Juvenile Phareodus | Green River Formation | Wyoming

Plate approx. sizes: 5.5" x 4.5"

Fish approx. sizes: 2.75"

Bony-Tongue Fish - 2 Species Identified: Phareodus encaustus & Phareodus testis

Order Osteoglossiformes, Family Osteoglossidae
Living members of the Osteoglossidae family:

• include 10 modern species
• live exclusively in tropical freshwaters
• found in South America, Africa, Asia, and Australia
• mouth-brooders (parents hold eggs and hatchlings in their mouths)

Phareodus fossils:

• adult specimens usually found alone, but juveniles known from mass mortalities
• indicates that Phareodus schooled as a juvenile and became solitary as an adult
• often preserved with smaller fish in their jaws and stomach, indicating they were predators
• rearward oriented fins on back and underside, adaptation for speed
• large, sharp teeth
• max known size of P. encaustus: 30 inches
• max known size of P. testis: 20 inches