A taxonomic revision of the genus Scybalocanthon Martínez, 1948 (Coleoptera Scarabaeidae: Scarabaeinae: Deltochilini) Author Silva, Fernando A. B. Universidade Federal do Pará, Instituto de Ciências Biológicas, setor de Zoologia, Campus Belém. Rua Augusto Corrêa, 01. Guamá. Belém PA 66075 - 110, Brazil. E-mail: fernandoabsilva @ yahoo. com. br Author Valois, Marcely Programa de Pós-graduação em Zoologia, Universidade Federal do Pará / Museu Paraense Emílio Goeldi. Rua Augusto Corrêa, 01. Guamá. Belém PA 66075 - 110, Brazil. text Zootaxa 2019 2019-07-08 4629 3 301 341 journal article 21174 10.11646/zootaxa.4629.3.1 9419bc9b-dbe4-426c-a34e-f0034848ff99 1175-5326 3995508 1D47B452-0A40-4BC5-9BBA-C06DEB298C9A Scybalocanthon federicoescobari Silva & Valois , new species ( Figs. 1I , 4I , 5H , 6D ) Etymology. Named in honor of Federico Escobar, a scarab ecologist who was responsible for collecting the type specimens. Diagnosis . Specimens of S. federicoescobari are similar to those of S. arnaudi , S. martinezi , S. papaxibe , S. pinopterus , and S. uniplagiatus by having the pronotum uniformly colored, or with one elliptical spot on the central portion ( Figs. 1I , 2A , 1P , 2K , 1D, 1T ); femora almost completely yellow or brown, with black spots only on the tips ( Fig. 3G ); eighth elytral stria with thin carina on anterior portion ( Fig. 3D ); endophallus with bristles right beside the FLP sclerite ( Figs. 5H, R, N, W, D, Q ); and additional sclerite ( AS ) absent ( Figs. 5H, R, N, W, D, Q ). They can be distinguished from those of S. pinopterus and S. arnaudi by the strongly asymmetrical parameres; left paramere with acute projection on dorsal margin and bilobate excavation on ventral margin ( Fig. 4I ) (other species with slightly asymmetrical parameres, lacking acute projection and bilobate excavation on dorsal and ventral margins, respectively ( Figs. 4E, 4S )); from those of S. martinezi , S. papaxibe , and S. uniplagiatus by the bilobate excavation of the ventral margin of the left paramere deeper than wide in lateral view, extending along one-fourth of the paramere margin ( Fig. 4I ) (in S. martinezi the bilobate excavation is wider and deeper, extending at least one-half of the paramere margin ( Fig. 4O ); in S. uniplagiatus its excavation extending along one-third of the paramere margin ( Fig. 4W ); in S. papaxibe its excavation is wider than deep in the lateral view ( Fig. 4R )). Description. Body. Oval-elongate. Surface opaque, completely microgranulate. Color . Most of pronotum, hypomera, metaepisternae, metaventrite, abdominal ventrites, pygidium, and femora yellow or light brown. Head, elytra, prosternum, mesoventrite, mesoepisternae, trochanters, and tibiae dark brown. Length. 7.8–9.5 mm . Thorax . Pronotum with one brown rounded spot at the anterocentral portion. Spot elliptical in some specimens.Anterior angles of pronotum approximately 85°. Lateral margin regularly curved outward, not forming an angle at the middle portion. Elytra . Striae thin and shiny, punctures inconspicuous. Eighth stria with a thin carina at the anterior portion. Aedeagus. Parameres strongly asymmetrical ( Fig. 4I ). Dorsal margin of right paramere curved inward, apex obliquely truncate. Ventral margin of right paramere substraight, with a rounded excavation at the basal portion. Dorsal margin of left paramere curved inward from the basal to medial portions, apical portion with a short and pointed projection. Ventral margin of left paramere substraight, with a bilobate excavation at the basal portion, apical portion pointed. SRP circular, with rounded handle-shaped extension ( Fig. 5H ). FLP short, comma-shaped, with three sets of bristles right beside it ( Fig. 5H ). A+SA with two superposed and elongate sclerites ( Fig. 5H ). Type material. Holotype . COLOMBIA : GUAVIARE , Reserve Nukak , Cerro Moyano ( 71°10’58”W , 02°10’35”N ), II.1996 , pitfall human feces, 250 m , F. Escobar— 1♂ ( CEMT ) . Paratype . COLOMBIA : GUAVI- ARE , Reserve Nukak , Cerro Moyano ( 71°10’58”W , 02°10’35”N ), II.1996 , pitfall human feces, 250 m , F. Esco-bar— 1♀ ( CEMT ) . Distribution. Known from Colombia ( Fig. 6D ). Endemism areas : Brazilian sub-region : Boreal Brazilian dominion: Imeri province (see Morrone 2014 ; fig. 12).