Analytoceras  Analytoceras is an extinct genus of cephalopod belonging to the Ammonite subclass that lived during the early Jurassic. "Analytoceras", named by Alpheus Hyatt in 1900, is a lytoceratid and only member of the pleuroacanthitid subfamily Analytoceratinae, which has the same characters as its genus. Shell characters: inner whorls constricted, middle with parabolic lines and conspicuous parabolic nodes, outer with sigmoidal flairs; adult body chamber with ventrolateral spines.