Morphology of the gas bladder in thorny catfishes (Siluriformes: Doradidae)

Author(s)

Birindelli, Jose L. O. ^[1] ; Sousa, Leandro M. ^[1] ; Perez, Mark H. Sabaj ^[2]

Affiliation

^[1] Univ Sao Paulo, Museu Zool, BR-04218970 Sao Paulo - Brazil

^[2] Acad Nat Sci Philadelphia, Dept Ichthyol, Philadelphia, PA 19103 - USA

• Document type: Journal article
• Source: PROCEEDINGS OF THE ACADEMY OF NATURAL SCIENCES OF PHILADELPHIA; v. 158, p. 261-296, APR 2009.
• Web of Science Citations: 31

Abstract

The gross morphology of the gas bladder is described, illustrated, compared and categorized among 86 of 88 nominal valid and six undescribed species representing all 31 genera of Doradidae with comments on ontogenetic and taxonomic variation when observed. The putatively basal-most doradids exhibit an unmodified cordiform gas bladder. Derived taxa exhibit an impressive suite of modifications including the addition of a secondary bladder, pronounced reduction of the posterolateral chambers, internal trabeculae, associations with bony capsule-like expansions of the anterior (Weberian) vertebrae, and accessory diverticula varying widely in size, shape, abundance, and distribution. Intra-specific differences are minor, most often reflective of ontogenetic changes especially in large-size species, whereas inter-specific and inter-generic differences are significant, in many cases diagnostic, and suggestive of phylogenetic signal excepting instances of evident convergence such as gas bladder reduction in Rhynchodoras and all but one species of Leptodoras. (AU)

• FAPESP's process: 06/04162-1 - Taxonomic review and phylogeny of Astrodoradinae (Siluriformes, Doradidae)
• Grantee: Leandro Melo de Sousa
• Support Opportunities: Scholarships in Brazil - Doctorate