A taxonomic review of the endemic Mexican genus Ceratotrupes Jekel, 1865 (Coleoptera: Geotrupidae: Ceratotrupini), with the description of an unexpected new species from the Sierra Madre del Sur Author Arriaga-Jiménez, Alfonsina C63A2853-E857-4683-A5AE-626D2387A352 Insect Ecology Lab, School of Environmental and Rural Sciences, University of New England, Armidale NSW 2351, Australia. aarriaga@une.edu.au Author Zunino, Mario A1EE6CAE-8FC5-413B-9984-625DF6C4C486 Instituto de Ecología A. C., Invited researcher, Carretera antigua a Coatepec 351, Xalapa 91070, Veracruz, Mexico. mariozunino@hotmail.it Author Halffter, Gonzalo CF2EF74E-878A-4BC8-82A2-01F669049650 Deceased 11 March 2022. Former address: Aldama Street 17, Centro, 91500 Coatepec, Veracruz, Mexico. Author Escobar-Hernández, Fernando 0F5EFB92-6896-4E9D-A3E3-6DB3F33B762A Red de Ecoetología, Instituto de Ecología, INECOL A. C. Xalapa, México, Carretera antigua a Coatepec 351, El Haya, Xalapa 91070, Veracruz, Mexico. fernando.escobar@inecol.mx Author Rossini, Michele 2698881E-C265-42DB-8A8E-0BE3A5BDDB97 Finnish Museum of Natural History (LUOMUS), University of Helsinki, Pohjoinen Rautatiekatu 13, Helsinki, 00014, Finland. & Department of Agronomy, Food, Natural resources, Animals and Environment (DAFNAE), University of Padova, Via dell'Università 16, 35020, Legnaro (PD), Italy. text European Journal of Taxonomy 2023 2023-07-24 885 1 20 journal article 57492 10.5852/ejt.2023.885.2183 f1935cd8-83c6-45fd-aac5-8c6659a934aa 2118-9773 8177540 A928AB6A-0029-4CEA-B941-C2238643835A Identification key to the species of the genus Ceratotrupes Jekel, 1865 1. Anterior half of lateral edges of pronotum curved ........................................................................... 2 – Anterior half of lateral edges of pronotum straight and convergent ................................................. 3 2. Anterior angles of pronotum of male evenly curved; outer surface of the first antennomere of antennal club with a deep elliptical groove ( Fig. 2C ); middle and posterior trochanters densely and clearly punctate ....................................................................... C. bolivari Halffter & Martínez, 1962 – Anterior angles of pronotum of male obtusely squared; outer surface of the first antennomer of antennal club either without or with a feeble groove; middle and posterior trochanters with scattered punctures ......................................................................................... C. fronticornis ( Erichson, 1847 ) 3. Posteromedial edge of pronotum without margin ( Fig. 4C ); clypeal horn strong, as large as one third the distance between inner margin of eyes, tip medially depressed ( Fig. 4A, C ); anteromedial pronotal projection with parallel sides ( Fig. 4A, D ), apically almost as large as half the distance between inner margin of eyes, apical edge widely depressed, with lateral protrusions distant; elytral interstriae very finely and densely punctate ........................................................ C. gonzaloi sp. nov. – Posteromedial edge of pronotum margined ( Fig. 3C ); clypeal horn thin, as large as one fifth of the distance between inner margin of eyes, tip medially not depressed, narrow and blunt ( Fig. 3A, C ); anteromedial pronotal projection with convergent sides, apically almost as large as one third of the distance between inner margin of eyes, apical edge very narrowly depressed, with lateral protrusions very close; elytral interstriae unpunctured ................................... C. sturmi ( Jekel 1865 )