The Brachypterous Species of Passalus (Pertinax) (Coleoptera: Passalidae), with the Description of a New Species from Sierra Nevada de Santa Marta, Colombia.

Brachypterism is a common condition cited in passalid beetles, mainly associated to species with strictly montane distributions. In the New World Passalids, brachypterism has been reported especially in the tribe Proculini, for which almost all genera have brachypterous species; meanwhile, in Passalini, the other Netropical tribe, it has been cited only for the genus Passalus, mainly in the subgenus Passalus (Passalus). Here we present a commented list of the brachypterous species of the subgenus Passalus (Pertinax); we redescribed Passalus gravelyi Moreira, P. quitensis (Kaup), P. striatissimus Luederwaldt, and P. sulcifrons (Kuwert) and describe a new species from Sierra Nevada de Santa Marta, Colombia.

Pseudacanthus alani, a New Species of Mesoamerican Bess Beetles (Coleoptera: Passalidae) of Oaxaca, Mexico and Nomenclatural Notes for the Genus.

A new species, Pseudacanthus alani n. sp., is described from cloud forest in Oaxaca, Mexico. This species is similar to Pseudacanthus junctistriatus Kuwert 1891 in size, shape of antennal lamella, and the absence of pubescence on abdominal terga, but has larger internal tubercles, an apex of central tubercle that is not free, glabrous elytral humerus, pubescent mesepisternum and mesepimeron and mesosternal scar, and male sexual characters. Photographs are provided of the head, male and female genitalia, and plectrum. Additionally, a taxonomic key to species of Pseudacanthus Kaup 1869 is provided, complemented with photographs of diagnostic characters. Finally, we propose two junior synonyms: Pseudacanthus solidus (Arrow 1907) n. syn. of Pseudacanthus junctistriatus and Pseudacanthus truquii Kuwert 1891 n. syn. of Pseudacanthus mexicanus (Truqui 1857).

Linear and geometric morphometric analyses of variation of the plectrum in four species of bess beetles, tribe Proculini (Coleoptera: Passalidae).

Bess beetles are sapro-xillophagous insects that inhabit decaying logs. They display sub-social behavior and acoustic communication. Adults produce sounds with an abdomino-alary stridulatory system. The sixth abdominal tergum has lateral protuberances with spines (pars stridens), whereas the hind wings have spines in the radial cell (plectrum). The potential taxonomic utility of these spines has not been studied. We evaluated the variation of spines in the plectrum of adult females sampling four species of Proculini using traditional and geometric morphometric methods. We divided the plectrum into five zones to compare the density, size and shape of spines among zones and among species comparing each zone separately. Spine shape and size were quantified with 2D cartesian coordinates and four variables from SEM micrographs. Separate univariate and multivariate analyses of variance revealed that the size, density and shape of spines is different among zones in each of the four species. Also, spine shape and size in all zones is different among species, which would imply that plectrum spines might have taxonomic utility. Additionally, disparity analyses showed that the peripheral zones have a higher variability, and the disparity values in the middle and apex zones are higher in the two species with a wide distribution range.

The Passalidae (Coleoptera, Scarabaeoidea) from Bolivia, with the descriptions of three new species.

Employing data from literature, examination of specimens in collections, and a field trip, a list of the species of Passalidae from Bolivia is elaborated. A total of 38 species is reported, including new records of Passalus inca Zang, 1905 and P. lunaris (Kaup, 1871), and three new brachypterous species: Passalus bolivianus sp. nov., P. canoi sp. nov., and P. gonzalezae sp. nov. Most of the species (27) belongs to the Passalini tribe, especially to the genus Passalus Fabricius, 1792 (19 species); the Proculini tribe is represented by eleven species in three genera. The number of species of Bolivia is low and reflects the lack of a systematic exploration of this country; more surveys are needed, especially in ecosystems such as montane forest and tropical rain forest.

ResumenEmpleando datos de literatura, el examen de especímenes en colecciones y recolectados en campo, elaboramos una lista de las especies de Passalidae de Bolivia. Registramos un total de 38 especies, incluidos los nuevos registros de Passalus inca Zang, 1905 y P. lunaris (Kaup, 1871), y tres nuevas especies braquípteras: Passalus bolivianus sp. nov., P. canoi sp. nov. y P. gonzalezae sp. nov. La mayoría de las especies (27) pertenecen a la tribu Passalini, especialmente al género Passalus Fabricius, 1792 (19 especies); la tribu Proculini está representada por 11 especies de tres géneros. El número de especies registradas para Bolivia es bajo y refleja la falta de una exploración sistemática de este país. Se necesitan más muestreos, especialmente en ecosistemas como el bosque montano y la selva tropical.

A New Species of Vindex Kaup (Coleoptera: Scarabaeoidea: Passalidae: Passalinae: Proculini) from Oaxaca, Mexico.

Vindex chimalapensis Ariza-Marín, Reyes-Castillo, Moctezuma & Sánchez-Huerta, a new species, is described from the cloud forest in Oaxaca, México. Vindex chimalapensis is like V. sculptilis Bates in the form of lateral elytral punctures and glabrous epipleura, but has dorsal punctures in the pronotum and the form of the aedeagus differs on the basal piece. Male genitalia, female genitalia, and head are shown in photographs. Vindex chimalapensis is the only species known from this genus with dorsal punctures on the pronotum. Ecology, distribution, and biogeography of Vindex and the Mountain Mesoamerican distribution pattern are discussed, with emphasis on V. chimalapensis.