INVESTIGADORES
ABDALA Virginia Sara Luz
artículos
Título:
The jaw adductor muscles across lepidosaurs: a reappraisal
Autor/es:
DAZA, J. D.; DIOGO, R.; JOHNSTON, P.; ABDALA, V.
Revista:
ANATOMICAL RECORD-ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY
Editorial:
WILEY-LISS, DIV JOHN WILEY & SONS INC
Referencias:
Año: 2011
ISSN:
1932-8486
Resumen:
The exact homologies of tetrapod jaw muscles remain unresolved and this provides a barrier for phylogenetic analysis and tracing character evolution. Here, lepidosaur jaw muscles are surveyed using direct examination of species from 23 families and published descriptions of species from 10 families. A revised nomenclature is applied according to proposed homologies with Latimeria. Within lepidosaurs variation was found in many aspects of jaw muscle anatomy. The superficiallayers mm. levator and retractor anguli oris (LAO and RAO ) are present in Sphenodon but not all squamates. The external jaw adductor muscles universally present in lepidosaurs are homologous with the main adductor muscle, A2, of Latimeria, and include four layers: superficialis (A2-SUP), medialis (A2-M), profundus (A2-PRO), and posterior (A2-PVM). The A2-SUP appears divided in Agamidae, Gekkota, Xantusiidae, and Varanidae. The A2-M is layered lateromedial in lizards but anteroposterior in snakes. The names pseudotemporalis (PS) and pterygomandibularis (PTM) are recommended for subdivisions of the internal adductors of reptiles and amphibians since the homology of this muscle with the A3? and A3? of Latimeria remains inconclusive.The intramandibularis of lepidosaurs and Latimeria (A-ω) are homologous. The distribution of six jaw muscle characters was found to plot more parsimoniously on phylogenies based on morphological rather and molecular data. Character mapping indicates that Squamata presents reduction in thedivisions of the A2-M, Scincoidea presents reduction or loss of LAO, and two apomorphic features are found for the Gekkota