Dichotomius (Selenocopris) paresi, Nunes, Rafael V. & Vaz-De-Mello, Fernando Z., 2016

Nunes, Rafael V. & Vaz-De-Mello, Fernando Z., 2016, New brachypterous species of Dichotomius (Selenocopris) Burmeister (Coleoptera: Scarabaeidae: Scarabaeinae) with the definition of species groups and taxonomic notes in the subgenus, Zootaxa 4139 (1) : -

Dichotomius (Selenocopris) paresi new species

( Fig. 6 )

Material studied. Holotype: Ƌ BRASIL: Mato Grosso: Nova Marilândia. Fazenda Aparecida da Serra. 14°21’14”S; 57°43’54”W. Human feces. 17-I-2010. RJSilva (leg.) / Dichotomius paresi n. sp., holotype. RVNunes & FZVaz-de-Mello, 2011 [ CEMT]. Paratypes: same data of holotype [2 Ƌ, 2♀, CEMT]; Nova Marilândia, 2008.

Cerrado sensu stricto. Pitfall s/ isca. Tombo 13 [7 Ƌ, 2♀ CEMT]; Same but Fazenda Aparados da Serra. 14°22’01”S; 57°43’30”O. 575mosl. Cerrado s. str. Pitfall s. isca. 8- 16-II-2 0 0 8 [2 Ƌ 1 ♀ CEMT]; same but 30 km NW Tangará da Serra. 3–9.XII.2012. Vaz-de-Mello, Pokorný & Beneč [5 Ƌ SPPC].

Diagnosis. In the group, D. paresi n. sp. is separated of other species in the group (including the brachypterous) by the following combined characters: posterior portion of the pronotal disc bearing ocellate punctures ( Figs. 6 A–B); elytral striae widened near the basis and lacking punctures ( Fig. 6 E) and anterior portion of pronotal border flattened (dorsal view) ( Figs. 6 A–B).

Holotype. male: length: 17.0 mm. Maximum width (pronotum): 10.5 mm. Black, shinny. Head: dorsal surface smooth, bearing few occellate puncturess close to the internal border of the eyes. Clypeogenal junction obtuse. Margins of clypeal teeth bearing a single row of short scattered setae. Ventral clypeal process strongly bifurcated. Cephalic process smooth, consisting of a single conical horn. Clypeo-genal suture distinct, producing a posterior knob. Antennal club with dark brown tumescence. Pronotum: wider than long and sub equal to elytra on width. Anterior excavation bearing ocellate punctures very close to each other. A bilobed projection delimits the pronotal disc from the anterior declivity. Pronotal disc shining: smooth anteriorly and bearing ocellate punctures posteriorly – the diameter of the punctures increase toward the posterior margin of pronotum. Ocellate punctures also present on pronotal margins and at the anterior angles. Anterior angles acute. Anterior portion of pronotal sides flattened (dorsal view). Hypomeron: anterior portion with a lateral band of ocellate setose punctures. Posterior portion almost glabrous with few sparse ocellate setose punctures. Prosternum: with ocellate setose punctures: setae do not reach one quarter the length of hypomeron setae. Mesosternum: strongly narrowed, glabrous and chagrinated medially. Mesepisternum: having ocellate setose punctures. Posterior portion of upper margin ending in an acute angle and reaching pseudoepipleuron ( Figs. 1 B–C). Metasternum: mesometasternal suture indistinct. Anterior lobe strong narrowed medially. Ocellate setose puncture present along the margins of the metasternal lobe – these points became denser around the anterior margin. Mestasternal disc bearing a longitudinal sulcus that ends in a feeble posterior concavity. Elytra: black, shinny, lacking humeral callus. Striae widened near the elytral basis, lacking punctures, at most with some indication of points near the elytra apex ( Fig. 6 E). Elytral interstriae feebly convex. Hind wings: length: 11mm. Having folding articulation. Basal sclerites glabrous. Subcostal vein intersecting costal axis at its basal quarter. Medial vein extending to the folding articulation. Distinct setae present on the basal third of costal axis and on folding articulation. Cubital vein present, anal vein absent. Small developed membranous portion apical to folding articulation with incomplete or weakly-marked venations. Legs: anterior tibiae spur curved inward at apical third. Anterior tibiae bearing four teeth. Ventral surface of the anterior femur glabrous. Length of 5th metatarsomere twice the length of 4th metatarsomere. Abdomen: sternites 1 to 6 glabrous and having ocellate punctures on the upper margin. Pygidium: shinny, lacking punctures, wider than long. Paramera: (as in Figs. 6 C–D) having rounded/circular excavations near the basis (dorsal view) and longitudinal excavation toward the apex (lateral and dorsal view). Anterior border of circular/ rounded excavation carinates. Longitudinal excavation taking 1/3 the length of paramera. Apex divergent, curved outward (dorsal view).

Morphological variation. length varies from 17.0– 17.5 mm on males and from 17.5–18.0 mm on females. Pronotum width varies from 10.5–11.5 mm on males and from 10.5–12.0 mm on females. Both males and females show variations in following characters: head: height of the clypeo-frontal carina. Pronotum: anterior declivity may vary in size: on most of the females, the declivity is lower. Also on females, ocellate punctures at anterior lobe are more sparse and smaller (3/4 the diameter of the male biggest occellus). Elytra: both males and females have variations on the color of the elytra base that may exhibit brown reflections. Abdomen: only on females, the sixth abdominal segment has a pair of central tubercles vertically oriented ( Fig. 1 A)

Distribution. Known from the region of Chapada dos Parecis, municipalities of Nova Marilândia and Tangará da Serra, state of Mato Grosso, Brazil ( Fig. 8 ).

Etymology. The species is named after the region that covers the type-locality known as Chapada dos Parecis (Parecis plateau, usually spelled with “c”) at the brazilian states of Mato Grosso and Rondônia. Paresi (spelled with “s”) is also the denomination of the ethnic groups living at the same region.

Remarks. this is the only species of Selenocopris that bears ocellate punctures on the pronotal disc and the unique in the quadraticeps group that lacks punctures in the elytral striae. Among the brachypterous species in the group, the male paramera is most similar to D. manni while the males head and pronotum characters are shared with D. ingens and D. fissiceps . Dichotomius paresi has been collected at open habitat (cerrado sensu stricto formation) at Paresi Plateau, which takes part of the states of Mato Grosso and Rondônia. Ecologically, this species is similar to D. ingens , both were collected at open habitats, at the hottest hours of the day (between 11:00 and 13:00) and being mostly attracted to carrion.

Figures

FIGURE 1. (A) Ventral habitus of a female of Dichotomius (Selenocopris) periotoi n. sp. The white arrow at the head indicates the position of the ventral clypeal process and the white at the abdomen indicates the modification at the medial portion of the 6 th sternite; (B) lateral view of the same specimen. The white arrow indicating the position of the mesepisternum.; (C) detail of the mesepisternum of the same specimen. The white arrow indicates the posterior portion of the upper margin of the mesepisternum ending in an acute angle, which is typical of Selenocopris; (D) elytral striae and interstriae of D. (S.) fissus (Gillet); (E) elytral striae and interstriae of D. (S.) fissiceps (Felsche) (quadraticeps group); (F) head and clypeal teeth of D. (S.) bicuspis (Germar); (G) head and clypeal teeth of D. (S.) fissiceps (quadraticeps group); (H) 6 th abdominal sternite of the female of D. (S.) spadiceus (Luederwaldt); (I) 6 th abdominal sternite of the female of D. (S.) punctulatipennis (Luederwaldt) (bicuspis group); (J) 6 th abdominal sternite of the male of D. (S.) ascanius (Harold); (K) 6 th abdominal sternite of the female of D. (S.) ascanius (Luederwaldt); (L) 6 th abdominal sternite of the female of D. (S.) quadraticeps (Felsche).

FIGURE 6. Paratypes of Dichotomius (Selenocopris) paresi n. sp.: (A) male dorsal habitus; (B) female dorsal habitus (black arrows indicate the ocellate punctures at the posterior portion of the pronotal disc); (C) dorsal view of male paramera; (D) lateral view of male paramera; (E) detail of elytra, white arrow indicating the elytral striae widened near the basis. Scale bar = 5 mm.

FIGURE 8. Distribution of the brachypterous species of Selenocopris.