Arietites is a genus of massive, giant evolute, psiloceratacean ammonites in the family Arietitidae in which whorls are subquadrate and transversely ribbed and low keels in triplicate, separated by a pair of longitudinal grooves, run along the venter. Fossils are known world wide from the lower Sinemurian stage of the Lower Jurassic. Safari Ltd made an Arietites bucklandi figurine in 2014.
Similar genera include Megarietites in which the keels are reduced and Epammonites in which the ribs are more closely spaced.
Species Arietites ablongaris Arietites alcinoe Reynès, 1879 Arietites anastreptoptychus Franz Wähner, 1891 (possibly a synonym of Paracaloceras subsalinarium; Wähner) Arietites bisulcatus Arietites bonnardii Alcide Dessalines d'Orbigny, 1879 Arietites brookei Arietites bucklandi George Brettingham Sowerby, 1816 Arietites crossi Arietites gaudryi Reynès Arietites geometricus Albert Oppe, 1856 Arietites hettangiensis Arietites isis Arietites longicellus Friedrich August Quenstedt, 1858 Arietites meigeni, (possibly a synonym of Leptechioceras meigeni) Arietites meridionalis Reynès Arietites obesulus J. F. Blake, 1876 Arietites obtusus Arietites pinguis Arietites planaries Reynès, 1879 Arietites quadratus E. Donovan, 1952 Arietites radiatus C. T. Simpson, 1843 Arietites retroversicostatus Canavari Arietites rotiformis Sowerby Arietites scunthorpense Arietites semicostatus A. T. Young & Bird, 1828 Arietites spiratissimus Arietites subsalinarius Wähner, 1891, (possibly a synonym of Paracaloceras subsalinarium; Wähner) Arietites tenellus C. T. Simpson, 1855 Arietites turneri Arieties westfalicus Lange (possibly a synonym of Coroniceras westfalicum Lange, 1925) Arietites wichmanni August Rothpletz, 1892
Note: Arietites now only represents a purely morphological term. A revision of the genus is still pending, its representatives are therefore initially classified as Coroniceras (Arietites) under Coroniceras .
References
Further reading Arkell, et al. 1957. Mesozoic Ammonoidea. Treatise on Invertebrate Paleontology. Geological Soc. of America and Univ. of Kansas Press.