Bajocian (Middle Jurassic) Ammonites

During the Middle Jurassic the Twin Creek Limestone was deposited in the Nevada Foreland Basin. Ammonites are found in the Sliderock Member of this Formation.

Reference: Imlay, R. W., 1967, Twin Creek Limestone (Jurassic) in the Western Interior of the United States, U.S.G.S. Professional Paper 540


Megasphaeroceras rotundum Imlay 1962, this specimen is 47mm diameter


Eocephalites primus Imlay 1967, this specimen is 90mm diameter


Stemmatoceras n. sp. aff. S. albertense Mclearn 1928, this specimen is 210mm diameter


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