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

Vaz-De-Mello, Fernando Z. & Nunes, Rafael V., 2016, New species, redescription and taxonomic notes in the Dichotomius (Luederwaldtinia) batesi (Harold) species-group (Coleoptera: Scarabaeidae: Scarabaeinae), Zootaxa 4139 (2), pp. 294-300 : 295-297

Dichotomius (Luederwaldtinia) benesi n. sp.

Fig. 1

Material studied: Holotype: Ƌ PANAMA: Veraguas: Santa Fé, 811 m, 8°29'N, 81°06'W, 16-18-VI-2013. V Benes lgt [ CEMT]. Paratypes: same data as holotype [10 Ƌ, 7 ♀ CEMT]; same but Safanda lgt [1Ƌ, 3 ♀ CEMT; 2 Ƌ 9 ♀ SPCP]; same but iv-v-2014, V Benes lgt [1 Ƌ 1 ♀ CEMT].

Diagnosis: Dichotomius . benesi n. sp. belongs to the subgenus Luederwaldtinia due to the following combined characters: two clypeal teeth; ventral clypeal process bifurcated; clypeo-genal junction rounded, lacking angulation; abdominal ventrites having setae; last abdominal sternite of females simply widened, lacking tubercles or projections (Vaz-de-Mello et al. 2011; Nunes & Vaz-de-Mello 2013). Among this subgenus, it is assigned to the batesi species-group since its pronotal disc bears ocellate punctures all over its extension and males calcar is not sickle-shaped.( Luederwaldt 1929, Pereira 1947, Nunes & Vaz-de-Mello 2013). This new species is differentiated from the others of the group by the combination of the following characters: atrophied hind wing lacking the anal vein and never having more than the elytra length; pronotal disc punctures equally spaced; cephalic process consisting of a unique central tubercle; longitudinal groove present along all the posterior margin of the meso and meta femura; elytral striae lacking punctures and apexes of the paramera membranous.

Holotype: male, length: 14 mm. Pronotum width: 8 mm. Dorsal and ventral surface barely shinny, black. Head: anterior margin of the clypeous with a deep “u” shaped emargination forming two rounded teeth. Clypeogenal junction rounded, not angulating. Clypeal surface smooth at the front and with ocellate punctures anteriorly and laterally. Gena and intraocular space also bearing ocellate punctures equally spaced. Clypeo-genal suture present. Cephalic process consisting of a small central tubercle. Antenal club with brown light tumescence. Pronotum: wider than long and wider than elytra. Lacking knobs, horns or excavations. Pronotal disc strongly convex with ocellate punctures equally spaced by their diameter. Posterior margin bearing ocellate elliptical punctures larger than those found on the rest of the pronotum. Anterior angles acute. Hypomeron: whole structure covered by ocellate setose punctures—setae short, scattered and not present in all punctures. Prosternum: bearing ocellate punctures all over its extension. Mesosternum: also bearing ocellate punctures almost all over its extension, except at the middle, where is narrower, smooth and shinny. Metasternum: with few scattered setae, almost glabrous. Mesometasternal suture distinct. Anterior portion of the metasternal lobe bearing ocellate punctures. Anterior lobe width half the length of metafemur. Longitudinal sulcus feebly marked. Fine punctures present near the region between metacoxae. Metasternal sides bearing ocellate punctures similar to those found at the prosternum, mesosternum and sides of the abdominal segments. Elytra: having humeral callus and strongly convex at lateral view. Striae ill defined and lacking distinct punctures. Interstriae with chagrinated microsculpture (20x). Hind wing: length 8 mm. Cubital venation interrupted and anal vein absent. Legs: anterior tibiae bearing four teeth. Anterior calcar curved at the apical third, posterior calcar emarginated. Ventral surface of the anterior femur bearing ocellate setose punctures all over its extension—setae short, sparse and not present in all punctures. On the medium and posterior femur these punctures are restricted to their apical portion. Meso and meta femur bearing a longitudinal groove almost all over its extension—this sulcus gets wider as it goes to the distal part. Abdomen: abdominal sternites with short-scattered setae mainly concentrated on sides; ocellate punctures present close to the anterior margin. Pygidium: twice wider then long and covered by ocellate coarse punctures. Phalobasis: apex broadly arcuate, anterior angles acute. Paramera: on dorsal view, each paramere is strongly narrowed medially. Apexes truncated and membranous. On lateral view, apex of the paramera bent downward.

Morphological variation. This species has few variations, those are mainly related to the body length (12- 14mm) and pronotum width (7–8 mm). Females are distinguished from males by the sixth abdominal sternite—that has more than twice the width than any other abdominal ventrite.

Distribution. Santa Fé in Veraguas province in Panama.

Etymology. Named after Vladimir Beneš, Czech scarab and carabid collector and friend, who collected most of the type series.

Remarks. D. benesi n. sp. is close to D. gamboensis and D. femoratus , both described from Panama at lower altitudes ( Howden & Young 1981). These three species share the following characters: central unique tubercle on the head; pronotal disc punctures equally spaced; chagrinated elytral interstriae; longitudinal sulcus along the posterior margin of meso and metafemura; apexes of the paramera membranous on dorsal view and apexes of the paramera and bent downward on lateral view ( Fig. 1 D, 1E). However, the pronotum of D. benesi is wider than elytra and the hind wing lack the anal vein; both characteristics are related to the absence of hind wing.

Figures

FIGURE 1. (A) Dorsal habitus of the males of Dichotomius (L.) benesi n. sp. (B) Ventral habitus of the male of D. benesi. (C) Dorsal habitus of the female of D. benesi. (D) Dorsal habitus of the male genitalia of D. benesi. (E) lateral habitus of the male genitalia of D. benesi.