Arctocephalites
Encyclopedia
Arctocephalites is an extinct ammonitic
cephalopod genus from the Middle Jurassic
with a wide northern distribution belonging to the stephanoceratacean family, Cardioceratidae.
The inner whorls of the Arctocephalites shell are sharply ribbed but change abruptly to smooth. The such, as characteristic of the family, is complex with large first lateral lobe and well-developed umbilical lobe.
Arctocephalites has been found in Bathonian age sediments at Cook Inlet, Alaska, in western Montana,and in the North Sea at paleolatitudes ranging from about 30deg N to 50deg N. It has been found in equivalent age sediments in the Volga and Pechora river basin in Russia as well as in Greenland, FanzJoseph Land, NovayZemlya, and eastern Siberia.
Ammonitida
The Ammonitida is an order of more highly evolved ammonoid cephalopods from the Jurassic and Cretaceous time periods, commonly with intricate ammonitic sutures....
cephalopod genus from the Middle Jurassic
Middle Jurassic
The Middle Jurassic is the second epoch of the Jurassic Period. It lasted from 176-161 million years ago. In European lithostratigraphy, rocks of this Middle Jurassic age are called the Dogger....
with a wide northern distribution belonging to the stephanoceratacean family, Cardioceratidae.
The inner whorls of the Arctocephalites shell are sharply ribbed but change abruptly to smooth. The such, as characteristic of the family, is complex with large first lateral lobe and well-developed umbilical lobe.
Arctocephalites has been found in Bathonian age sediments at Cook Inlet, Alaska, in western Montana,and in the North Sea at paleolatitudes ranging from about 30deg N to 50deg N. It has been found in equivalent age sediments in the Volga and Pechora river basin in Russia as well as in Greenland, FanzJoseph Land, NovayZemlya, and eastern Siberia.