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tubular sperm conduit associated with the anal fin). Among all ostariophysans, 

 which comprise about 72% of the world's freshwater fishes, internal fertihzation has 

 only been demonstrated in one other group, the so-called glandulocaudine characins 

 (Weitzman and Fink 1985), despite the independent evolution of internal fertilation 

 in many other teleost lineages (Gross and Shine 1981). Thus, there is no evidence 

 to suggest that this phenomenon arose independently in auchenipterids and 

 ageneiosids. 



The reproductive biology of ageneiosids and auchenipterids has been grossly 

 neglected in the past. Given the unique morphology of these fishes and their 

 unusual reproductive biology, future studies will be extremely valuable in providing 

 information about their systematics, and about the evolution of reproductive life- 

 history patterns m neotropical fishes. , ■■': 



■f\ -ii^i* / i 



