Dichotomius buqueti ( Lucas, 1857 )

Arias-Buriticá, Jorge Armando & Vaz-de-Mello, Fernando Z., 2019, Redefinition and taxonomic revision of the “ buqueti ” species-group, Dichotomius Hope, 1838 (Coleoptera: Scarabaeidae: Scarabaeinae), Revista Brasileira de Entomologia 63 (1), pp. 43-52 : 46-48

Dichotomius buqueti ( Lucas, 1857)

( Figures 4 , 5 A–J, 8A)

Copris buqueti Lucas, 1857 : Page 105 (original description). Pinotus buqueti ( Lucas, 1857) : Page 1009; Gemminger, M., Harold, E., 1869. (Transfer to Pinotus ).

Type Material: Lectotype male (here designed): [1,quadrangular and red label, handwritten] Buqueti mihi, Tridens, Buquet, [2,quadrangular and yellow label, handwritten] 5089. 1♂. [ BMNH] ( Fig. 4 ). Additional specimens (20♂♂. 24♀♀.): BRAZIL: 1♂. [ MZSP] . Minas Gerais: Passa Quatro, Fazenda Dos Campos, 6/ IV / 1914, J.F. Zikan 1♀ [ MZSP]; IX/ 1917 1♀. [ MZSP]; XI/ 1918 1♀. [ MZSP]; 1919 1♂. [ MZSP]. Vila Monte Verde, 15/ IV / 1960, J. Halik. 1♂. [ MZSP]; 17/ III / 1966 1♂. [ MZSP]; 18/ III / 1966, 3♂. [ MZSP]; 18/ IV /1966, 1♀. [ MZSP]; 18/ IV / 1966 1♂. [ MZSP]; 21/ XI / 1966 1♀. [ MZSP]; 23/ II / 1969 1♀. [ MZSP]; 26/ VII /1968 1♀. [ MZSP]. Monte verde, 16/ VII / 1959, Reichard Col. 1♀. [ MZSP] . Passa Quatro, 915m, 2/ IV / 1922, J.F. Zikan 2♂. [1♂. MZSP; 1♂. IBSP] . Rio de Janeiro: Itatiaia, 16/ III / 1989, Godinho, C. 1♂. [ CEMT]; IV/1992, 1♀. [ CEMT]; II/ 1993, 1♂. [ CEMT]; 1/ III / 1993, Celso, J. 1♂. [ CEMT] . Nova Friburgo, Campo Coelho , I/ 1996, Penna, F. 1♂. 1♀. [ CEMT]. Petrópolis, 22/ I /1899. 1♀. [ MZSP] São Paulo: Campos [do] Jordão, 5/ I / 1960, J. Halik. 1♀. [ MZSP]; Campos do Jordão, I/ 2004, Almeidaneta, G.P 1♀. [ CEMT]; 19/ I / 2004, Pereira, E. 1♀. [ CEMT]; 5/ II /2004, Pereira, E. 1♂. 1♀. [ CEMT]; 1800 m, I/ 2005, Pereira, E. 2♀. [ CEMT]. Serra da Bocaina, San Jose do Barro, I-II/ 1960, M.A. Vulcano. 3♂. 8♀. [ MZSP] .

Males: Length 27–37 mm; width 17–21 mm. Black color. Elytra with blue overtones ( Fig. 5A ).

Head: Longer than wide, with prolonged anterior margin giving the appearance of a blunt triangle. Clypeus with a bright flange, without clypeal teeth. Surface of clypeus with strong, parallel wrinkles. Genae with curved andpronounced anterior edge, lateral edge straight and then curved, surface with strong wrinkles. Clypeusgenal suture evident, reaching the cephalic process. Frons with three horns; the central and most close to back edge looking like a prolonged “C”, dorsoventrally flattened in the basal region at lateral view, in the second-third getting compressed and ending with a cylindrical, brilliant and blunt tip; in frontal view it shows a central keel. The lateral horns are conical, with 2 mm or more, wide base and ending with cylindrical, brilliant and blunt tips, directed upwards and diagonal to the base of the central horn, reaching its middle.

Thorax: Pronotum twice as wide as long. Surface with circular punctures, elongated toward the lateral margins and are separated bytwice orthreetimestheir length.Anterior regionwith a wide and smooth edge, which gets compressed toward the anterior angles. The anterior angle is curved forming an angle of approximately 90 ◦. In side view of pronotum, the anterior region is vertical to the dorsal region, straight in the central region and curved toward the lateral region. Pronotum with two short and curved tubercles on the central region; from these tubercles come two protuberances like humps toward the lateral zones giving the appearance of an excavation at the anterior area of the pronotum. Behind and between both tubercles, there is an elongated and deep fovea that reaches the posterior region of the pronotum. Both lateral foveae are big, deep and dorsiventrally enlarged. Hypomere with shagreened surface and dense setigerous punctures; lateral edges with erect, long and brown setae which can be seen at dorsal view and less dense at the central region where they are separated by twice their diameter. At the central region under the femur, the surface is smooth and brilliant. Shagreened prosternum with setigerous punctures prolonged from its medium region until covering the antero-medial zone of the mesosternum. From the posterior edge of the prosternum emerge many yellow setae directed toward the mesosternum. Elytra with soft and bicarinate striae, with ocellated puncturesspacedby about five timestheir diameter; the base of the first five striae has an irregular fovea. Interstriae with shagreened surface with very soft punctures separated between them by seven times their diameter observed at 20 ×. In some specimens there are transverse wrinkles near to the striae. Mesosternum strongly narrowed medially, on which there is a brilliant and smooth process that precludes seeing the meso-metasternal suture, there is a shagreened surface toward the sides with setigerous punctures and yellow setae. Mesepisternum with the same surface as the lateral edges of the mesosternum. The meso-metasternal suture is erased in the central area by a mesosternum process, lateral margins are evident and brilliant. Metasternum with shagreened, shiny central area without setae; strong carina from 1/3 of metasternum to the back ending in a deep fovea. Side edges of the anterior area shagreened with dense setigerous punctures, posterior area shagreened with large setigerous punctures. Metepisternum equal to mesepisternum.

Abdomen: Sternites shagreened with some soft and separated punctures, evident in the 5th and 6th sternites. Lateral edges of all sternites with dense ocelated punctures. 6th sternite very narrowed medially. Pygidium shagreened with elongated and separated punctures at least twice its diameter, incomplete margin in the middle inferior region.

Male genital organ: Side view of aedeagus with sub-quadrangular phallobase, basal zonewith a mediumbulgeatbothsides, apexwith a constriction of approximately 115 ◦. Sub-triangular parameres with a thin prolongation at the inferior base, which continues with an invagination toward the middle zone; apex thin, blunt, with a flat surface where long and yellow setae emerge ( Fig. 5B ). Dorsally symmetric with enlarged baseand becoming thinnertoward apical zone atwhich ending with a blunt tip; in this view setae can be seen too. Internal region with a convex invagination toward the middle until the apical region of each paramere ( Fig. 5C ). In the ventral view, parameres are thin at the basal zone with an acute prolongation described in the lateral view: apex blunt and flat where setae can be seen. Between parameres and inserted from the apical to the basal zone by a membrane, there are two lamellated and overlapped processes, that of the left paramere over that of the right paramere ina characteristic waywhich goesfrom the apical zoneto beyond two-thirds of the parameres ( Fig. 5D ). Internal sac tubular with raspules at basal 1/3; at the center one big, sub-quadrangular, browncolor copulatrixlamellae with twolateral tubularanddarker prolongations, whole surface covered by bristles which become longer toward lateral margins ( Fig. 5E ). Apical zone with three accessorylamellae, onelong andcentralwith undefined form, more sclerotized in the central area with a surrounding semi-quitinized membrane ( Fig. 5F ). Left lateral lamella has “C” form, with a flat base, well sclerotized with irregular borders ( Fig. 5G ). Right lateral lamella has “N” form, enlarged, sclerotized in the center and surrounded by a semi-quitinized membrane ( Fig. 5H ).

Female: length 26.5– 37 mm; width 16.8–21.1 mm. It differs from males by presenting a more defined clypeus edge. Frons with a four pointed cephalic process; both central tips higherand attached, lateralones conicalandsmaller ( Fig. 5I ). Centraltuberclesof pronotum are softer ( Fig. 5J ). 6th abdominal sclerite not shortened medially.

Commentaries: The species is distinguished from the others of the group “buqueti” because the males present a process of three horns in the front where the two lateral horns have two or more mm and the females with four pointedcephalic process, pronotum with two short and curved tubercles on the central region and elytra with blue overtones. The species is associated with areas of Atlantic forest with altitudes of between 900 m and 1200 m in the mountains of Mantiqueira and Órgãos in Brazil.

Distribution: This species is distributed in Brazil in the São Paulo, Rio de Janeiro and Minas Gerais states ( Fig. 8 ).

Figures

Fig. 4. Dichotomius buqueti. Labels of Lectotype here designated.

Fig. 5. Dichotomius buqueti. (A) Dorsal habitus of the male. (B) Lateral view of aedeagus. (C) Dorsal view of parameres. (D) Ventral view of the parameres. (E) Copulatrix lamellae. (F) Central accessory lamella. (G) Left lateral accessory lamella. (H) Right lateral accessory lamella. (I) Head of female. (J) Thorax of female. Line scale 1 mm.

Fig. 8. Distribution maps of the “buqueti” species group.