Diversity and paleoenvironmental implications of an elasmobranch assemblage from the Oligocene-Miocene boundary of Ecuador

Investigating an Unknown Biodiversity: Evidence of Distinct Lineages of the Endemic Chola Guitarfish Pseudobatos percellens Walbaum, 1792 in the Western Atlantic Ocean

Anthropogenic actions have affected marine species for a long time, through overexploitation of natural stocks and habitat degradation, influencing the life strategies of several taxa, especially rays and sharks, which have suffered significant population declines in recent years. Therefore, conservation actions and stock management have become paramount. In this regard, chola guitarfish, Pseudobatos percellens, distributed throughout the Brazilian coast, is often commercially fished by local artisanal fleets or as by-catch in shrimp trawl fisheries. Therefore, this study aimed to understand the genetic diversity of P. percellens throughout the Brazilian coast, using single nucleotide polymorphisms (SNPs). Genetic analyses employing 3329 SNPs revealed a hidden biodiversity within P. percellens, with at least one lineage occurring in the Northern and Northeastern regions and another distributed in the Southeastern/Southern Brazilian coast, with high genetic differentiation between them. However, the Discriminant Analysis of Principal Components (DAPC) indicated the presence of in fact three lineages distributed in these regions that must still be better investigated. Therefore, to ensure adequate conservation of chola guitarfish biodiversity, populations must be managed separately along the Brazilian coast. Furthermore, the need for a taxonomic review for this group is noted.

Evaluation of a Paleontological Museum as Geosite and Base for Geotourism. A Case Study

The Santa Elena province in Ecuador has outstanding geological potential in petroleum, mining and geosite resources. All the wealth of palaeontological samples and their inherent link to the history of this territory require a recognised museum with educational and scientific material to support the potential and promotion of geotourism development. The Megatherium Palaeontological Museum is located in this province and was the first Palaeontological Museum in Ecuador. It exhibits samples corresponding to the Late Pleistocene Megafauna that inhabited the area. This study aims to evaluate the museum (a geoheritage element) as a possible (palaeontological) geosite by analysing its contributions to the geoheritage of the Santa Elena province. Thus, we also aim to enhance the geotourism of the area and promote its collections as a geotouristic attraction. The methodological process was based on: (i) information processing and systematisation in the museum and its environment; (ii) assessment of the museum’s geological interest through the method of the Geological Survey of Spain, the Brilha method and the Geosites Assessment Model; and (iii) a qualitative evaluation using the Delphi and the Strengths, Weaknesses, Opportunities and Threats methodologies to define strategies and proposals for museum development. Based on the results of the applied quantitative assessment, the museum has a “very high” (277/400) degree of geological interest, due to the high values of scientific (310/400), academic (310/400) and touristic (210/400) interest. In this same way, the results obtained through the Brilha method reflect a high scientific (290/400), educational (280/400), and tourist (315/400) interest and a low degradation risk (190/400) value in the museum. Furthermore, the applied Geosites Assessment Model shows the museum as a geosite with high main and additional values, placing it between the Z23 and Z33 fields of the global valuation matrix. The evaluation approached through Delphi analysis and Strengths, Weaknesses, Opportunities and Threats matrix allowed us to propose improvement strategies to take advantage of the museum resources as an alternative that strengthens the geotouristic development of the area.