A taxonomic revision of the New World genus Agamopus Bates, 1887 (Coleoptera: Scarabaeinae: Ateuchini) Author Costa-Silva, Vinícius 5B21A1A6-7EAE-42F0-878B-509040B92860 Laboratório de Entomologia Integrativa, Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Campinas, São Paulo, Brazil. & Laboratório de Scarabaeoidologia, Instituto de Biociências, Universidade Federal de Mato Grosso (UFMT), Cuiabá, Mato Grosso, Brazil. silvavinicius92@gmail.com Author Carvalho, Edrielly 2FE6FEAB-81AB-41CB-B9B7-A0D3563CF68F Laboratório de Scarabaeoidologia, Instituto de Biociências, Universidade Federal de Mato Grosso (UFMT), Cuiabá, Mato Grosso, Brazil. & Instituto Nacional de Pesquisas da Amazônia (INPA), Av. André Araújo, 2936, Petrópolis, CEP 69067 - 375, Manaus, Amazonas, Brazil. edrielly.carol@gmail.com Author Vaz-De, Fernando Z. 2FF2B7D6-1A6B-43C1-9966-A1A949FB2B05 Laboratório de Scarabaeoidologia, Instituto de Biociências, Universidade Federal de Mato Grosso (UFMT), Cuiabá, Mato Grosso, Brazil. vazdemello@gmail.com text European Journal of Taxonomy 2022 2022-03-23 806 1 64 89 http://zoobank.org/d0442f62-6e6d-47df-affe-443472343037 journal article 20110 10.5852/ejt.2022.806.1703 98d2d2bb-4ecc-4591-a4a9-8dd9cc12d870 2118-9773 6384533 D0442F62-6E6D-47DF-AFFE-443472343037 Agamopus joker sp. nov. urn:lsid:zoobank.org:act: 81A805C8-E8AD-4224-88C1-B0A1256E9A0D Figs 3–4 , 5B Differential diagnosis Agamopus joker sp. nov. shares with A. viridis the presence of two small tubercles on the head ( Fig. 5B – white arrows). However, the two species can easily be distinguished by the shape of the pygidial sulcus, which is arched in A . viridis (and other Agamopus species – as in Fig. 9E ), but sinuous in A . joker ( Fig. 4D ). Furthermore, the inner edge of the metatibia is noticeably curved and strongly crenulate in A. joker , being unique among representatives of the genus ( Fig. 4C ). Also, A. joker has the apex of the parameres abruptly curved downwards and flattened dorso-ventrally ( Fig. 4E ), differing from other species of Agamopus . Etymology The specific name ‘ joker ’, an English proper noun in the nominative case used in apposition, is an eponym after the homonymous supervillain from the DC Comics Universe. It is a reference to the sinuous pygidial sulcus of this species, which resembles the shape of a smiley clown’s mouth. Fig. 3. Geographical distribution map of Agamopus joker sp. nov. (blue circle); A . unguicularis ( Harold, 1883 ) (green circles); and A . castaneus Balthasar, 1938 (red circles). Type material Holotype BRAZIL • ♂ ; first label [aged white, unknown handwriting]: “2 – 49 [vertical] / P. Grossa / Lageado.”; second label [aged white, unknown handwriting]: “5211 [vertical] / Agamopus / viridis / Bouc.”; third label [aged white, Pereira's handwriting]: " Agamopus / viridis 5211 / Bouc. / P. Pereira det. [typeset] 99 [Pereira's handwriting]"; fourth label [red with black border, printed]: Agamopus joker ♂ / Costa-Silva et al., 2022 / HOLOTYPE"; CEMT ( Fig. 4G ). Holotype description Habitus as in Figs 4A‒B . Colour: dark brown, metallic. Oblong body. Length: 5.6 mm (excluding head). Width: 3.8 mm . HEAD. Hemispheric. Surface with dense punctation; anterior half foveolate-puncticulate and with erect yellow setae. Clypeal margin and lateral margin of head with yellow setae projecting from underneath. Two triangular clypeal teeth, separation between teeth V-shaped. Lateral clypeal carina well-defined and Fig. 4. Agamopus joker sp. nov. Holotype, ♂ (CEMT). A . Habitus, dorsal view. B . Habitus, ventral view (black arrow indicating the longitudinal keel slightly marked). C . Hind tibia (black arrow indicating the elongate apical process in the metatibia). D . Sulcus in the pygidium. E . Aedeagus, lateral view (black arrow indicating the gibbosity near base). F . Aedeagus, dorsal view. G . Labels. Scale bars = 1 mm. oblique (as in Fig. 5B – red arrows), ending in small tubercle on each side. Antennae yellow; antennal club covered by small golden bristles. PRONOTUM. Dark brown, metallic, shiny. Wider ( 3.18 mm ) than long ( 1.7 mm ); delimited by carina around. Surface covered by dense and homogeneous punctation ( Figs 4A and 5B ). Anterior angles rounded, pointed forward. Lateral margin smooth; rounded. Hypomeron with surface subtly rugose and densely punctate; anterior half deeply excavated, separated from posterior half by well-defined carina; posterior half with a longitudinal keel slightly marked, parallel with lateral margin ( Fig. 4B – black arrow). MESOVENTRITE. Trapezoidal; anterior margin wider than posterior. Surface fully punctated. Mesometasternal suture straight. METAVENTRITE. Fully punctated. Punctures larger and well-marked between mesocoxae; punctures slightly smaller in the posteromedial region ( Fig. 4B ). ELYTRA. Suboval. Lateral margins slightly angled. Seven striae well-defined; punctation equidistant on each stria. Surface of interstriae covered by micropunctation. LEGS. All fully covered by punctation. Protibiae slightly curved; three main teeth on outer edge and subtly crenulated to the base; inner apical angle of protibiae ~ 90°; ventral surface with longitudinal carina from base to apex. Meso- and metafemora with posterior edge smooth. Mesotibiae gradually widened apically; apical width approximately 1/4 of total length. Metatibiae visibly arched; inner edge crenulate with yellow setae ( Fig. 4C ); parallel margins in the anterior half, expanding slightly in the posterior half. Inner margin with a projection beyond apex, near to the spur. First to fourth protarsomeres almost rounded; 5 th tarsomere elongate, longer than first three tarsomeres culminated; apex truncate. Meso- and metatarsomeres equal in shape and length; first to third tarsomeres with dense ventral yellow setae. Tarsal claws falciform; longer than first tarsomere ( Fig. 4A–C ). Fig. 5. Cephalic integument of species of Agamopus Bates, 1887 . A . A. lampros Bates, 1887 (CEMT): smooth and lacking tubercles. B . A . joker sp. nov. , holotype, ♂ (CEMT), with dense punctuation and two small tubercles. White arrows indicating the small cephalic tubercles. Red arrows indicating the lateral clypeal carina. Scale bars = 1 mm. ABDOMEN. Six ventrites; each ventrite with row of punctation in the anterior margin; sides with sparse punctation. Lateral part of each ventrite longer than in the middle. Sixth ventrite completely covered by well-marked punctation. PYGIDIUM. Wider than long; glabrous, covered by micropunctation. Deep transverse and sinuous sulcus in centre of disc ( Fig. 4D ). MALE GENITALIA. Lateral view: parameres symmetrical; phallobase with dorsal gibbosity near base ( Fig. 4E – black arrow); distal portion of parameres abruptly curved downwards ( Fig. 4E ). Dorsal view: tips of parameres trapezoidal, expanded laterally, pointed ( Fig. 4F ). Female Unknown. Geographic distribution The species is only known from type locality, Ponta Grossa, Paraná , Brazil ( Fig. 3 ).