Radstockiceras

Radstockiceras is an extinct genus of lower Jurassic ammonite that lived from Oxynotum zone of upper Sinemurian to Raricostatum zone of lower Pliensbachian. Shells of these animals were oxycone and involute with umbilicus that took maximum of 12% of diameter in the case of outer whorls. On inner whorls, venter has been sharp, but then it became rounded. Faint ribs had falcoid shape, but sometimes, ribs could absent. Shells could have been large in their size. Suture has been very complex, similar to Oxynoticeras, but culmination at umbilical margin has been missing.[1] Genus has been named after town of Radstock, in Somerset.[3]

Radstockiceras Temporal range: Sinemurian–Pliensbachian[1][2] PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Cephalopoda
Subclass:	Ammonoidea
Order:	Ammonitida
Superfamily:	Psiloceratoidea
Family:	Oxynoticeratidae
Genus:	Radstockiceras Buckman, 1918
Type species
Radstockiceras complicatum Buckman, 1918
Species
R. buvigneri d’Orbigny, 1844 R. complanosum Simpson, 1855 R. complicatum Buckman, 1918 R. coynarti d’Orbigny, 1844 R. fastigatum Venturi et al, 2005 R. gemmellaroi Pompeckj, 1906 R. hechingense Schlatter, 1980 R. involutum Pompeckj, 1906 R. lynx d’Orbigny, 1844 R. oscensis Rivas, 1977 R. pseudosaemanni Rivas, 1977 R. wiltshirei Wright, 1881
Synonyms
Fastigiceras Buckman, 1919 Retenticeras Buckman, 1920 Metoxynoticeras Spath, 1922 Phylloxynoticeras Buckman, 1924 Homoxynoticeras Buckman, 1925 Kleistoxynoticeras Buckman, 1925 Carixiceras Spath, 1925 Radstokiceras Roman, 1938 Oxynoticeroides Dommergues et al, 1986

Distribution

Fossils belonging to this genus are found in Europe, South America, North Africa and Turkey.[1][4]

Sources

1. M. K. Howarth 2013. Treatise on Invertebrate Paleontology, Part L, Revised, Volume 3B, Chapter 4: Psiloceratoidea, Eoderoceratoidea, Hildoceratoidea.
2. Sepkoski, Jack (2002). "Sepkoski's Online Genus Database". Retrieved 2014-05-28.
3. Schlegelmilch, R. (1992). Die Ammoniten des süddeutschen Lias: ein Bestimmungsbuch für Fossiliensammler und Geologen. Springer Spektrum.
4. Radstockiceras on the Paleobiology Database.