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Abstract:

Lacustrine interbeds of a volcaniclastic succession that crops out extensively in north-western Patagonia yielded impressions of articulated, nearly complete, frogs of different ontogenetic stages including tadpoles. The stratigraphic position of the fossil bearing beds in this sequence and evaluation of palaeofloristic data against the record of climatic change in southern high latitudes support a middle Eocene - early Oligocene age for the frogs. These frogs are described as a new genus and species that resembles the late Palaeocene 'Xenopus' romeri from Brazil, and differs from the middle Eocene S. pascuali from Patagonia, in the relatively wide and short braincase and fused first two presacral vertebrae. However, unlike 'X.' romeri, the nasals are paired and bear short, but distinct, rostral processes. A parsimony analysis based on 49 adult osteological characters demonstrates that these South American fossil pipids are closely related to xenopodines, restricted to the African continent today, although their interrelationships remain poorly resolved. Interpretation of the ontogenetic stages exemplified by the fossil specimens suggests a developmental pattern more similar to that of extant xenopodines than to the ontogeny of more distant pipoid relatives. Moreover, the similarity between these fossil larvae and those of Xenopus and Silurana strongly suggests similar habits. Many of these larval features may be considered as caenogenetic, i.e. specializations of the tadpoles as obligate, microphagous suspension feeders. © 2003 The Linnean Society of London.

Registro:

Documento: Artículo
Título:Ontogeny of a new Palaeogene pipid frog from southern South America and xenopodinomorph evolution
Autor:Báez, A.M.; Pugener, L.A.
Filiación:Departamento de Geología, Facultad de Ciencias Exactas, Ciudad Universitaria, 1428 Buenos Aires, Argentina
Natural History Museum, Dyche Hall, University of Kansas, Lawrence, KS 66045, United States
Palabras clave:Gondwana; Patagonia; Pipidae; Shelania; Silurana; Xenopodinae; Xenopus; Anura; Pipidae; Pipoidea; Silurana; Xenopodinae
Año:2003
Volumen:139
Número:3
Página de inicio:439
Página de fin:476
DOI: http://dx.doi.org/10.1046/j.1096-3642.2003.00085.x
Título revista:Zoological Journal of the Linnean Society
Título revista abreviado:Zool. J. Linn. Soc.
ISSN:00244082
CODEN:ZJLSA
Registro:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00244082_v139_n3_p439_Baez

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Citas:

---------- APA ----------
Báez, A.M. & Pugener, L.A. (2003) . Ontogeny of a new Palaeogene pipid frog from southern South America and xenopodinomorph evolution. Zoological Journal of the Linnean Society, 139(3), 439-476.
http://dx.doi.org/10.1046/j.1096-3642.2003.00085.x
---------- CHICAGO ----------
Báez, A.M., Pugener, L.A. "Ontogeny of a new Palaeogene pipid frog from southern South America and xenopodinomorph evolution" . Zoological Journal of the Linnean Society 139, no. 3 (2003) : 439-476.
http://dx.doi.org/10.1046/j.1096-3642.2003.00085.x
---------- MLA ----------
Báez, A.M., Pugener, L.A. "Ontogeny of a new Palaeogene pipid frog from southern South America and xenopodinomorph evolution" . Zoological Journal of the Linnean Society, vol. 139, no. 3, 2003, pp. 439-476.
http://dx.doi.org/10.1046/j.1096-3642.2003.00085.x
---------- VANCOUVER ----------
Báez, A.M., Pugener, L.A. Ontogeny of a new Palaeogene pipid frog from southern South America and xenopodinomorph evolution. Zool. J. Linn. Soc. 2003;139(3):439-476.
http://dx.doi.org/10.1046/j.1096-3642.2003.00085.x