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Related to Crossopterygii: crossopterygians
Crossopterygiia subclass of the class Choanichthyes, an ancient group of mainly freshwater fish, including many fossil forms but only a single living species, the COELACANTH Latimeria.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005