''Alaskoceras'' is a genus of lower
Ordovician
The Ordovician ( ) is a geologic period and System (geology), system, the second of six periods of the Paleozoic Era (geology), Era, and the second of twelve periods of the Phanerozoic Eon (geology), Eon. The Ordovician spans 41.6 million years f ...
coiled
nautiloid cephalopods; the shell moderately expanded, ribbed, with a divergent living chamber; whorl section more broadly rounded ventrally than dorsally;
siphuncle marginal at maturity,
septal necks short, almost
achoanitic; connecting rings thick, layered.
''Alaskcoceras'' belongs to the
Tarphycerida, and to the family
Estonioceratidae. It was found in Alaska.
References
* W.M Furnish & Brian F. Glenister, 1964. Nautiloidea-Tarphycerida.
Treatise on Invertebrate Paleontology, Part K. Geological Society of America and University of Kansas Press.
Ordovician cephalopods of North America
Prehistoric nautiloid genera
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