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 martinezi Silva & Valois , new species ( Figs. 1P , 4O , 5N , 6D ) Etymology. Named in honour of Antonio Martínez, for his description of Scybalocanthon and his valuable contributions towards the taxonomy of the genus. Diagnosis . Specimens of S. martinezi are similar to those of S. arnaudi , S. federicoescobari , S. papaxibe , S. pinopterus , and S. uniplagiatus by having the pronotum uniformly colored, or with one elliptical spot on the central portion ( Figs. 1P , 2A , 1I , 2K , 1D, 1T ); femora almost completely yellow or brown, with black spots only on the tips ( Fig. 3G ); eighth elytral stria with thin carina at the anterior portion ( Fig. 3D ); endophallus with bristles right beside the FLP sclerite ( Figs. 5N, R, H, W, D, Q ); and additional sclerite ( AS ) absent ( Figs. 5N, R, H, 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. 4O ) (other species with slightly asymmetrical parameres, lacking acute projection and bilobate excavation on dorsal and ventral margins, respectively ( Figs. 4S, E )); from those of S. federicoescobari , S. papaxibe , and S. uniplagiatus by the bilobate excavation of ventral margin of left paramere wide and deep, extending at least one-half of the paramere margin in the lateral view ( Fig. 4O ) (other species with a short bilobate excavation, not reaching one-half of paramere margin in the lateral view ( Figs. 4I, W, R )). Description. Body. Oval-elongate. Surface opaque (except pronotum), completely microgranulate. Color . Most of pronotum, hypomera (except internal margin), metaventrite, abdominal ventrites, pygidium, middle of femora, and tibiae yellow or light brown. Head, internal margin of hypomera, prosternum, mesoventrite, mesoepisternae, metaepisternae, elytra, trochanters, and proximal and distal portions of femora dark brown. Length. 8.5 mm . Thorax . Pronotum with one brown rounded spot at the anterocentral portion ( Fig. 1P ). In some, spot absent. Anterior angles of pronotum approximately 80°. Lateral margin regularly curved outward, not forming an angle at the middle portion. Elytra . Striae thin and shiny, punctures conspicuous. Eighth stria with a thin carina at the anterior portion. Aedeagus. Parameres strongly asymmetrical ( Fig. 4O ). 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 from the basal to medial portions. SRP circular, with rounded handle-shaped extension ( Fig. 5N ). FLP short, comma shaped, with three sets of bristles right beside it ( Fig. 5N ). A+SA with two superposed and elongate sclerites ( Fig. 5N ). Type material. Holotype . ECUADOR : NAPO : Daimi 1, Bosque Sendero , 20.ix.1989 , pitfall , Sandoval— 1♂ ( CEMT ) . Paratypes [ 19 males , 18 females ] . ECUADOR : NAPO : Scyasuni , 20–21.x. 1997 , 200 m, D. Padilla & I. Tapin— 1♀ ( CEMT ) . COLOMBIA : AMAZONAS, Leticia , 215 m ( 4°11’20’’S , 69°56’9’’W ), 10.vii.1970 , H. & A. Howden— 3♂ 1♀ ( CMNC ); Leticia, 215 m ( 4°11’20’’S , 69°56’9’’W ), 19–25.ii.1972 , H. & A. Howden— 1♀ ( CMNC ); Leticia, 215 m ( 4°11’20’’S , 69°56’9’’W ), 20–25.ii.1972 , Peck & Howden , dung traps— 10♂ 4♀ ( CMNC , MZUFPA ); Los Alpes, Leticia, 213 m ( 4°4’25’’S , 70°0’5’’W ), 23.ii–iii.1974, S. Peck , dung trap— 2♂ 10♀ ( CMNC ); road end, Leticia, 213 m ( 4°4’9’’S , 69°59’56’’W ), 23.ii–2.iii.1974 , S. Peck , dung trap— 4♂ 1♀ ( CMNC ) . Distribution. Known from Ecuador and Colombia ( Fig. 6D ). Endemism areas : Brazilian sub-region : Boreal Brazilian dominion: Napo and Imerí provinces (see Morrone 2014 ; fig. 12).