Shastoceras
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
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