Anomalías en la región sacra de Caiman yacare (Daudin, 1802) (Crocodylia: Alligatoridae) de Corrientes, Argentina.

Guillermo Agustín Escobar; Víctor Hugo Zaracho; Carlos Alberto Luna

doi:10.30972/fac.3618893

Authors

Guillermo Agustín Escobar Laboratorio de Ecología de Aves-ILPLA (CONICET-UNLP) https://orcid.org/0009-0002-3761-2556
Víctor Hugo Zaracho Laboratorio de Herpetología, Facultad de Ciencias Exactas y Naturales y Agrimensura (UNNE), https://orcid.org/0000-0002-0790-2432
Carlos Alberto Luna Instituto de Antropología de Córdoba (IDACOR, CONICET-UNC) https://orcid.org/0000-0002-6574-4874

DOI:

https://doi.org/10.30972/fac.3618893

Keywords:

reptiles, Caimaninae, yacare, bone malformation, Hox genes

Abstract

Morphological anomalies recorded in wild reptiles are scarce compared to those in captive animals, and are usually detected in post-mortem examinations. This note describes new skeletal anomalies observed in the sacral region of wild specimens of Caiman yacare. Caudal hemisacralization and an ectopic condyle were identified. Although it was not possible to establish a cause-effect relationship, possible genetic and teratological explanations are explored based on previous reports in other crocodilians. This contribution highlights the importance of reporting morphological anomalies found in reptiles, which could indicate environmental disturbances.

Downloads

Download data is not yet available.

References

Brunell, A. M., Rainwater, T. R., Sievering, M. y Platt, S. G. (2015). A new record for the maximum length of the American alligator. Southeastern Naturalist, 14(3), 38-43. https://doi.org/10.1656/058.014.0302

Campos, Z., Llobet, A., Magnusson, W.E. y Piña, C. (2020). Caiman yacare. The IUCN Red List of Threatened Species, Artículo e.T46586A3009881

Christ, B., Huang, R. y Scaal, M. (2007). Amniote somite derivatives. Developmental dynamics: an official publication of the American Association of Anatomists, 236(9), 2382-2396. https://doi.org/10.1002/dvdy.21189

Escobar, G. A., Zaracho, V. H., Monferran, M. D., Luna, C. A. y Cuaranta P. (2025). Comprehensive postcranial osteology of the black yacare, Caiman yacare (Alligatoridae: Caimaninae): detailed descriptions, illustrations, and comparison across Crocodylia. Zoological Journal of the Linnean Society, 205(4), zlaf168. https://doi.org/10.1093/zoolinnean/zlaf168

Garcês, A., Pires, I. y Rodrigues, P. (2019). Teratological effects of pesticides in vertebrates: a review. Journal of Environmental Science and Health, Part B, 55(1), 75–89. https://doi.org/10.1080/03601234.2019.1660562

Griffin, C. T., Stefanic, C. M., Parker, W. G., Hungerbühler, A. y Stocker, M. R. (2017). Sacral anatomy of the phytosaur Smilosuchus adamanensis, with implications for pelvic girdle evolution among Archosauriformes. Journal of Anatomy, 231(6), 886-905. https://doi.org/10.1111/joa.12681

Horváth, G. (2025). Spinal deformities in wild reptiles: a systematic review and meta-analysis. Biology, 14(9), 11-19. https://doi.org/10.3390/biology14091119

Iungman J., Piña, C. I. y Siroski, P. (2008). Embryological development of Caiman latirostris (Crocodylia: Alligatoridae). Genesis, 46, 401–417. https://doi.org/10.1002/dvg.20413

Larriera, A. e Imhof, A. (2006). Proyecto Yacaré. En: Bolkovic, M. L. y Ramadori, D. (Eds.), Manejo de Fauna Silvestre en la Argentina-Programas de uso sustentable (1ra ed, pp. 51-64). Ministerio de Salud y Ambiente de la Nación.

LePore, C. N., y McLain, M. A. (2024). Variation in the sacrum of phytosaurs: New evidence from a partial skeleton of Machaeroprosopus mccauleyi. Journal of Anatomy, 244(6), 959-976. https://doi.org/10.1111/joa.14007

Poletta, G. L., Larriera, A., Kleinsorge, E. C. y Mudry, M. D. (2009). Genotoxicity of the herbicide formulation Roundup® (glyphosate) in broad-snouted caiman (Caiman latirostris) evidenced by the Comet assay and the Micronucleus test. Mutation Research, 672(2), 95-102. https://doi.org/10.1016/j.mrgentox.2008.10.007

Poletta, G. L. (2011). Monitoreo de daño inducido por plaguicidas en Caiman latirostris (Yacaré overo) como organismo centinela de los humedales de Argentina. [Tesis de doctorado. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales]. Biblioteca Digital Exactas. https://bibliotecadigital.exactas.uba.ar/collection/tesis/document/tesis_n4854_Poletta

Salisbury, S. W. y Frey, E. (2001). A biomechanical transformation model for the evolution of semi-spheroidal articulations between adjoining vertebral bodies in crocodilians. En G. C. Grigg, F. Seebacher y C. E. Franklink (Eds.), Crocodilian biology and evolution, (pp. 121-148). Surrey Beatty & Sons.

Scheyer, T. M., Hutchinson, J. R., Strauss, O., Delfino, M., Carrillo-Briceno, J. D., Sánchez, R. y Sánchez-Villagra, M. R. (2019). Giant extinct caiman breaks constraint on the axial skeleton of extant crocodylians. Elife, 8. https://doi.org/10.7554/eLife.49972

Serrano, O. S., Garcês, A., Pires, I., Calderón Mateus, J. A., Olivera, J. M. y Dávila, J. J. (2024). Congenital anomalies in American crocodile (Crocodylus acutus, Cuvier, 1807) embryos from a farm breeder in Colombia. Veterinary Sciences, 11(7), 317. https://doi.org/10.3390/vetsci11070317

Wassersug, R. J. (1976). A procedure for differential staining of cartilage and bone in whole formalin-fixed vertebrates. Stain technology, 51(2), 131-134. https://doi.org/10.3109/10520297609116684