ABSTRACT
The superorder Osteoglossomorpha is a monophyletic group with a relatively well-preserved fossil record extending from Late Jurassic to Oligocene in the freshwater deposits of the world. Both cladistic vicariance and dispersal events, combined with extinctions, could have contributed to establishing of the Recent transoceanic distribution of this teleostean group. Based on the age and distribution of the group, the most likely ancient landmass available as an ancestral distribution area of Osteoglossomorpha is Pangea; that is, the early development of Osteoglossomorpha in Pangea was probably completed by the Middle to the Late Jurassic, and the earliest of the main lineages of this group had already enlarged their distribution to most parts of Pangea before its final fragmentation. It is also suggested that the YLycopteriformes is a clade endemic only to East Asia as East Asia was isolated from Euramerica and all the southern continents during Late Jurassic to Early Cretaceous time, and the order has never been found elsewhere. Fossil evidence from the Lower Tertiary of all the main continents except Antarctica suggests an “Early Tertiary global diversification” of Osteoglossomorpha. The Recent distribution of this freshwater fish group has probably resulted from extinction of the Osteoglossiformes from North America, East Asia, and Europe, and the Hiodontiformes from East Asia and far western North America (now the Rocky Mountains area).
