Phricodoceratidae Temporal range: | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Cephalopoda |
Subclass: | †Ammonoidea |
Order: | †Ammonitida |
Superfamily: | †Eoderoceratoidea |
Family: | †Phricodoceratidae Spath, 1938 |
Genera | |
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Phricodoceratidae is a family in the Eoderoceratoidea, 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
- Arkell et al., 1957. Mesozoic Ammonoidea, in Treatise on Invertebrate Paleontology, (Part L); Geological Soc. of America and University of Kansas press.
- Donovan, Callomon, and Howarth 1981 Classification of the Jurassic Ammonitina; Systematics Association.
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