Kingdom Animalia Phylum Mollusca Order Ammonitida | Family Nostoceratidae Rank Genus Subclass Ammonites | |
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Similar Ammonites, Eubostrychoceras, Ainoceras, Polyptychoceras, Gaudryceras | ||
Muramotoceras was an unusual genus of heteromorphic ammonite. It was known only from Japan until researchers reported in 2001 that the genus was present in Alaska's Matanuska Formation as well. Its remains likely date to the middle Turonian (from 89.8 to 93.9 million years ago) in both areas.
References
Muramotoceras Wikipedia(Text) CC BY-SA