Dichotomius (Luederwaldtinia) irinus Harold 1867
Creators: name: Valois, Marcely C.
name: Vaz-De-Mello, Fernando Z.
name: Silva, Fernando A. B.
Publisher: name: Zenodo
Year: 2017
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Scarabaeidae
Dichotomius
Dichotomius irinus

description: Dichotomius (Luederwaldtinia) irinus (Harold, 1867)
(Figs 3 a–h, 10b, 11f, 12b)
Pinotus irinus Harold, 1867: 97; Felsche, 1901a: 140 (identification key); Luederwaldt, 1929: 82 (identification key and diagnosis); Blackwelder, 1944: 207 (checklist).
Dichotomius irinus: Vaz-de-Mello, 2000: 193 (checklist).
Material examined. Type material, Pinotus irinus Harold, Lectotype ♂ (here designated; MNHN). 1. [old white label, bordered in red, Harold's handwritten] Nov. Frib. Columb. P. irinus Harold / 2. [white label, bordered in black, printed in black] Ex — Musaeo, E. Harold/ 3. [green label, small] Museum Paris, ex Coll., R. Oberthur/ 4. [red label, bordered and printed in black, handwritten] Lectotype ♂, Pinotus irinus Har., des. F. Z. Vaz-de-Mello, 2014.
Non-type material [278 males and 295 females]. BRAZIL: BAHIA: Cruz das Almas, [39°06'18.8"W; 12°39'57.1"S], I.2005, Ribeiro Junior & G. R. Brito — 4♂ 5♀ (CEMT), Embrapa [Empresa Brasileira de Pesquisa Agropecuária], III.1999, O. Meira — 1♂ 2♀ (CEMT); Porto Seguro, [16°25'46.2"S 39°03'55.5"W], VII.1992, E. Grossi — 1♂ 1♀ (CEMT), same data but VII.1990, E. Grossi — 1♂ (CEMT); Caetité, [42°29'27.5"W; 14°04'05.5"S], C. Uran. Lagoa Real — INB, I.2000, Nessimian & Baptista — 1♀ (CEMT); Boa Vista do Tupim [40°36'16.2"W; 12°39'37.6"S], Fazenda morro de pedra, III.2010, Ulisséa — 8♂ 9♀ (CEMT); Milagres, Caatinga Arbórea, [12°54,537' S, 39°51,272' W], 7.I.2011, Medina, A. Campos, M. & Ulysséa, M. — 1♀ (CEMT); Lençóis, [12°34'09.4"S, 41°23'27.6"W], Marimbos, 13.X.2003, P.P. Lopes — 1♂ (CEMT); Feira de Santana, [12°15'28.0"S, 38°57'58.4"W], VI.1995, P.P. Lopes — 1♀ (CEMT); Senhor do Bonfim, Serra Maravilha, (10°23,950'S, 40°12,495'W), 8.X.2005, P.P. Lopes — 1♂ (CEMT); ESPÍRITO SANTO: Anchieta, (40°35'36"W; 20°46'10"S), XII.2010, M.F. Souza — 20♂ 13♀ (CEMT); Cachoeira do Itapemirim, [20°46'36.0"S, 41°09'34.9"W], I.1998, J. Louzada — 4♂ 3♀ (CEMT), same data but Usina Paineiras, I.2007, J. Louzada — 8♂ 11♀ (CEMT), same data but VIII.1994, J. Louzada — 1♂ 1♀ (CEMT), same data but I.1995, J. Louzada — 15♂ 18♀ (CEMT), same data but VIII.1994, J. Louzada — 19♂ 9♀ (CEMT); Linhares, Parque Nacional Sooretama, [39°56'42.1"W; 19°25'09.6"S], X.1962, Martínez — 2♂ 2♀ (CMN); same data but Reserva Florestal Vale do Rio Doce, IX.1996, J. S. Santos — 31♂ 22♀ (CEMT), same data but VII.1996, J. S. Santos — 32♂ 57♀ (CEMT), same data but IX.2012, R. C. Lima — 3♂ 5♀ (CEMT), same data butFazenda Santa Terezinha, Caliman Agrícola S /A, X.2002, P.C. Grossi — 1♂ 3♀ (CEMT), same data but Fazenda Lagoa do Macuco, [38°39'43"W; 19°03'50"S], I.2000, F. Genier & S. Ide — 13♂ 12♀ (CMN); Marataízes, [40°50'29.3"W; 21°02'25.2"S], I.2007, L. Vieira — 6♂ 12♀ (CEMT); Presidente Kennedy, [41°02'49.9"W; 21°05'48.6"S], Praia de Marobá, II.1993, E. Grossi — 2♂ 6♀ (CEMT), same data but I.2007, J. Louzada — 24♂ 29♀ (CEMT); Regência, [39°53'05"W; 19°39'57"S], I.2007, L. Vieira — 18♂ 12♀ (CEMT); Venda Nova do Imigrante, [40°22'12.4"W; 20°26'18.8"S], II.1989, E. J. Grossi — 1♂ (CEMT); Vila velha, Barra do Jacú, [40°22'12.4"W; 20°26'18.8"S], VIII.2004, Schiffler — 5♂ 4♀ (CEMT); Vitória, Parque Estadual da Fonte Grande, [40°19'55.0"W; 20°17'57.8"S], IX.2004, Bravim, Parnagnani & Schiffler — 2♂ 3♀ (CEMT); Venda Nova, XI.1991, E. Grossi — 1♂ 1♀ (CEMT). MINAS GERAIS: Açucena, [42°32'33.6"W; 19°03'57.6"S], II.1957, A. Machado — 1♂ (CEMT); Águas Vermelhas, [41°27'12.9"W; 15°44'11.8"S], XII.1997, Vaz-de-Mello & Bello — 20♂ 17♀ (CEMT); same data but XII.1998, F. Vaz-de-Mello — 2♂ 2♀ (CEMT); XII.1997 — 2 ♂ (CEMT); Diamantina, Campus UFVJM, [Universidade Federal dos Vales do Jequitinhonha e Mucuri], [43°36'28.5"W; 18°14'32.6"S], I.2005, S. Lassis Jr. — 17♂ 13♀ (CEMT); Ipatinga, [42°36'36.7"W; 19°24'57.9"S], XI.1991, E. Grossi — 1♂ 4♀ (CEMT), same data but XI.1992 — 4 ♂ 7♀ (CEMT), same data XII.1992 — 1 ♂ (CEMT); Marliéria, [42°44'12.1"W; 19°42'33.4"S], VII.1992, F. Vaz-de-Mello — 2♀ (CEMT). RIO DE JANEIRO: Cabo Frio, [41°57'06.7"W; 22°48'11.2"S], I.1991, E. Grossi — 1♂ 1♀ (CEMT); Guapimirim, [close to Guapim-açu river], (42°53'20"W; 22°34.96'S), IV.2013, T. Carvalho & Muzêda — 2♀ (CEMT); Jardim Botânico, [43°13'30.1"W; 22°58'02.3"S], II. 1992, F. Vaz-de-Mello — 1♂ 2♀ (CEMT), same data but II.1991 — 1 ♂ (CEMT); Parque Lage, II.1992, F. Zagury — 3♂ 3♀ (CEMT), same data but II.1991 — 1 ♀ (CEMT); Floresta da Tijuca, [43°17’10.3”W; 22°56’46”S], II.2009, W. Beiroz- 1♂ (CEMT).
Diagnosis. Dichotomius irinus are similar to D. schiffleri in having the disc of the pronotum and pygidium with ocellate punctures (Figs 3 d, 11g). However, it can be distinguished by: pronotum convex in lateral view (as in Fig. 11 a); clypeofrontal suture with conical horn (Figs 3 b–c); male clypeal surface almost smooth, with weaklydefined transversal ridges on the anterior portion (Fig. 3 b).
Redescription. Length: 12–16 mm. Body black with weak bluish sheen (Fig. 3 a). Head: male genal surface with ocellate punctures separated from each other by approximately half their diameter (Fig. 3 b). Dorsal interocular surface with slight depression on its central portion; surface covered by ocellate punctures, denser near to the eyes; punctures spaced by less their diameter (Fig. 3 b). Pronotum: convex in lateral view. Disc with ocellate punctures spaced by approximately twice their diameter (Fig. 3 d). Anterior margin with row of large punctures, absent only medially. Posterior margin with row of large ocellate punctures. Margination of posterior border with large and dense punctures near posterior angles. Hypomera: posterolateral portion with dense elliptical and setigerous punctures spaced by less than their diameter, some punctures touching. Metasternum: disc smooth; anterior lobe with setigerous punctures, larger with long setae near inner margin of mesocoxae. Elytra: surface of interstriae shiny and punctate, punctures noticeable at high magnification (Fig. 5 e). Elytral striae deeply impressed (Fig. 5 e). Legs: ventral surface of profemur with large ocellate and setigerous punctures, usually denser near the apical half. Anterior and posterior margin of profemur finely sulcated; sulcus surface with well-defined microsculpture. Posterior margin of meso and metafemur with longitudinal sulcus; sulcus approximately one-fifth as wide as the femur (Fig. 11 d). Ventral surface of mesofemur with setigerous punctures on apical half. Ventral surface of mesotibia with row of setae toward the body restricted to the apical third of the mesotibia (Fig. 11 f, arrow). Abdomen: medial portion of sternites shiny or with a single row of punctures on anterior margin; lateral portion with rounded and dense ocellate punctures on anterior half. Male medial portion of sixth sternite as long as half of the fifth. Pygidium: slightly wider than long. Aedeagus: parameres subtriangular, 2/3 as long as the phallobase. (Figs 3 f–h). [lateral view] — dorsal margin of parameres strongly curved outward on apical half (Fig. 3 f). Ventral margin of parameres slightly curved inward on basal-third and apical two-thirds; curves separated by a convex portion (Fig. 3 f). [ventral view] — inner margins of parameres slightly curved outward (Fig. 3 g). [dorsal view] — basal portion of parameres wider than apical portion (Fig. 3 h). External margins of parameres slightly expanded toward apex (Fig. 3 h). Inner margins subparallel (Fig. 3 h). Endophallus: lamella copulatrix — Projection square-shaped; superior portion slightly curved outward; lateral portion straight (Fig. 10 b). Secondary sexual characters: females differ from males as follows: clypeal and genal surface with strong transversal ridges; clypeal teeth more acute (Fig. 3 c); medial portion of sixth sternite as long as the fifth.
Remarks. In the original description the type locality reported was “Cayennae”, without additional information (Harold, 1867). However, the label of the type species indicates “Nov. Frib.” [Nova Friburgo, Rio de Janeiro] as the type locality. Indeed, D. irinus is distributed in the southeastern parts of the Brazilian Atlantic Forest and Restinga from Bahia, Espírito Santo, Minas Gerais and Rio de Janeiro states. Data from Cayennae probably corresponds to mislabeled specimens.
description: Published as part of Valois, Marcely C., Vaz-De-Mello, Fernando Z. & Silva, Fernando A. B., 2017, Taxonomic revision of the Dichotomius sericeus (Harold, 1867) species group (Coleoptera: Scarabaeidae: Scarabaeinae), pp. 503-530 in Zootaxa 4277 (4) on pages 511-514, DOI: 10.11646/zootaxa.4277.4.3, http://zenodo.org/record/829861