Shastoceras
Appearance
Shastoceras Temporal range: Early Aptian
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Shastoceras behemoth & S. californicum | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Cephalopoda |
Subclass: | †Ammonoidea |
Order: | †Ammonitida |
Suborder: | †Ancyloceratina |
Family: | †Ancyloceratidae |
Genus: | †Shastoceras Anderson, 1938 |
Species | |
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Shastoceras is a genus of extinct ammonites found in Lower Aptian sediments in Northern California. Although sometimes placed in the Heteroceratidae, a family characterized by a helically wound early portion, its form indicates it more likely belongs to the Ancyloceratidae.[citation needed]
Shastoceras resembles Uhligia from the Lower Barremian of Germany, except for being stouter. In both genera the initial portion is short and in general straight, followed by a more or less 180 deg. bend and a straight to moderately curved shaft ending in a hook. The shaft of Shastoceras is shorter and broader than that of Uhligia.
References
[edit]- W.J. Arkell, et al., 1957. Mesozoic Ammonoidea; Treatise on Invertebrate Paleontology, Part L. Geological Society of America and University of Kansas Press.