A taxonomic monograph of the genus Tylodinus Champion (Coleoptera: Curculionidae: Cryptorhynchinae: Tylodina) of Chiapas, Mexico.

The species of the genus Tylodinus from the Mexican state of Chiapas are revised. We examined 989 specimens representing 36 species; 23 species are grouped into eight species groups with 13 species considered as Incertae sedis. A total of 32 species are described as new and one species is a new record for México. Species groups  (numbers of species in parentheses) and species are: Tylodinus buchanani species group (6) T. buchanani new species (type locality: Chiapas, Unión Juárez, Volcán Tacan), T. exiguus new species (type locality: Chiapas, Motozintla, 7 km SSW Motozintla de Mendoza), T. ixchel new species (type locality: Chiapas, Unión Juarez, Volcán Tacan), T. jonesi new species (type locality: Chiapas, Angel Albino Corzo, Reserva de la Biosfera el Triunfo, Campamento el Quetzal), T. variabilis new species (type locality: Chiapas, San Cristóbal de las Casas, Cerro Huitepec), T. wibmeri new species (type locality: Chiapas, Motozintla, 7 km SSW Motozintla de Mendoza); Tylodinus canaliculatus species group (3) T. canaliculatus Champion (Chiapas, Unión Juárez, Volcán Tacan, new record for  México), T. sepulturaensis new species (Type locality: Chiapas, Villa Corzo, Ejido Sierra Morena), T. triumforium new species (Type locality: Chiapas, La Concordia, 4 km SE Custepec); Tylodinus cavicrus species group (3) T. cavicrus Champion, T. pseudocavicrus new species (type locality: Chiapas, San Cristóbal de las Casas, Cerro Huitepec), T. rugosus new species (type locality: Chiapas, Villa Flores, Sierra Morena); Tylodinus coapillensis species group (2) T. coapillensis new species (type locality: Chiapas, Coapilla, ca. 10.5 km NE Coapilla), T. leoncortesi new species (type locality: Chiapas, Pueblo Nuevo Solistahuacán, La Yerbabuena); Tylodinus mutabilis species group (2) Tylodinus mutabilis new species (type locality: Chiapas, Villa Corzo, Ejido Sierra Morena), T. parvus new species (type locality: Chiapas, Trinitaria, Lagunas de Montebello); Tylodinus nodulosus species group (3) T. andersoni new species (Chiapas, Ángel Albino Corzo, Reserva El Triunfo, Polígono 1), T. nodulosus (Boheman), T. zilchi Kuschel; Tylodinus pusillus species group (2) T. porvenirensis new species (type locality: Chiapas, El Porvenir, El Porvenir (2 km NE)), T. pusillus new species (type locality: Chiapas, 4 km SE Custepec); Tylodinus spiniventris species group (2) T. lum new species (Chiapas, San Cristóbal de las Casas, Cerro Huitepec), and T. spiniventris new species (type locality: Chiapas, San Cristóbal de las Casas, Reserva Huitepec); Incertae sedis (13) T. pinguis new species (type locality: Chiapas, Ángel Albino Corzo, Reserva El Triunfo, Polígono 1) , T. kissingeri new species (type locality: Chiapas, Tapalapa, ca. 14 km NE Coapilla), T. complicatus new species (type locality: Chiapas, Pueblo Nuevo Solistahuacán, La Yerbabuena), T. dominicus new species (type locality: Chiapas, Villa Corzo, Reserva de la Biósfera La Sepultura), T. noctis new species (type locality: Chiapas, Coapilla, ca. 10.5 km NE Coapilla), T. rufus new species (type locality: Chiapas, San Cristóbal de las Casas, Cerro Huitepec); T. branstetteri new species (type locality: Chiapas, La Concordia, 4 km SE Custepec), T. kuscheli new species (type locality: Chiapas, Villa Flores, Ejido Sierra Morena), T. pappi new species (type locality: Chiapas, Unión Juárez, Volcán Tacan), T. gibbosus new species (type locality: Chiapas, Pueblo Nuevo Solistahuacán, Yerbabuena Reserve), T. immundus new species (type locality: Chiapas, San Cristóbal de las Casas Cerro Huitepec), T. intzin new species (type locality: Chiapas, Tenejapa, Yashanal), T. elongatus new species (type locality: Chiapas, Ángel Albino Corzo, Reserva El Triunfo, Polígono 1). Three species (T. nodulosus (Boheman), T. zilchi Kuschel and T. cavicrus Champion) are not known to occur in Chiapas but were included in this study to be more representative of inter- and intraspecific variation and to provide a better definition of the taxonomic limits of species and species groups.        Species groups are characterized and taxonomic composition and general distribution and ecological correlates summarized. Diagnoses and distributions are given for all species and ecological information is presented where available. Immature stages, life history and food habits are not known for any of the species.