Frechiella
Encyclopedia
Frechiella is an ammonite
with a smooth, somewhat globose involute shell that lived during the later part of the Early Jurassic, which has been found in England and Italy. The shell is coiled so that the outer whorls cover most of the inner, leaving the inner whorls only slightly exposed. The outer rim, known as the venter, is broadly arched, with either a low narrow keel bordered by small grooves, or a large median groove.
Frechiella is included in the Hildoceratidae, a family of Jurassic ammonoid cephalopods that are part of the Hildocerataceae
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Ammonitida
The Ammonitida is an order of more highly evolved ammonoid cephalopods from the Jurassic and Cretaceous time periods, commonly with intricate ammonitic sutures....
with a smooth, somewhat globose involute shell that lived during the later part of the Early Jurassic, which has been found in England and Italy. The shell is coiled so that the outer whorls cover most of the inner, leaving the inner whorls only slightly exposed. The outer rim, known as the venter, is broadly arched, with either a low narrow keel bordered by small grooves, or a large median groove.
Frechiella is included in the Hildoceratidae, a family of Jurassic ammonoid cephalopods that are part of the Hildocerataceae
Hildocerataceae
Hildocerataceae is a superfamily of compressed or planulate ammonites, some tending to develop acute outer rims; generally with arcuate or sigmoidal ribs. Aptichus were found in place are double-valved....
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References
- ammonites D-G
- Treatise on Invertebrate Paleontology, Part L, 1957. Geological Society of America and University Kansas Press.