed, and we could not find any explicit mention that C. xanthurus was described based on a single specimen. Following Recommendation 73F of the International Code of Zoological Nomenclature ( International Commission on Zoological Nomenclature 1999), it is, therefore, assumed that the type series was based on more than one individual. Fernando Vaz-de-Mello found only a single syntype of C. xanthurus in the MNHN during his studies of Scarabaeinae type specimens housed in European museums (see Vaz-de-Mello & Cupello [2018] for more details). It is possible to recognize this specimen as part of the type series because, as indicated by its labels, it was collected by Alcide d’Orbigny in Corrientes, Argentina, which is in agreement with information on the collector and type locality from the original description ( Blanchard 1847). Furthermore, the lectotype matches Blanchard’s succinct description.

Notes about the synonymy of Canthon felix Arrow, 1913 with Canthon xanthurus Blanchard, 1847 . Canthon felix was described by Arrow (1913) based on specimens from Pernambuco, Ceará (Baturité and Maranguape), Pará (Santarém), and Rio de Janeiro, in Brazil. Bacchus (1978) found eight syntypes (4 males and 4 females) in the BMNH and designated the male from Santarém as the lectotype. The paralectotypes from Para, Santarém, Pernambuco, and Baturité were found; the others (Rio de Janeiro and Maranguape) were deemed lost. Decades later, Fernando Vaz-de-Mello found two paralectotypes of C. felix , the lectotype male from Santarém, Pará (BMNH), and a paralectotype female from Pernambuco (MNHN). We examined these two specimens from photographs, as well as the lectotype of C. xanthurus from Argentina and non-type material from different localities. The lectotype and paralectotype of C. felix have orange spots on almost the entire lateral edge of the body, mainly at elytra, larger density of pronotum and elytra punctures compared to C. xanthurus . The lectotype of C. xanthurus has orange spots only at base and apex of elytra, smaller density of pronotum and elytra punctures compared to C. felix . Arrow (1913) also explicitly stated that C. felix was described based on those differences above mentioned in comparison to the type of C. xanthurus (on dorsal orange spots as well as on the pronotal and elytral punctation). However, these morphological patterns co-occur in specimens from the same locality throughout the distribution range of P. xanthurus . Also, we verified these different patterns in specimens collected near the type localities of each species name, which are least 1,600 km apart. Thus, we consider this variation as an intraspecific component, and we maintain here the synonym of C. felix with C. xanthurus proposed by Pereira & Martínez (1960).

Morphological variation. Pseudocanthon xanthurus exhibits considerable discrete intraspecific variation in body colour pattern and some structural components of male genitalia. Some specimens have orange spots on almost the entire lateral edge of the body, mainly in elytra ( Fig. 3C ). Other specimens have orange spots only at the base and apex of elytra ( Fig. 3B ). The aedeagus, in ventral view, has the apex of the parameres subparallel ( Fig. 5C ) or laterally projected ( Fig. 5B ). The frontolateral peripheral (FLP) endophallite can also present variation in width and degree of curvature. It can be narrow and straight, or wider and curved ( Fig. 6B–C ).

These patterns of variation are found throughout the range of the species, some populations being polymorphic ( Figs. 8–9 ). Regarding the body colour patterns, specimens with pattern 1 have orange spots only at base and apex of elytra ( Fig. 3B ), and have been recorded in Argentina (Formosa, Misiones), Bolivia (Chapare, Santa Cruz), Brazil (Acre, Amapá, Amazonas, Bahia, Distrito Federal, Goiás, Maranhão, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Pará, Paraná, Pernambuco, Piauí, Rio de Janeiro, Rondônia, Roraima, Santa Catarina, São Paulo), Colombia (Amazonas), French Guiana (Cayenne, Kourou), Paraguay (Cordillera, Guairá), Suriname (Paramaribo), and Venezuela (Bolívar, Yaracuy) ( Fig. 8A ). Pattern 2, in turn, includes specimens with orange spots on almost the entire lateral edge of body, mainly in elytra ( Fig. 3C ); these have been found in Brazil (Amazonas, Ceará, Goiás, Maranhão, Pará, Paraíba, Pernambuco, Piauí, Rio Grande do Norte), Colombia (Casanare, Vichada), and Venezuela (Bolívar) ( Fig. 8A ). The distribution of the two body colour patterns overlaps in several localities in Brazil (Amazonas, Goiás, Maranhão, Mato Grosso, Pará, Pernambuco, and Piauí) and Venezuela (Bolívar), being those populations polymorphic ( Fig. 8A ).

Regarding the parameres and the frontolateral peripheral endophallite, there are two general patterns. Pattern A consists of specimens having parameres apically with lateral projection ( Fig. 5B ) and narrow and straight frontolateral peripheral endophallite ( Fig. 6B ) and has been found in Argentina (Misiones), Bolivia (Chapare, Santa Cruz), Brazil (Acre, Amapá, Amazonas, Bahia, Distrito Federal, Maranhão, Mato Grosso, Minas Gerais, Pará, Pernambuco, Piauí, Roraima, Santa Catarina), French Guiana (Cayenne), Paraguay (Cordillera, Guairá), and Venezuela (Bolívar) ( Fig. 8B ). Pattern B, in turn, includes specimens having parameres apically subparallel ( Fig. 5C ) and with frontolateral peripheral endophallite wider and curved ( Fig. 6C ); these have been found in Brazil (Amazonas, Ceará, Goiás, Maranhão, Mato Grosso, Minas Gerais, Pará, Pernambuco, Piauí, Rio Grande do Norte), Colombia (Casanare), and Venezuela (Bolívar) ( Fig. 8B ). The distribution range of the two patterns also overlaps in several localities in Brazil (Amazonas, Maranhão, Mato Grosso, Minas Gerais, Pará, Pernambuco, Piauí) and Venezuela (Bolívar), being also those populations polymorphic ( Fig. 8B ) .

We have not noticied any strict association between patterns of body colour and male genital morphology. In general, specimens with orange spots only at the base and apex of elytra (pattern 1; Fig. 3B ) usually have aedeagus of pattern A ( Fig. 9 ). However, in Maranguape (Ceará), Chapadinha (Maranhão), and Cordisburgo (Minas Gerais), some specimens have genitalia of pattern B ( Fig. 9 ). Specimens with orange spots on almost the entire lateral edge of the body (pattern 2; Fig. 3C ), on the other hand, usually present aedeagus of pattern B ( Fig. 9 ). However, in Teresina (Piauí) and Caicara del Orinoco ( Venezuela), specimens have aedeagus of pattern A ( Fig. 9 ).

The P. xanthurus species concept herein recognized is a hypothesis based on the previously cited morphological and geographical evidence. Intraspecific variation in body colour patterns is common and was also recorded in many species of Deltochilini ( Silva et al. 2015; Valois et al. 2015; Silva & Valois 2019). Furthermore, the morphological variations found by us between genital patterns A and B in P. xanthurus ( Figs. 5B–C , 6B–C ) are weak if they were compared with the differences in aedeagus and endophallites between the recognized species of Pseudocanthon ( Figs. 5–6 ).

Alternatively, we are aware that each genital morph may represent a separate species lineage, both sympatric, and that each of these lineages can be polychromic. Some explanations for this pattern of shared polymorphism between sister species lineages can be the following: 1—incomplete lineage sorting, also called deep coalescence, with both descendant species inherited a polymorphism already present in the ancestral species; 2—parallelism, in which both descendant species inherited the same genetic “propensity” (in terms of genetic channelling, or biased variation) to express the character; 3—horizontal transfer (including hybridization), in which genes have somehow broken the confines of the close species lineages and moved horizontally through jumps between them ( Maddison 1997; Avise 2000). All those genetic populational mechanisms mentioned above can generate those morphological patterns observed by us. However, as the present study was only based on morphological and geographic evidence, this is not part of the scope of our work, being practically impossible to test here these scenarios and confront them with our assumption. We state that a phylogeographical approach can be useful to test our species assumption. Future studies can corroborate if the morphological variation mentioned here reflects some phylogeographic structure or resulted from ecological responses to different environmental conditions along distributional range of this supposed species. Thus, we chose to describe at this time these patterns only as an intraspecific variation of P. xanthurus .

Figures

FIGURE 1. Details of the external morphology in species of Deltochilini. A, Sylvicanthon candezei (Harold, 1869) pronotum (arrows indicate angle at lateral edge); B, Pseudocanthon chaquensis new species pronotum (arrows indicate angle at lateral edge); C, S. candezei (Harold, 1869) left elytron; D, P. chaquensis new species left elytron; E, P. xanthurus (Blanchard, 1847) hypomera (transversal carina pointed). Scale bar: 1 mm (1A, C); 0.5 mm (1B, D–E).

FIGURE 2. Details of the external morphology in species of Pseudocanthon Bates, 1887. A, P. vazdemelloi new species pronotal disc; B, P. xanthurus (Blanchard, 1847) pronotal disc; C, P. vazdemelloi new species detail of left lateral of elytron; D, P. pantanensis new species detail of left lateral of elytron (arrow indicates eighth elytral stria present); E, P. perplexus (LeConte, 1847) protibia in dorsal view (arrow indicates median emargination); F, P. xanthurus (Blanchard, 1847) protibia in dorsal view; G. P. pantanensis new species pygidium; H, P. chaquensis new species pygidium. Scale bar: 0.5 mm (2A–D); 0.2 mm (2E–H).

FIGURE 3. South American species of Pseudocanthon Bates, 1887, dorsal view. A, Pseudocanthon perplexus (LeConte, 1847); B–C, P. xanthurus (Blanchard, 1847); D, P. vazdemelloi new species; E, P. pantanensis new species; F, P. chaquensis new species. Scale bar: 1 mm (3A–E); 2 mm (3F).

FIGURE 4. South American species of Pseudocanthon Bates, 1887, ventral view. A, Pseudocanthon perplexus (LeConte, 1847); B, P. xanthurus (Blanchard, 1847); C, P. vazdemelloi new species; D, P. pantanensis new species (arrows indicate angulation at posterior edge of metafemur); E, P. chaquensis new species (arrows indicate angulation at posterior edge of metafemur). Scale bar: 1 mm (3A–E); 2 mm (3F).

FIGURE 5. Aedeagus in South American species of Pseudocanthon Bates, 1887, lateral and ventral views, respectively. A, Pseudocanthon perplexus (LeConte, 1847); B–C, P. xanthurus (Blanchard, 1847) (arrows indicate variation at apex of parameres); D. P. vazdemelloi new species; E, P. pantanensis new species; F, P. chaquensis new species. Scale bar: 0.5 mm.

FIGURE 6. Endophallites in South American species of Pseudocanthon Bates, 1887. A, Pseudocanthon perplexus (LeConte, 1847); B–C, P. xanthurus (Blanchard, 1847); D, P. vazdemelloi new species; E, P. pantanensis new species; F, P. chaquensis new species. Accessory endophallite (AE). Complex of axial and subaxial (A+SA) endophallite. Frontolateral peripheral (FLP) endophallite. Superior right peripheral (SRP) endophallite. Scale bar: 0.2 mm.

FIGURE 7. Known distribution in South America of species of Pseudocanthon Bates, 1887. A, P. perplexus (LeConte, 1847) and P. xanthurus (Blanchard, 1847); B, P. vazdemelloi new species, P. pantanensis new species, and P. chaquensis new species.

FIGURE 8. Collecting records of Pseudocanthon xanthurus (Blanchard, 1847) according to following morphological patterns. A, Pattern 1 (orange spots only at the base and apex of elytra); Pattern 2 (orange spots on almost the entire lateral edge of the body, mainly in elytra); B, Pattern A (apex of the parameres subparallel, frontolateral peripheral endophallites narrow and straight); Pattern B (apex of the parameres laterally projected, frontolateral peripheral endophallites wider and curved).

FIGURE 9. Correlation between the intraspecific morphological patterns verified in Pseudocanthon xanthurus (Blanchard, 1847). Pattern 1 (orange spots only at the base and apex of elytra); Pattern 2 (orange spots on almost the entire lateral edge of the body, mainly in elytra); Pattern A (apex of the parameres subparallel, frontolateral peripheral endophallites narrow and straight); Pattern B (apex of the parameres laterally projected, frontolateral peripheral endophallites wider and curved).