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Fibropapillomatosis (FP) is a neoplastic disease affecting marine turtles around the tropics. Juvenile green sea turtles (Chelonia mydas) seem to be the most affected by the cutaneous tumors, which are not malignant but depending on their number, size, and location, can hamper survival. FP prevalence in sea turtles has increased over the past few decades in areas such as Espírito Santo (Brazil) and Texas (USA), but in Mexico few instances have been documented to date. Here we report a 12.2% FP prevalence in free-ranging turtles captured during 2017–2018 in the Veracruz Reef System National Park, a previously unreported site in Mexico, which is subject to environmental and anthropogenic pressures. Histopathological analysis of one tissue sample revealed tumors were consistent with the characteristics of fibropapillomas. They were not severe (0.01–7.16 cm), but the majority had a verrucous appearance and were mainly found on the flippers and eyes, being potentially detrimental to the health of juvenile turtles. We recommend continued monitoring of this population, and the information provided here can serve as a baseline for future studies in this area of the Gulf of Mexico, where FP had not been

La sirena menor (Siren intermedia) es registrada por primera vez en Tuxpan, por segunda vez en el estado de Veracruz y por tercera vez en México. Este hallazgo incrementa los puntos de distribución de la especie, previamente informada para Matamoros y Ciudad Victoria, Tamaulipas y Gutiérrez Zamora, Veracruz. Hasta donde se sabe, esta especie tiene una distribución disyunta en México.

El microhábitat de Chelonia mydas en el arrecife Cabezo, está compuesto por siete tipos de fondo arrecifal. Los parámetros oceanográficos registrados, consisten en aguas someras menores a 2.4 m de profundidad, temperatura del agua de 24.8 a 30.3 °C, concentraciones de oxígeno disuelto de 3.6 a 7.7 mg/L y salinidad de 25.4 a 38.1 ppt. La temperatura es el parámetro con variación significativa en relación al fondo arrecifal. La mayor abundancia de tortugas se distinguió en temporada de lluvias.

In oviparous tetrapods, the nesting-site selection by females is related to the habitat characteristics, which influences nest incubation temperature. Females can directly influence the incubation temperature by choosing certain construction materials or by building nests of different sizes. There are few studies focusing on these aspects in crocodilians that build mound nests. The aim of this study was to determine whether the nest size, its exposure to solar radiation, and the environmental temperature influence the incubation temperature of Morelet's crocodile (Crocodylus moreletii) nests. Artificial nests of two sizes (small and large) were constructed with similar characteristics to natural nests and placed in two locations differing in exposure to solar radiation (shaded and sunny). We used temperature and relative humidity data loggers to record the incubation temperature inside each nest every hour during the species' natural nesting period. Likewise, we recorded the ambient temperature every hour where the experiments were set up with temperature data loggers. We found that nest size and its exposure to solar radiation affected the incubation temperature, with smaller nests in shaded locations having lower incubation temperatures than larger nests in sunny locations. We discuss the importance of nest-site selection and maintenance behaviour of the mound nest by female crocodiles on the incubation temperature of the nest.

Lead and chromium contamination represents one of the most serious problems in the aquatic environments. The aim of this work was to develop and validate an accurate, sensitivity, and rapid method for the simultaneous determination of Pb and Cr at trace levels in tissues and fat of marine organisms such as turtle (Chelonia mydas), shark (Rhizoprionodon terraenovae), and dolphin (Tursiops truncatus), utilizing the total reflection X-Ray fluorescence (TXRF) spectroscopy. Working solutions were prepared in 10 mL of a solution 0.005 mol·L−1 EDTA and 1 mol·L−1 HNO3. In order to correct possible instrument drifts, 20 μg·L−1 of gallium was used as internal standard (IS). The results showed that TXRF method was linear over the concentration ranges of 5.242–100 μg·L−1 for Pb and 2.363–100 μg·L−1 for Cr. Limits of detection (LOD) achieved were 1.573 and 0.709 μg·L−1 for Pb and Cr, respectively, while limits of quantification achieved were 5.242 μg·L−1 for Pb and 2.363 μg·L−1 for Cr. The validated method was accurate and precise enough for determination of these heavy metals in samples of marine organisms as indicated by acceptable values of recovery between 90–101%. In addition, a certified reference material (BCR-279, sea lettuce) and a Centrum tablet were satisfactory analyzed, and the T-test for comparison of means revealed that there were no significant differences at the 95% confidence level between the values obtained with the proposed TXRF method and the certificated values. The repeatability of the method, expressed as relative standard deviation (RSD), was 5.1% and 4%, for Pb and Cr, respectively. In addition, other features of the developed method were a low sample volume of 10 μL, and the sample frequency achieved was 20 h−1.

Habitat perturbation due to human activities may generate numerous behavioural and physiological alterations in wild animals. In consequence, some individuals become more susceptible to diseases, while others modify their foraging behaviour or present a diminished reproductive success. In this study, we compare the daily activity pattern (DAP) and the levels of faecal glucocorticoids (fCORT) of individuals of spiny tailed iguana (Ctenosaura acanthura) found in conserved habitats, with those found in areas perturbed by human activities. Our results indicate that none of the behaviours (basking, resting, feeding, locomotion, movement and aggression) presented significant differences between habitats. Furthermore, the concentrations of fCORT were similar among individuals from both sites. We suggest that the spiny tailed iguana is a species that has adapted to perturbed areas, where it has found enough resources to survive. Our findings imply that iguanas are less sensitive to habitat degradation; additionally, these results may serve as a basis for future research aiming to describe behavioural and physiological characteristics of reptile species living in perturbed habitats.

ResumenSe presentan adiciones a la distribución geográfica y altitudinal de Lithobates johni, como nuevo registro para la herpetofauna del estado de Veracruz, México. La captura de ejemplares se realizó dentro de cuerpos de agua de la Reserva Ecológica Pancho Poza, Área Natural Protegida (ANP), situada en la zona montañosa central del estado. El estudio proporciona nuevos registros del intervalo de distribución altitudinal para esta especie en peligro de extinción, en más de 1 200m de su límite anterior. Asimismo, se amplía el intervalo conocido de distribución geográfica de la especie más de 50km al sur del registro más cercano (río Tehucante, Puebla).AbstractWe present additions to the geographical and altitudinal distribution of Lithobates johni, as a new record to the herpetofauna of the State of Veracruz, Mexico. Specimens were collected within river of Pancho Poza Ecological Reserve, a protected area located in the central highlands of the state. The study extends the altitudinal distribution range for this endangered species, more than 1 200m from its previous limit. Also the known geographical distribution range for the species extends more than 50km to the South of the nearest record (Tehucante River, Puebla).