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Chardon (1968) placed ageneiosids, doradids, and auchenipterids together 

 with mochokids as famiUes within his superfamily Doradoidae. His recognition of 

 the superfamily was based on limited similarities of the Weberian apparatus, most 

 notably the presence of an elastic spring mechanism (in modified form in the 

 Ageneiosidae). Chardon (1968) distinguished the doradoid families on the basis of 

 several osteological features that were not regarded by Ferraris (1988) to represent 

 shared, derived characters confined to taxa within each family. 

 , , Britski (1972) improved previous concepts of doradoid interrelationships, 

 specifically within the Ageneiosidae and Auchenipteridae, by invoking a more in- 

 depth analysis of a diversity of characters, including sexual dimorphism and 

 osteology. Britski (1972) discussed in detail his interpretation of the distribution of 

 character states, and he provided a provisional phylogenetic tree of the doradoids, 

 exclusive of taxa within the Doradidae. However, his inferences regarding 

 relationships treated primitive and derived characters equally; his tree was 

 apparently heuristic, and did not explicitly denote character states. In spite of these 

 limitations, Britski's study was the first to present detailed analyses of a wide suite of 

 characters across a fairly broad taxonomic range. In the context of his study, Britski 

 (1972) classified the 13 genera of auchenipterids that were available to him into four 

 subfamilies. He recognized ovUy Ageneiosus and Tetranematichthys within the 

 Ageneiosidae. , - 



Very recently, Royero (1987), Ferraris (1988), and Curran (1989), have 

 offered additional hypotheses of phylogenetic interrelationships within the 

 Doradoidea. Royero (1987) studied the myology and osteology of the dorsal fin and 

 supporting structures in several catfish taxa, including representatives of most of the 

 neotropical families. He recognized the three doradoid groups as distinct famihes. 

 A cladogram of the "Doradina" given by Royero (1987) included the Ageneiosidae 

 as the most derived group (with Tetranematichthys at a basal position within the 









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