Reptile fossils are important fossil finds from the Fossil Butte Member (FBM). Aquatic (water based) and terrestrial (land based) reptile fossils help scientists understand the ecosystem of Fossil Lake and its surrounding environment. 15 species of reptiles have been identified from the FBM.
Snake - Boavus idelmaniOrder Squamata, Family Boidae
The family Boidae has 44 living species found mostly in tropical and subtropical regions of Central and South America, Europa, Africa, Asia, and the western United States. Snakes in the Boidae family are carnivorous and a few are aquatic. B. idelmani is small and may belong to the neotropical subfamily Tropidophinnac (dwarf boas).
Snakes are a very rare find from the Fossil Butte Member (FBM). Only 1 species has been identified from a small number of specimens. In 2017, a fossil specimen appearing to be a snake of a different species was found in the FBM. Identification of this new snake species is pending.
Lizards - 3 Species Identified: Saniwa ensidens & Bahndwivici ammoskius & Afairiguana aviusOrder Squamata
The Shinisauridae family (crocodile lizards) contains one modern species, Shinisaurus crocodilurus. S. crocodilurus is:
The more than 300 modern members of the Iguanidae family:
Crocodilians - 2 Species Identified: Borelosuchus wilsoni & Tsoabichi greenriverenisOrder Crocodilia
B. wilsoni belongs to a primitive crocodilian group and was neither true crocodile nor true alligator. It was part of a sister group to the group that contains both modern crocodiles and alligators. The largest B. wilsoni specimen discovered from the FBM was about 15 feet long. Growth rings in B. wilsoni fossil teeth indicate this species could grow as large as 16 feet long.
T. greenriverenis belongs to the subfamily Caimaninae (caimans), one of the two primary lineages of the Alligatoridae family. The 6 living caiman species are native to tropical and subtropical regions of Central and South America. They inhabit slow moving, freshwater streams, lakes, ponds, and flooded wetlands. Modern caimans feed on insects, amphibians, crayfish, shrimp, and birds.
Turtles - 8 Species IdentifiedAll identified turtle species had aquatic or semi-aquatic habits. The species below are organized by family.
Baenidae Turtles - 2 Species Identified: Chisternon undatum & Baena arenosaOrder Testudines, Family Baenidae
The extinct Baenidae family:
Soft-Shell Turtles - 3 Species Identified: Apalone heteroglypta & Axestemys byssinus & Hummelichelys guttataOrder Testudines, Family Trionychidae
Members of the Trionychidae family:
Both A. heteroglypta and A. byssinus would have been apex (top of the food chain) or near-apex predators of Fossil Lake.
River Turtle - Baptemys wyomingenisOrder Testudines, Family Dermatemydidae
The Dermatemydidae family has only one living species, Dermatemys mawii. D. mawii is:
Pond Turtle - Echmatemys wyomingensisOrder Testudines, Family Emydidae
Living members of the Emydidae family:
Last updated: September 29, 2017