Taxonomic revision of the Deltohyboma Lane, 1946 gilli species group (Coleoptera: Scarabaeidae: Scarabaeinae: Deltochilum) Author González-Alvarado, Arturo 2D58A702-73A9-4C66-8CED-6B8B9A2AB10B Programa de Pós-graduação em Ecologia e Conservação da Biodiversidade, Universidade Federal de Mato Grosso, Cuiabá, Mato Grosso, Brazil. fagakorn@gmail.com Author Vaz-De, Fernando Z. 2FF2B7D6-1A6B-43C1-9966-A1A949FB2B05 Instituto de Biociências, Departamento de Biologia e Zoologia, Universidade Federal de Mato Grosso, Cuiabá, Mato Grosso, Brazil. vazdemello@gmail.com text European Journal of Taxonomy 2021 2021-10-20 775 86 106 journal article 3948 10.5852/ejt.2021.775.1551 cc10c087-bec3-4947-81d7-b3e5580a5c94 2118-9773 5589689 976D7020-5904-4951-97CE-B4FE58DA12A8 Identification key to species of the gilli species group 1. Striae I–VII inconspicuous, including apically, only in some parts striae slightly visible and very narrow ( Fig. 4B–C )............................................................................................................................ 2 – Striae I–VII conspicuous ( Fig. 4A, D–E ) .......................................................................................... 3 2. Head punctures on frons separated by less than one diameter of a puncture ( Fig. 2B ). Pronotal disc punctures separated by less than one diameter ( Fig. 3B, F ). Pronotal disc with well-defined shiny points ( Fig. 3F , white arrows). Punctures of third interstria on disc occupying about 1/14 th the distance between striae II and III ( Fig. 4B ). Width of expansion of first ventrite of male, on third ventrite, subequal to distance between clypeal teeth ( Fig. 6B ). Guyana , District 8: Mount Wokomung ( Fig. 10 , yellow square) ..................................................................... Deltochilum jocelynae sp. nov. – Head punctures on frons almost contiguous ( Fig. 2C ). Pronotal disc punctures separated by less than one diameter, almost contiguous ( Fig. 3C, G ). Pronotal disc with irregular shiny points ( Fig. 3G , white arrows). Punctures of third interstria on disc occupying about 1/10 th the distance between striae II and III ( Fig. 4C ). Width of expansion of first ventrite of male, on third ventrite, narrower than distance between clypeal teeth ( Fig. 6C ). Venezuela , Bolivar ( Fig. 10 , red star) ............................................................................................... Deltochilum nonstriatum sp. nov. 3. Elytral apical tubercles on interstriae III–VII ( Fig. 5A ). First stria almost twice wider than second stria ( Fig. 4A ). Striae III–VII subequal in width and conspicuous ( Fig. 4A ). Pronotal disc with shiny points well-defined and separated from punctures ( Fig. 3A ). Male metatrochanter with expansion on distal third. Width of expansion of first ventrite of male, on third ventrite, wider than distance between clypeal teeth ( Fig. 6A ). Sub-medial area of endophallus with elongate scales ( Fig. 8A , arrow). Guyana , District 8: Mount Wokomung ( Fig. 10 , blue circle) .................................................. Deltochilum gilli González-Alvarado & Vaz-de-Mello, 2021 – Elytral apical tubercles on interstriae III, V–VII ( Fig. 5D–E ). First stria subequal to slightly wider than second stria ( Fig. 4D–E ). Striae III–VII successively thinner and more ill-defined ( Fig. 4D– E ). Pronotal disc with shiny points irregular and contiguous to punctures ( Fig. 3D–E ). Male metatrochanter not modified. Width of expansion of first ventrite of male, on third ventrite, subequal to distance between clypeal teeth ( Fig. 6D–E ). Sub-medial area of endophallus with scales, but not elongate ( Fig. 8D–E ) Guyana , Mazaruni-Potaro District. Venezuela Bolívar ( Fig. 10 , white eightpoint star and green triangle) ............................................................................................................. 4 4. First stria wider than second stria ( Fig. 4D ). Punctures of third interstria on disc occupying about 1/10 th the distance between striae II and III ( Fig. 4D ). Pygidium with discal punctures occupying approximately 1/29 th the width on middle of pygidium and basal punctures almost contiguous ( Fig. 5D ). Guyana , Mazaruni-Potaro District: Takutu Mountains ( Fig. 10 , green triangle)....................................................................................... Deltochilum quasistriatum sp. nov. – First stria subequal in width to second stria ( Fig. 4E ). Punctures of third interstria on disc occupying about 1/14 th the distance between II and III ( Fig. 4E ). Pygidium with discal punctures occupying approximately 1/38 th the width on middle of pygidium basal punctures separated by less than one diameter but not almost contiguous ( Fig. 5E ). Venezuela , Bolívar : 10 km E of San Francisco ( Fig. 10 , white eight-point star) ................................................................. Deltochilum tenuistriatum sp. nov.