Artículo
Dermal armour histology of aetosaurs (Archosauria: Pseudosuchia), from the Upper Triassic of Argentina and Brazil
Fecha de publicación:
09/2011
Editorial:
Wiley Blackwell Publishing, Inc
Revista:
Lethaia
ISSN:
0024-1164
Idioma:
Inglés
Tipo de recurso:
Artículo publicado
Clasificación temática:
Resumen
One of the most striking features documented in aetosaurs is the presence of an extensive bony armour composed of several osteoderms. Here, we analyse the bone microstructure of these elements in some South American Aetosaurinae aetosaurs, including Aetosauroides scagliai. In general terms, Aetosaurinae osteoderms are compact structures characterized by the presence of three tissue types: a basal cortex of poorly vascularized parallel-fibred bone tissue, a core of highly vascularized fibro-lamellar bone, and an external cortex of rather avascular lamellar bone tissue. Sharpey’s fibres are more visible at the internal core, toward the lateral margins and aligned parallel to the major axis of the dermal plate. No evidence of metaplastic origin is reported in the osteoderms, and we hypothesize an intramembranous ossification for these elements. The bone tissue distribution reveals that the development of the osteoderm in Aetosaurinae starts in a position located medial to the plate midpoint, and the main sites of active osteogenesis occur towards the lateral and medial edges of the plate. The osteoderm ornamentation is originated and maintained by a process of resorption and redeposition of the external cortex, which also includes preferential bone deposition in some particular sites. Given that no secondary reconstruction occurs in the osteoderms, growth marks are well preserved and they provide very important information regarding the relative age and growth pattern of Aetosaurinae aetosaurs.
Archivos asociados
Licencia
Identificadores
Colecciones
Articulos(CCT - PATAGONIA NORTE)
Articulos de CTRO.CIENTIFICO TECNOL.CONICET - PATAGONIA NORTE
Articulos de CTRO.CIENTIFICO TECNOL.CONICET - PATAGONIA NORTE
Articulos(INIBIOMA)
Articulos de INST. DE INVEST.EN BIODIVERSIDAD Y MEDIOAMBIENTE
Articulos de INST. DE INVEST.EN BIODIVERSIDAD Y MEDIOAMBIENTE
Articulos(MACNBR)
Articulos de MUSEO ARG.DE CS.NAT "BERNARDINO RIVADAVIA"
Articulos de MUSEO ARG.DE CS.NAT "BERNARDINO RIVADAVIA"
Citación
Cerda, Ignacio Alejandro; Desojo, Julia Brenda; Dermal armour histology of aetosaurs (Archosauria: Pseudosuchia), from the Upper Triassic of Argentina and Brazil; Wiley Blackwell Publishing, Inc; Lethaia; 44; 9-2011; 417-428
Compartir
Altmétricas