Phylogenetics of Ogyges Kaup and the biogeography of Nuclear Central America (Coleoptera, Passalidae)

Geodispersal of the Typical Neotropical cenocron from South America to the Mexican Transition Zone: a cladistic biogeographical test

Analysis of the biotic assembly of the Mexican Transition Zone (MTZ) is challenging because of the convergence of taxa with different origins and biogeographical histories. The typical Neotropical cenocron corresponds to genera widespread in South America that might have dispersed to the MTZ in the Pliocene–Holocene. It has been exemplified with distributional patterns of several plant and animal taxa; however, their historical congruence has not been tested. We examined the historical relationships among the areas of endemism where Typical Neotropical taxa are found through a cladistic biogeographical analysis to determine whether they have dispersed simultaneously, showing a geodispersal pattern. We searched for Neotropical clades that dispersed to the MTZ from the Pliocene to the present. The distribution of nine animal clades in seven areas of endemism was analysed by cladistic biogeography. Redundant areas and widespread taxa were treated with paralogy-free and transparent methods. Patterns of area relationships were searched using a parsimony analysis of paralogy-free subtrees. The parsimony analysis found a single resolved tree showing a general pattern of area relationships: (Chacoan ((South Brazilian (Boreal Brazilian + Lesser Antilles)), (South American Pacific (Mesoamerican-Central America + Western Mexico)))). Distributional and phylogenetic information on the groups analysed contrast with a previous cladistic biogeographical analysis that has shown different area relationships, thus supporting the general hypothesis of a geodispersal event of the Typical Neotropical cenocron in the MTZ. Additionally, the analysis provided evidence of vicariant events related to the lifting of the Northern Andes and climatic changes during the Pleistocene.

The effect of landscape and human settlement on the genetic differentiation and presence of Paragonimus species in Mesoamerica

Foodborne diseases are a neglected research area, and despite the existence of many tools for diagnosis and genetic studies, very little is known about the effect of the landscape on the genetic diversity and presence of parasites. One of these foodborne disease is paragonimiasis, caused by trematodes of the genus Paragonimus, which is responsible for a high number of infections in humans and wild animals. The main Paragonimus sp reported in Mesoamerica is Paragonimus mexicanus, yet there are doubts about its correct identification as a unique species throughout the region. This, together with a lack of detailed knowledge about their ecology, evolution and differentiation, may complicate the implementation of control strategies across the Mesoamerican region. We had the goal of delimiting the species of P. mexicanus found throughout Mesoamerica and determining the effect of landscape and geology on the diversity and presence of the parasite. We found support for the delimitation of five genetic groups. The genetic differentiation among these groups was positively affected by elevation and the isolation of river basins, while the parasite's presence was affected negatively only by the presence of human settlements. These results suggest that areas with lower elevation, connected rivers basins, and an absence of human settlements have low genetic differentiation and high P. mexicanus presence, which may increase the risk of Paragonimus infection. These demonstrate the importance of accurate species delimitation and consideration of the effect of landscape on Paragonimus in the proposal of adequate control strategies. However, other landscape variables cannot be discarded, including temperature, rainfall regime, and spatial scale (local, landscape and regional). These additional variables were not explored here, and should be considered in future studies.

Current status of dung beetles (Coleoptera, Scarabaeidae, Scarabaeinae) diversity and conservation in Natural Protected Areas in Chiapas (Mexico)

Natural Protected Areas (NPAs) are consider adequate tools for biodiversity conservation. Currently in Mexico there are 182 federal NPAs classified according to their management objectives. Chiapas is the Mexican state with the highest number of decreed NPAs and also allocates one of the largest territorial extensions for its protection. Unlike other taxa, and despite their proven ability to respond to ecosystem changes, the study of dung beetles within Mexican NPAs has been underestimated, as they are not considered as a priority group within their management and conservation programs. Based on the review of information available in publications and database on dung beetles, a list of 112 species and seven subspecies recorded in 16 of the 19 federal NPAs established in Chiapas is presented. The species recorded by each NPA show a significant correlation with the number of publications, but a low percentage of them correspond to studies with systematic samplings and most of the species reported in several of the NPAs come from sporadic records, which prevents the study of several basic and applied aspects of dung beetles in the region. Therefore, studies that extensively analyze the communities of arthropod groups, such as the Scarabaeinae, are necessary to understand their response to changes in the ecosystem at local and regional scale. It is advisable that these insects be included in the previous justifying studies for the designation or establishment of NPAs and, in turn, considered in the biological monitoring programs of these areas for their capacity as a bioindicator group.

Tonantzin, a New Genus of Bess Beetle (Coleoptera, Passalidae) from a Montane Subtropical Forest in Central Mexico, with a Review of the Taxonomic Significance of the Mesofrontal Structure in Proculini

Mexico has the third highest diversity of passalid beetles in the World. Here we describe Tonantzinnew genus, a new monotypic genus, potentially endemic to the mountains of central Mexico. The new genus is diagnosed by a new configuration of characters from the mesofrontal structure (MFS) in addition to other characters. The MFS in Passalidae has been treated either as a composite complex character or a combination of individual characters. Using a broad taxonomic sample within Proculini, we discuss the taxonomic and systematic implications of the MFS for the tribe. We define the MFS type tepetl. Given the importance of the MFS for passalid taxonomy we propose a new delimitation of the structure using boundaries based on internal and external head structures. We argue that the treatment of the MFS as a complex character better captures the nature of this structure but we ultimately find a need to standardize the way in which this structure is described in the taxonomic literature and used in phylogenetic analyses.