Reporting on a half-blind Cane toad Rhinella marina (Anura: Bufonidae) from the island of Montserrat

Abstract

Reportamos sobre un individuo adulto de sapo de caña (Rhinella marina) con anoftalmía en la isla de Montserrat. El individuo, con el globo ocular derecho ausente, también presentaba lesiones en la parte superior de su cabeza, probablemente como resultado de intentos fallados de depredación por parte de roedores invasores en la isla. Aunque esta pueda ser la explicación más probable para el párpado hundido, registros previos de una prevalencia anormal de ojos ausente en poblaciones introducidas de Rhinella en islas pequeñas pueden sugerir la aparición de un patrón que valga la pena investigar.

Ocular abnormalities in two sympatric salamanders (Caudata: Plethodontidae) in a pine-oak forest of La Malinche National Park, Mexico

“…Abnormalities are permanent structural defects caused by errors in the morphogenesis of organisms due to genetic factors (flawed genes), epigenetic factors (e.g., contamination, poor nutrition), and physical trauma (Lannoo 2008, Sánchez-Domene et al 2018, Ferreira et al 2019. Abnormalities have been described in various structures (e.g., the spine, limbs, toes and fingers, head, jaw, skin color, and eyes), and each one arises during different periods of development; for example, in the embryonic period, prior to or during metamorphosis (Sánchez-Domene et al 2018).…”

“…In amphibians, most cases of malformations have been primarily documented in anurans (Lannoo 2008, Ferreira et al 2019, Bosch et al 2021, Venerozo-Tlazalo et al 2022; nevertheless, this could be related to the fact that salamanders and caecilians exhibit more cryptic habits that make them less detectable (Davic and Welsh Jr. 2004, Gower et al 2004, Müller et al 2020, Cante-Bazán 2022. In Mexico, the documentation of malformations in salamanders is scarce in comparison to anurans (Cruz-Pérez et al 2009, Soto-Rojas et al 2017, Venerozo-Tlazalo et al 2022, and the malformations most frequently observed are associated with frog limbs (Aguillón-Gutiérrez and Ramírez-Bautista 2015, Monroy-Vilchis et al 2015, Domínguez-Moreno et al 2018, Carmona-Zamora et al 2020, Reyes-Servín and Díaz-García 2023.…”

“…Additionally, there is the diffi culty of identifying the potential agents responsible for the abnormalities in the fi eld. In this regard, some authors suggest that this type of abnormalities could arise due to natural mutation rates (Sánchez-Domene et al 2018) or as a result of failed predation attempts (Ferreira et al 2019).…”