Aphengium curtum, Silva, Fernando A. B. & Vaz-De-Mello, Fernando, 2015

Silva, Fernando A. B. & Vaz-De-Mello, Fernando, 2015, A revision of the genus Aphengium Harold, 1868 (Coleoptera: Scarabaeidae: Scarabaeinae: Ateuchini), Zootaxa 3955 (4), pp. 505-520 : 511

Aphengium curtum sp. nov.

( Figs 25–30 , 34 , 40, 41)

Etymology. The epithet is a Latin adjective referring to the short body that characterizes this species.

Diagnosis. Immediately distinguished from all remaining species of Aphengium by the following characters: short body (6–7 mm); head and disc of pronotum, in dorsal view, with smooth and sleek surface or punctures almost inconspicuous ( Figs. 27–30 ); anterolateral portion of pronotum with a longitudinal and sleek callus ( Figs. 29, 30 ). Furthermore, the aedeagus morphology and the fronto-lateral peripheral sclerite (FLP) are unique among Aphengium species ( Figs. 34 , 40).

Description. Length. Small (6–7 mm) ( Figs. 25, 26 ). Head. Dorsal surface smooth and sleek, with short and almost inconspicuous setae; lacking foveiform punctures or coarse, scattered and weakly impressed ( Fig. 27 ). Pronotum. Foveiform punctures only present on some lateral and posterior portions, not contiguous, usually separated by distance equivalent to more than one puncture diameter ( Figs. 29, 30 ). Disc smooth, sleek and convex. Anterolateral portion of pronotum, between anterior angle and lateral fovea, with a longitudinal and sleek callus ( Figs. 29, 30 ). Anterior and lateral angles of pronotum greater than 90°. Margin between lateral and posterior angles straight. Elytra. Rounded shape ( Figs. 25, 26 ). Disc convex, with minute and almost inconspicuous setae. Lateral margins curved outwards. Foveiform punctures separated on the elytral disc by distance equivalent to at least three puncture diameter. Secondary sexual characters. Besides the sexual dimorphism described for the genus, females differ from males in the following aspects: dorsal surface around clypeus slightly rugose, with weakly impressed punctures ( Fig. 28 ). Aedeagus. Length of parameres longer than one-half that of phallobase. Dorsal and ventral margins of parameres almost straight; apex acuminate ( Fig. 34 ). Superior right peripheral sclerite (SRP) sigmoid. Fronto-lateral peripheral sclerite (FLP) as in figure 40.

Material studied. Holotype. BRAZIL: BAHIA: Itabuna, Cabruca veg. type, [39°16’38”W, 14°47’20”S], 07.I.2003, M. S. Santos (1♂ CEMT). Paratypes [34]. BRAZIL: BAHIA: Ilheus, Universidade Estadual de Santa Cruz ( UESC), [39°10'20"W, 14°47'45"S], 19.V.2000, V. A. Melo (1♂ 3♀ CEMT); Itabuna, Cabruca veg. type, [39°16’38”W, 14°47’20”S], 07.I.2003, M. S. Santos (10♂ 6♀ CEMT); Itapetinga, Mata Seca veg. type, [40°14’55”W, 15°14’58”S], 05.II.2009, pitfall hum. faeces, J. G. Mota-Souza (12 CEMT; 2 CERPE).

Distribution. This species is known only from forest patches around Ilhéus in the center of the coastal region of Bahia state. At least two of those patches are either Cabruca vegetation type (agricultural area where the cacao is planted in the midst of the natural vegetation of Atlantic forest) or secondary growth.

Figures

FIGURES 25 – 30. Aphengium curtum sp. nov.; 25. Male (dorsal view); 26. Female (dorsal view); 27. Male head; 28. Female head; 29. Male pronotum (arrow shows anterolateral portion of pronotum with a longitudinal and sleek callus); 30. Female pronotum.

FIGURES 31 – 34. Aedeagus of Aphengium; 31. A. sordidum (arrow shows dorsal margin of parameres curved inward at its apical third); 32. A. cupreum; 33. A. ibateguara sp. nov.; 34. A. curtum sp. nov.