Ontogeny and tissue differentiation of the pelvic girdle and hind limbs of anurans

ADRIANA MANZANO; VIRGINIA ABDALA; MARIA LAURA PONSSA; MONICA SOLIZ

ACTA ZOOLOGICA

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2013 vol. 94 p. 420 - 436

0001-7272

We present the ontogeny of the integrated musculoskeletal complex that comprises thepelvic girdle and hind limbs of anurans. Our histological data show that the pelvic girdleoriginates from a single mesenchymatic condensation. The tissue differentiation sequenceis: cartilage, muscle and tendon. The intrusion of the ischiadic nerve into the limb bud isproduced very early in ontogeny. The precartilage appears in the premotile stage.Therefore, the nerve produces a movement analogous to the «embryonic motility» thatwould induce the emergence of the precartilage. The acetabulum is the first of all cavitationprocesses to form, the second one being the knee. The acetabulum appears before themuscles are mature, although it has been stressed that the muscle contraction maintainsjoint progenitors committed to their fate. Our data indicate an explosive differentiation ofall 11 muscular masses together. We provide three new characters that support themonophyly of Hyloides, Acosmanura and Neobatrachia.