Gracilaclopus bidentulus Ocampo & Mondaca

Ocampo, Federico C. & Mondaca, José, 2012, Revision of the scarab subfamily Aclopinae Blanchard (Coleoptera: Scarabaeidae) in Argentina and Chile, Zootaxa 3409, pp. 1-29 : 7-9

Gracilaclopus bidentulus Ocampo & Mondaca , new species

( Figs. 5–7 , 23 , 31 )

Diagnosis. This species is distinguished from the other species of Gracilaclopus by the following combination of characters: clypeus with tooth-like process on anterior angle; labral apex with two well developed teeth ( Fig. 5 ); body bicolored with scutellum same color as elytra; size <5 mm; male genitalia as Fig. 23 .

Description. Holotype male. Length 4.53 mm, width 2.07 mm. Color: Head dark brown, pronotum brown; elytra light brown; legs, antennae, and mouthparts brown; ventral surface brown. Head ( Fig. 5 ): Frons slightly concave on apical half, convex at base; surface punctate, glabrous. Clypeus strongly transverse; lateral margins oblique, reflexed, with tooth-like process on anterior angle; anterior margin straight, slightly reflexed; frontoclypeal suture obsolete, surface densely punctate, sparsely setose. Labrum glabrous, shape subrectangular in dorsal view, apex with two large teeth, teeth strongly reflexed. Pronotum ( Fig. 6 ): Convex, wider than long. Surface sparsely punctate, with few setae, setae long, slender. Marginal bead present in all margins. Anterior angle nearly right-angled; posterior angles broadly rounded. Scutellum: Large , triangular, apex rounded, surface punctate at base, smooth at apex. Elytra: Surface punctate, punctures sparse, setose; setae moderately long. Legs: Mesotibia with two transverse carinae, metatibia with one transversal carina. Mesotibial and metatibial apex with fringe of spine-like setae. Male genitalia: Parameres as long as phallobase, broadly curved, apex club-like ( Fig. 23 ).

Allotype female. ( Fig. 7 ). As holotype except: Length 4.58 mm, width 2.35 mm. Color: Head, pronotum, elytra, venter, legs light brown. Eyes small, not visible dorsally. Eye canthus strongly reduced. Antennal club small. Elytra short, approximately as long as wide (both elytra combined). Five visible abdominal segments, pygidium and 3 abdominal segments exposed beyond elytral apex. Metatibiae longer than metatarsi. First metatarsomere shorter than metatibial spurs.

Remarks. Males vary slightly in length (3.27–4.68 mm, width 1.33–2.17) and color; the shape of the labral teeth varies in length and development among specimens.

Type material. Holotype male at CMNC labeled: “ Argentina / Córdoba / D° Cruz del Eje / Guanaco Muerto / Col. Martínez / Feb 1980 ”; “ Gracilaclopus / bidentulus / Ocampo & Mondaca / HOLOTYPE ” (red holotype label). Allotype female at IAZA labeled: “R.A. Cba / Chancaní / Octubre 1992 / Col. Molina ” “A311 /10-92 / 371”; “30005”; “ Gracilaclopus / bidentulus / Ocampo & Mondaca / ALLOTYPE” (red allotype label, handwritten).

Paratypes (all male). Three paratypes (two at CMNC and one at IAZA) labeled as holotype except for paratype label. Four male paratypes (three at CMNC and one at IAZA) labeled: “Quimilí, S. del Estero / 9-XII-1939 / Birabén - Bezzi col.” Four paratypes (three at CMNC and one at IAZA) labeled: “ ARGENTINA / La Rioja / D° Peñaloza / Olta (Illiar) / Coll / Martínez / Nov. 964” Three paratypes (two at IAZA and one at GASC) labeled: “ ARGENTINA: Córdoba / Cruz del Eje 4/III/2000. / G. Arriagada”. One paratype at CMNC labeled: “ Argentina / Salta / D° San Martín / Pocitos / coll. Martínez / Dic. 974.

All paratypes labeled: “ Gracilaclopus / bidentulus / Ocampo & Mondaca / PARATYPE ” (yellow paratype label).

Type locality. Argentina, Córdoba, Guanaco Muerto.

Etymology. The name “ bidentulus ” refers to the two well developed teeth on the labrum of this species.

Distribution ( Fig. 31 ). ARGENTINA: Córdoba: Chancaní (4), Cruz del Eje (3), Guanaco Muerto (4). La Rioja: Olta (4) Salta: Pocitos (1). Santiago del Estero: Quimilí (4).

Temporal distribution. February (4), March (3), October (4), November (4), December (5).

Figures

FIGURE 7. Gracilaclopus bidentulus, female.

FIGURE 31. Distribution map of Gracilaclopus bidentulus, G. caceresi, G. c a n d e l a r i a e, and G. crepuscularis.

FIGURES 5 – 6. Gracilaclopus bidentulus, male.

FIGURES 23 – 30. 23) Male genitalia of G. bidentulus, aedeagus lateral view; 24) G. c a c e re s i, aedeagus lateral view; 25) G. candelariae, aedeagus lateral view; 26 a – b) G. crepuscularis, aedeagus lateral and frontal views respectively; 27 a – c) G. electricus, a – b) aedeagus lateral and frontal views, c) ventral plate of the genital segment; 28) G. m o ro c h u s, aedeagus lateral view; 29) G. nigroscutatus, aedeagus lateral view; 30) G. parvulus, aedeagus lateral view.