Micromorphology of osteoderms in Dasypodidae (Cingulata, Mammalia): Characterization and 3D‐reconstructions

SCARANO, ALEJO C.; CIANCIO, MARTIN R.; BARBEITO-ANDRÉS, JIMENA; BARBEITO, CLAUDIO G.; KRMPOTIC, CECILIA M.

JOURNAL OF MORPHOLOGY

WILEY-LISS, DIV JOHN WILEY & SONS INC

Lugar: New York; Año: 2020 vol. 281 p. 256 - 272

0362-2525

Osteoderms are present in a variety of extinct and extant vertebrates, but amongmammals, the presence of osteoderms is essentially restricted to armadillos(Cingulata, Dasypodidae). Osteoderms have been proposed to exhibit a variety offunctionalities in Dasypodidae, mainly protection and thermoregulation, and theyhave been considered as one of the synapomorphies of this group. In this study, weuse high-resolution microcomputed tomography to describe the osteoderm micromorphology of several extant species of Dasypodidae in a comparative context. Thisstudy allowed the identification, 3D-reconstruction and volume quantification of different internal structures of osteoderms as well as their interrelations. This detailedcharacterization of the internal osteoderm morphology was compared in a phylogenetic context to assess the evolutionary trends of the species involved. This enablesthe identification of distinctive patterns for the most widely recognized clades, theDasypodinae and Euphractinae with a morphological homogeneity in the microstructure of their osteoderms, in comparison with Tolypeutinae where it has not beenpossible to establish a common morphological pattern. The most important featuresfor linage differentiation is the degree of compaction of the osteoderms, the numberof cavities and the development of hairs. It is likely that the differential developmentof the various structures occurred as adaptive response to climate changes.