Language: English
Language: English
The diagnosis, composition, and phylogenetic relationships of the Chanidae, an ostariophysan fish family of the order Gonorynchiformes, are revised. A cladistic analysis is carried out in order to test previous phylogenetic hypotheses and the monophyly of this family. The material examined consists on several Mesozoic taxa traditionally assigned to the Chanidae and several living Gonorynchiformes, including Chanos chanos. The results provide new synapomorphies of the order Gonorynchiformes, and reject some previously proposed synapomorphies. The monophyly of the Chanidae is confirmed on the basis of fourteen synapomorphies, nine of which are uniquely derived characters. These synapomorphies provide the basis for the new diagnosis of this family. Chanos is not the sole member of the family Chanidae. The analysis confirms that the fossil taxa considered in the study (Aethalionopsis, Dastilbe, Gordichthys, Parachanos, Rubiesichthys, and Tharrhias) must also be included within the chanids. This implies independent evolution of the caudal endoskeleton in Chanos and in the other Recent gonorynchiforms.
The Spanish Early Cretaceous forms Rubiesichthys gregalis and Gordichthys conquensis are sister-taxa, forming the subfamily Rubiesichthyinae n. subfam. This clade is the sister-group to all other chanids, which form the subfamily Chaninae n. subfam. Rubiesichthys and Gordichthys are the oldest fossil record of the family Chanidae and of the order Gonorynchiformes.