Phareodus testis
Green River Formation
Middle Eocene
Lincoln County, Wyoming

Here is a very good example of a “split” juvenile Phareodus. This specimen is exactly as found in the field. Layers of the ancient Green River Formation lacustrine deposits are split with hammer and chisel to reveal the fossilized fish skeletons enclosed. This juvenile example displays typical preservation of the skeleton, scales, and teeth. The fish measures 12 cm. The slab is 9 x 5 inches. There is no restoration of any kind.

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.