On the osteology and myology of the cephalic region and pectoral girdle of Franciscodoras marmoratus (Lutken 1874), comparison with other doradids, and comments on the synapomorphies and phylogenetic relationships of the Doradidae (Teleostei: Siluriformes)

The cephalic and pectoral girdle structures of Franciscodoras marmoratus are described and compared to those of representatives of the three main doradid groups, namely Anadoras weddellii (Astrodoradinae), Acanthodoras cataphractus (Platydoradinae) and Doras punctatus (Doradinae), as well as members of the other siluriform families, as the foundation for a discussion on the phylogenetic relationships of the Doradidae. Our observations and comparisons support the idea that the Doradidae is closely related to the Auchenipteridae. In addition, our observations and comparisons pointed out a potentially new doradid synapomorphy, namely, the presence of a well-developed, deep, oval fossa between the dorsomedian surface of the pterotic and the dorsolateral surface of the parieto-supraoccipital.