Phareodus testis
Green River Formation
Middle Eocene
Lincoln County, Wyoming

This is an outstanding and near perfect example of the species from the Fossil Butte Member of the Green River Formation. This specimen has excellent preservation and detail for this locality. Teeth, fins and bones all have exquisite detail. The scales are fantastic. The preparation on this specimen is premier. The fish body is 15 cm long. The slab is 12.5 inches by 15 inches. As a bonus there are skeletons of two nice Diplomystus on the back of the slab. They have not been prepared. There is no repair and only minor restoration of the terminal fin rays.
Phareodus testis is the smaller of the 2 valid species present in the Green River beds. It has a deeper belly and shorter body profile than the larger P. encaustus. They were thought to be solitary fish and are generally not found preserved with other Phareodus individuals. Phareodus is a member of the Osteoglossidae and is represented by 10 living species found exclusively in tropical freshwaters of South America. They are predatory and feed on insects and other fishes.