The Canthon indigaceus species group represents a Typical Neotropical distributional pattern with wide penetration into the Mexican Transition Zone. This group consists of three species: C. (C.) indigaceus LeConte; C. (C.) chiapas Robinson; and C. (C.) chevrolati Harold. In this study, a new species for the group is described, C. (C.) cuixmala, collected along the tropical region of the Pacific coast and the Balsas River basin. The taxonomic status of members of the group were evaluated by comparing morphological characteristics and their biogeographic distributions. An updated dichotomous key is provided to separate members of this species group.

In this study, we revise the taxonomy of the endemic Mexican genus Ceratotrupes Jekel, 1865. It comprises three species, distributed in the Sierra Madre Occidental and Trans-Mexican Volcanic Belt (Ceratotrupes fronticornis (Erichson, 1847) and Ceratotrupes bolivari Halffter & Martínez, 1962), and the Sierra Madre del Sur (Ceratotrupes sturmi (Jekel, 1865)). We confirm C. mniszechi (Jekel, 1865) as a junior subjective synonym of C. sturmi. The examination of the holotype of C. sturmi and specimens recently collected in the Sierra Sur de Oaxaca (Oaxaca) and Omiltemi (Guerrero) allowed us to identify and describe a new species, Ceratotrupes gonzaloi sp. nov. from Omiltemi, Guerrero. We redescribe the morphology of C. sturmi and provide a diagnostic key to the four members of the genus Ceratotrupes. Photographs of the habitus and male genitalia of the four species, a distribution map, and observations on their ecology and biogeography are provided.

TheOnthophagus anthracinusHarold, 1873 (Coleoptera: Scarabaeidae: Scarabaeinae: Onthophagini) species complex of theOnthophagus landoltiHarold, 1880 species group is established and analysed. Anew species,O. etlaensis, is described from this group.Onthophagus mextexusHowden and Cartwright, 1970 is considered a valid species andO. knulliHowden and Cartwright, 1963 is placed in synonymy withO. durangoensisBalthasar, 1939new synonymy. A key for theO. anthracinusspecies complex is presented along with photographs and illustrations of the main taxonomic differences. An update of theO.landoltispecies group is presented.

La investigación en biodiversidad y conservación en México ha avanzado en gran medida porque están vinculadas a la existencia de estaciones biológicas, reservas de la biosfera o áreas naturales protegidas. El Centro de Investigaciones Costeras La Mancha (CICOLMA) es una de las estaciones pioneras del país en la investigación de ecosistemas costeros, sin embargo, los estudios sobre la fauna de escarabajos en esta área han sido mínimos. El objetivo del presente trabajo fue documentar la fauna de Scarabaeoidea presente en el CICOLMA de abril de 2003 a marzo de 2004, donde se realizaron colectas de escarabajos con técnicas directas e indirectas. Se obtuvo una muestra de 865 individuos de Coleoptera, Scarabaeoidea, de las familias Cetoniidae, Melolonthidae, Passalidae, Scarabaeidae y Trogidae, que representan 66 especies de 41 géneros. Las especies Cotinis pauperula Burmeister, 1847, Euetheola bidentata (Burmeister, 1847), Paranomala flavilla (Bates, 1888) y Pelidnota virescens Burmeister, 1844, representan nuevos registros para el estado de Veracruz. Se incluye una clave dicotómica para separar las especies de Scarabaeoidea de la región y datos sobre su fenología.