Calycoceras species may be found in the Cretaceous of Angola, Antarctica, Canada (British Columbia), France, Germany, Japan, Nigeria, Oman, Russia, the United Kingdom, United States (Alaska, Arizona, Kansas, New Mexico, South Dakota, Utah) [3]
C. cenomanense may be found in the Cenomanian of United Kingdom, France and Madagascar.[10][11][12][13]
Description
Shells of Calycoceras asiaticum may reach a diameter of about 20 centimetres (7.9 in). The larger phragmocones may reach 59–72 millimetres (2.3–2.8 in) in diameter. Coiling is moderately involute. All ribs show strong subspinose tubercles. C. asiaticum asiaticum and C. asiaticum spinosum are very similar, the latter has much more robust tuberculation.[3][14]
^ William James Kennedy, Ireneusz Walaszczyk, Andrew S. Gale, Krzysztof Dembicz, Tomasz Praszkier - Lower and Middle Cenomanian ammonites from the Morondava Basin, Madagascar
^ W. J. Kennedy 1971. - Cenomanian Ammonites from Southern England. Special Papers in Palaeontology Number 8. v + 133 pp., 64 pls, 5 tables. The Palaeontological Association, London