Wikipedia
Anahamulina is an extinct ammonoid cephalopod genus from the Lower Cretaceous. Named by Hyatt, 1900, Anahamulina is included in the family Ptychoceratidae, which is part of the Turrilitaceae.
Anahamulina is characterized by an increasingly wide shaft that bends sharply to the opposite direction, at some point ending in a shorter terminal section. The two sections are not in lateral contact. The first, and earlier, shaft has fine, dense, oblique ribs, which in the second, and later, shaft are stronger and more radial.
Two species are recognized. The type Anahamulina subcylindrica, named by Hyatt, 1900, is based on Hamulina subcylindrica d'Orbigny 1850, and is found in Europe and Japan. Anahamulina wilcoxensis named by Imlay, 1960, is known from California and Oregon.