Stephanoceras is an extinct genus of Stephanoceratoid ammonite which lived during the Bajocian. It is the type genus of the family Stephanoceratidae.
Australiceras is an extinct ammonite genus from the upper part of the Early Cretaceous, Aptian stage, included in the family Ancyloceratidae.
Algerites is middle Cretaceous (Cenomanian) anisoceratid ammonoid with a close-coiled adult shell in which the whorls at that stage are in close contact, after starting off with openly coiled whorls, and in which every rib has a pair of sharp ventral tubercles.
Aulacosphinctoides is an extinct ammonoid cephalopod that lived during the Late Jurassic, included in the ammonitid family Perisphinctidae.
Astiericeras is an ammonite from the Lower Cretaceous, the shell of which is evolute, stout; outer whorl with strong, well spaced, transverse ribs that cross smoothly over the broad venter; early whorls with lateral tubercles. The outer, mature whorl separates from the coil but hooks back quickly, referred to as a heteromorph.
Arnioceras is an extinct genus of large, evolute, discoidal ammonite from the Lower Jurassic. The shell is normally coiled so that all whorls are exposed. Sides bear strong sharp ribs that are straight until reaching the ventrolateral edge where they swing forward and fade. The rim (venter) is keeled and free of grooves.
Bradfordia is a moderately involute to involute genus included in the ammonoid cephalopod family Oppeliidae, coiled so that the outer whorl encloses most, or much, of the previous, but with a small umbilicus exposing inner whorls. The shell is compressed, whorl height much greater than width, extending well out from the contact with the adjacent inner whorl. Outer flanks are finely ribbed and the rounded venter is smooth.
Euaptetoceras is an evolute hildoceratoid ammonite from the lower Middle Jurassic, included in the family Hammatoceratidae and the subfamility Hammatoceratinae. The genus may be a junior synonym for Eudmetoceras of Buckman, 1920.
Durotrigensia is a genus of ammonites (Ammonitida) in the perisphinctoid family Parkinsoniidae.
Oecoptychius is an extinct genus of fossil ammonite cephalopods. The species lived during the Middle Jurassic.
Normannites is a strongly ribbed evolute Middle Jurassic genus of ammonite included in the stephanoceratoid family Stephanoceratidae.
Clymenia is a genus in the ammonoid order Clymeniida, restricted to the Upper Devonian, characterized as with all clymeniids by a dorsal siphuncle that runs along the inside of the whorls, unusual for ammonoids.
Exiteloceras is an ammonite genus from the Late Cretaceous.
Hoploscaphites is an extinct ammonite genus from the Upper Cretaceous and the Lower Paleocene, included in the family Scaphitidae.
Permoceras, the sole member of the family Permoceratidae, is a genus of coiled nautiloids with a smooth, compressed involute shell, whorls higher than wide, earlier whorls hidden from view. The venter is rounded as are the ventral and umbilical shoulders, the flanks flattened. The siphuncle is ventrally subcentral. The suture, which is most characteristic, has a deep, narrow pointed ventral lobe and large, asymmetrical pointed lobes on either side.
Titanoceras is an extinct genus in the nautiloid order Nautilida from the Pennsylvanian and Lower Permian of North America and Western Australia.
Tylonautilus is an extinct genus in the nautiloid order Nautilida from the Lower Carboniferous of Europe and Permian of Japan.
Crucilobiceras is an ammonoid cephalopod genus from the Lower Jurassic belonging to the eoderoceratoidean family Eoderoceratidae. Cruciliboceras has an evolute shell, such that all whorls are well exposed, with persistent radial ribbing and with spines or tubercles on the outer, ventral, rim, and in some, tubercles in the inner, umbilical, rim. The genus Crucilobiceras is commonly found along the Jurassic Coast of England.
Hauericeras is an ammonite genus from the Late Cretaceous that lived from the Coniacian to the late Maastrichtian, from about 90 to 66 mya. Fossils have been found in Europe, Russia, South Africa, Australia, India, Iraq, and in the United States.
Schlotheimia is a genus of extinct cephalopods belonging to the subclass Ammonoidea that lived during the Hettangian stage at the beginning of the Early Jurassic.
