EXTREME DERMAL HYPOPIGMENTATION AND FULL-BODY TRANSPARENCY IN A LEAF-LITTER Craugastor FROG FROM A LOWLAND TROPICAL WET FOREST IN COSTA RICA

Charlyn Elizondo-Montano; Branko Hilje

doi:10.22201/fc.25942158e.2025.4.1458

Autores/as

Charlyn Elizondo-Montano Reserva Biológica Tirimbina, Puerto Viejo de Sarapiquí, Heredia, Costa Rica, 777-1000 San José, Costa Rica.
Branko Hilje Escuela de Ingeniería Forestal, Tecnológico de Costa Rica https://orcid.org/0000-0001-5701-5455

DOI:

https://doi.org/10.22201/fc.25942158e.2025.4.1458

Palabras clave:

Albinismo, cromatóforos, Craugastor fitzingeri, transparencia

Resumen

Las anomalías de pigmentación en anfibios son poco comunes, especialmente aquellas que implican la ausencia total de los tres tipos de cromatóforos. Reportamos un caso excepcional de hipopigmentación dérmica extrema en un juvenil presumiblemente de Craugastor fitzingeri, observado en la hojarasca del bosque lluvioso de la Reserva Biológica Tirimbina, Costa Rica. El ejemplar carecía por completo de pigmentación externa, presentando un cuerpo translúcido, órganos internos visibles y ojos sin pigmento aparente. Esta condición sugiere una combinación de albinismo congénito y deficiencia severa de cromatóforos (melanóforos, xantóforos e iridóforos). Fenotipos tan extremos son prácticamente inéditos en anfibios silvestres de desarrollo directo, como los del clado Terrarana. Este hallazgo aporta al limitado pero creciente conocimiento sobre anomalías congénitas de pigmentación en anfibios y subraya la necesidad de monitoreo continuo y estudios genéticos en individuos con fenotipos atípicos en ecosistemas tropicales.

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