f -* '■-' :'--- ^J '>" 









PHYLOGENETIC RELATIONSHIPS 



The purpose of the present study is to resolve the taxonomy of the species 

 that have hitherto been classified in the family Ageneiosidae, and to propose a 

 provisional cladistic hypothesis of relationships among these species. At the onset 

 of this study, it became apparent that there are significant taxonomic problems at 

 the generic and famiUal levels involving ageneiosids and several other larger groups 

 of catfishes, and that these problems could not be ignored if a revision of the 

 Ageneiosidae were to be adequately accomplished. I have not personally attempted 

 to analyze any of the more significant higher-level problems that exist, nor have I 

 examined a large number of species in outgroups or sister taxa. Rather, I have 

 reUed on published data that are available, many of which are anecdotal or limited 

 in scope to relatively few taxa. Additionally, I have relied on some other more 

 extensive unpubUshed sources for anatomical and systematic information. 

 Fortunately, there has been a very recent surge of interest in catfish systematics, as 

 evidenced by an increase in the number of pubhshed papers, but we are only 

 beginning to unravel the myriad of systematic complexity of this remarkable order. 

 Attention to the neotropical doradoids has been relatively limited in the past, but 

 the following people have recently completed graduate degrees based on systematic 

 studies of various subgroups: Cari J. Ferraris (AMNH; auchenipterid relationships); 

 Daniel J. Curran (UCLA; auchenipterid relationships); Horacio Higuchi (MCZ; 

 doradid subgroups); and, Roberto Royero (MBUCV); dorsal fin of siluroids). In 

 addition to these individuals, I must mention Heraldo Britski (MZUSP), whose 

 unpublished doctoral dissertation was a result of the first comprehensive study of 



148 ..'./^'^ -,.^ 



