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In vivo Electroporation of Morpholinos into the Regenerating Adult Zebrafish Tail Fin
Published on: March 29, 2012
-Morphological variations in the dorsal fin finlets of extant polypterids raise questions about their taxonomical
Marcos Vinícius Coelho1, Camila Cupello1, Paulo M Brito1
1Departamento de Zoologia, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
Abstract:
Fossil polypterids are mainly represented by disarticulated material, most of them pinnules. However, there is no study that proves the taxonomical validity of these structures. Here we describe the pinnules of four species of extant polypterids and report for the first time intraindividual variations in the pinnules according to their position in the dorsal fin. Nevertheless, when comparing two different specimens of one species there is little or no interindividual variation, suggesting that pinnule morphology may have taxonomical validity. As the fossil polypterid record is based mainly on the articular head of the pinnules, we suggest caution when describing new taxa, especially if different fragments corresponding to specific positions in the dorsal fin occur in the same locality.
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