1. The Neotropical otter Lontra longicaudis is a widespread semiaquatic carnivore living in a wide variety of environments in both fresh-water and salt-water ecosystems. We summarise the current knowledge on distribution, ecology, behaviour, evolution and conservation status of the species, and highlight the main threats that have been affecting it as well as priority actions for securing its survival. 2. The current geographical range of Lontra longicaudis is discussed, as well as several efforts that have been made to update knowledge of the range. Throughout its known distribution area, the Neotropical otter has high genetic diversity, and recent molecular research suggests that variations in genetic diversity are related to geography. Taxonomic issues regarding the existence of subspecies persist, mainly due to limited sampling in key portions of the species' range. 3. Although the Neotropical otter is widely distributed in Latin America and has flexible behaviour, it is subjected to a variety of threats, which lead this otter to be officially considered Threatened in several countries within its geographical range. 4. The species still faces an uncertain future due to the impact of human activities, thus justifying its classification as Near Threatened in the International Union for Conservation of Nature's Red List. The real level of human-otter conflicts and the impact of modified environments on Neotropical otter populations are still unclear, and must be a priority focus of future studies. 5. There is an urgent need to increase our knowledge on aspects of the Neotropical otter's biology, such as reproduction, generation time, behaviour, physiology, distribution limits, sanitary aspects, evolution and taxonomy. Understanding these topics is vital to ensure the long-term survival of the species, both at the local and at the regional scale, as well as to provide the basis for environmental education actions involving local riverside human communities.

We studied some ecological aspects of the neotropical Otter on the La Veleta dirt road located in the intensive use area of the Flora and Fauna Protection Area (Área de Protección de Flora y Fauna) "Laguna de Terminos". We conducted this study from March to December of 2007, it consisted on the search and identification of otter traces in a dirt road and channels in the zone. A total of 120 km were covered, and 104 traces were found (35 tracks, 16 sunning places, 29 scats, 16 latrines and 8 direct observations). We estimated a mean relative abundance of 0.86 ± 0.472 tracks/km. Temporarily the highest abundance was obtained during the Northern winds season (1.12 ± 0.288 tracks/ km) and the lowest abundance was recorded during the dry season (0.70 ± 0.242 tracks/ km). In addition to the 29 stools collected along the transects, we collected another 77 in nearby areas for a total of 106 stools. Fish (54.7%) was the highest consumption group, followed by crustaceans (20.5%), mollusks (14.8%), reptiles (5.1%) and insects (4.9%). No significant differences were found in the frequency of consumption of prey groups per season (X 2 = 5267, df = 4, P < 0.261). Results suggest that otters are permanently in the area and that environmental changes on the area, exerts some influence in their abundance, diet and seasonal movements. It is recommended that the vegetation cover in the study area are protected, and the prevention of pollution in the water bodies.

Resumen El murciélago pálido tropical (Bauerus dubiaquercus) es una especie poco conocida. Existe escasa información sobre su distribución en México, encontrándose sólo registros esporádicos en los estados de Campeche, Guerrero, Nayarit, Quintana Roo y Veracruz. En septiembre de 2017 se capturó y fotografió un ejemplar de B. dubiaquercus en el ejido Niños Héroes, municipio de Tenosique de Pino Suarez, Tabasco, México. Éste se localiza dentro del área natural protegida Cañón del Usumacinta y representa el primer registro documentado de la especie en Tabasco y el más reciente en la región sureste de México, lo que contribuye al conocimiento de la especie. Palabras clave: Área Natural Protegida, Chiroptera, selva mediana perennifolia, Vespertilionidae AbstractThe southern desert bat (Bauerus dubiaquercus) it’s a little known species. There is little information about its distribution in Mexico, with sporadic records in the states of Campeche, Guerrero, Nayarit, Quintana Roo and Veracruz. In September 2017, an individual of B. dubiaquercus was captured and photographed in the Ejido Niños Héroes, municipality of Tenosique de Pino Suarez, Tabasco, Mexico. This is located within the protected natural area Cañon del Usumacinta and represents the first documented record in Tabasco of the species and the most recent in the southeast region of Mexico, thus contributing to the knowledge of the species. Key words: Chiroptera, medium evergreen forest, natural protected area, Vespertilionidae