Coiling rather irregular, typically in open, plane spiral ending in 2 or 3 more or less parallel shafts; early part may be helical. Section circular to compressed; ribs annular or interrupted on dorsum; no tubercles. The earliest hamitids, some with subtrifid L, appear in the upper Lower Albian and are presumably derived from early Anisoceratidae by loss of tubercles.
Genus: Hamites PARKINSON, 1811
Type species: Hamites attenatus J. Sowerby 1814
Typically with 3 well-separated, subparallel shafts, but initial spiral or even helical coiling may persist; whorl section circular, depressed or compressed; straight, rectiradiate or oblique ribs typically fine and dense to coarse and distant, but may be obsolescent.
Subgenus: Hamites (Hamites)
Ribs always present
Hamites (Hamites) attenuatus J. Sowerby, 1814
Hamites (Hamites) rotundus J. Sowerby, 1814
Hamites (Hamites) subrotundus Spath, 1941
Hamites (Hamites) incurvatus Brown, 1837
Hamites (Hamites) maximus J. Sowerby, 1814
Hamites (Hamites) gibbosus J. Sowerby, 1814
Hamites (Hamites) tenuis J. Sowerby, 1814
Hamites (Hamites) intermedius J. Sowerby, 1814
Subgenus: Hamites (Lytohamites) CASEY, 1961
with straight shafts, ribs rather fine, oblique
Hamites (Lytohamites) similis, Casey 1960


Wright C.W. 1996. Treatise on Invertebrate Paleontology; Part L MOLLUSCS 4 Revised (Volume 4: Cretaceous Ammonoidea)


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