Kingdom Animalia Class Cephalopoda Order Ammonitida Rank Family | Phylum Mollusca Subclass Ammonoidea Suborder Ammonitina | |
Similar Echioceratidae, Dactylioceratidae, Hildoceratoidea, Hildoceratidae | ||
Phricodoceratidae is a family in the Eoderocerataceae, aberrant ammonites from the Lower Jurassic characterized by a large adult size and a marked change of shell form and ornament with growth. Shells are stoutly ribbed, early growth stage is round-whorled with spines, followed by a high-whorled late growth stage with smooth, modified ribbing.
Three genera are currently placed in the Phricodoceratidae: Phricodoceras, Epideroceras, and Pseuduptonia.
References
Phricodoceratidae Wikipedia(Text) CC BY-SA