Ontogenetic and interelemental study of appendicular bones of Caiman latirostris Daudin, 1802 sheds light on osteohistological variability in crocodylians

PEREYRA, MARIA E.; BONA P.; SIROSKY, P.; CHINSAMY, A.

Journal of Morphology

John Wiley and Sons Inc

Año: 2024 vol. 285

The osteohistology of vertebrates provides a reliable source to deduce biological information, particularly regarding growth and development. Although osteohistological studies in Neosuchia (Crocodyliformes, Mesoeucrocodylia) are relatively numerous, the number of species studied within the group is still small. Extant crocodilians are known to exhibit intraspecific variability linked to environmental conditions, habitat, feeding, and other intrapopulation factors. Here, we analyzed theosteohistology of the living South American Caiman latirostris throughout posthatching ontogeny. The histology of several appendicular bones of 13 different‐ sized captive and wild individuals were examined. Although some thin sections revealed the classic lamellar, parallel‐fibered, or woven bone matrices, others showed a variation and a mix between the organization of the bone tissue. These histological differences are likely related to variability in the growth dynamics of caimans. In some bones of the juveniles studied, remnants of embryonic bone were observed. Osteohistological variation related to prevailing environmental conditionsis documented. Furthermore, our results show ontogenetic variation in the type ofbone tissues deposited throughout the development of C. latirostris. This studyoffers a broad framework for life history interpretations for C. latirostris and providesinsight into the evolutionary history and ontogenetic growth of extinct crocodylianlineages.