A contribution to the comparative osteology and phylogenetic systematics of fossil and living bony-tongue fishes (Actinopterygii, Teleostei, Osteoglossomorpha)

Several recent morphological studies have addressed the interrelationships of Osteoglossomorpha, a group that sometimes is considered the sister group of all other living teleostean fishes. Many characters used in these studies were found to be poorly defined, to be coded incorrectly or illogically, or to display more variation than was described. The goal of this study is to address these concerns and contribute generally to knowledge of the morphology and systematic relationships of osteoglossomorphs. Analysis of 72 characters scored for 20 genera resulted in 2 most parsimonious cladograms. The only difference in the topologies of these cladograms is in the position of †Lycoptera (recovered as either the sister group of all other osteoglossomorphs sampled or of †Eohiodon + Hiodon). †Ostariostoma is recovered as the sister group of all non-hiodontiform osteoglossomorphs. Mormyrids are sister group of notopterids + osteoglossids (including Pantodon). Mormyrids and notopterids usually are considered more closely related to each other than to any other group; characters not included here support this relationship and future consideration of these characters must be made. † Palaeonotopterus is interpreted as sister-group of all mormyrids sampled; however, only 22% of characters could be scored for it and its resemblance to notopterids are undeniable. General problems of character definition are discussed in my review of characters used in previous analyses.