Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

Abstract: Phenotypic variation in the sea urchin Eucidaris tribuloides (Cidaroida: Cidaridae) along the Corridor of the Southwestern Gulf of Mexico. The intraspecific morphological variation can be attributed to the result of the genetic variation or the influence of environmental heterogeneity. In the latter case, the organisms are exposed to diverse environmental conditions which have an influence on their biological processes and can be seen reflected in the morphological adaptations of the species. Indeed, the Reef Corridor of the Southwest Gulf of Mexico (CASGM, in its Spanish acronym) is constituted of geographically separated reefs that are exposed to different large-scale oceanographic factors and show their own attributes with multiple environmental variables. Therefore, this can stimulate the morphological variations of the populations of the species that are distributed in this corridor. The aim of this study was to determine the morphological variation of the Aristotle’s lantern of the sea urchin Eucidaris tribuloides along the CASGM. It was analyzed the allometric relation between the height of the Aristotle’s lantern and the diameter of the test of 104 specimens, we also used a covariance analysis to detect allometric differences between group. Apart from that, the variation of the shape of a rotule and a demi-pyramide for each sea urchin were analyzed using geometric morphometry. The results of this present study showed allometric differences among the reef systems in the north, center and south of Veracruz. The shape of the rotula and demi-pyramid of sea urchins of the north zone are different from the central and south area. However, there were no differences in shape between the center and the south area. The centroid size of the rotula and demi-pyramid of the sea urchins of the north are larger than those in the center and south. These results can be explained mainly by the geographical and environmental gradients of the CASGM, in addition to the feeding habits of E. tribuloides and the availability of the food resource in the habitat where they are established. As a stimulus to the morphological variation found in this research is also considered the distance among the reef systems and the marine currents patterns.

Introducción: La administración de de un agonista de un fármaco alfa- 2-adrenérgicos asociada con la técnica del cateterismo uretral , es un método de desarrollo reciente en la colección seminal en felinos, ofreciendo las ventajas   sobre la colecta por electroeyaculación y la colecta epididimária. La técnica se ha probado en   Panthera   onca   y felinos de pequeño porte. Métodos: En este estudio se utilizaron individuos de   Panthera   onca   ,   Puma  yagouaroundi  y Leopardus   wedii   en cautiverio en el parque   Zoobotánico Getúlio Vargas, Salvador, Bahia, Brasil. Fue utilizado los farmácos de clorhidrato de medetomidina (0,1mg /kg) y cetamina (5mg /kg) y fue colectado semen por medio del cateterismo uretral. Durante el desarrollo del procedimiento, se realizó la colecta de los datos biométricos corporales y testiculares, así como la ultrasonografáa de los testículos. Las muestras seminales frescas fueron evaluadas los parámetros de volumen, por microscopía convencional, el vigor espermático, motilidad total,  motilidad progresiva,  la integridad estructural y funcional de la membrana plasmática y la morfología espermática. Las muestras se sometieron a un proceso de congelación   -   descongelación   utilizando tres diferentes crioprotectores.   Las muestras descongeladas fueron evaluadas por  microscopía convencional, análisis seminal computarizado y  citometría   de flujo. Resultados: En este estudio fue realizado con éxito la técnica de colección seminal en las tres especies, siendo el primer estudio que informa de los parámetros seminales  de P. yagouaroundi y el primero que reporta la colección seminal uretral en   L.   wiedii. Los datos presentados describen la   morfocinética   espermática de las especies incluidas de forma pionera. No hubo diferencias (P>0,05) en la calidad seminal evaluando por grupo de crioprotector, ni diferencias en la integridad de las membranas pré e   post-congelamento. Discusión: Foi posible solamente la comparación con otras técnicas de colección seminal o con resultados de calidad seminal obtenidos de muestras de  gato doméstico. El establecimiento de una potencial asociación de las características físicas del animal y la calidad seminal, es información de suma importancia en la aplicabilidad para la elección de reproductores en los programas de reproducción asistida.

We explain through potential distributions and changes in altitudinal variation, the possible impacts of climate change in an endangered micro-endemic rodent of Mexico with narrow altitudinal range, Heteromys nelsoni and a rodent with a wide distributional and altitudinal range, Heteromys goldmani. We obtained historical and current records of both Heteromys species. Potential distribution models were generated using Maxent, including altitudes for each species and bioclimatic layers. We determined the Extent of Occurrence and Area of Occupancy for H. nelsoni according to the criteria of the IUCN in order to generate information about its risk status. The altitude is not a variable that determines a shift in the distribution caused by climate change. In contrast, the temperature and precipitation are important for the potential distribution of both Heteromys species. The future changes in climatic conditions will reduce the area of suitable habitat for H. nelsoni and will favor the presence of H. goldmani. The distribution surface is not greater than 33.44 km2 for H. nelsoni. Therefore, is urgent to re-evaluate their conservation status by the IUCN, mainly in its B criterion, and to take specific actions for their conservation. We suggest the creation of a terrestrial protected area.