Superregnum: Eukaryota
Cladus: Unikonta
Cladus: Opisthokonta
Cladus: Holozoa
Regnum: Animalia
Subregnum: Eumetazoa
Cladus: Bilateria
Cladus: Nephrozoa
Cladus: Protostomia
Cladus: Spiralia
Cladus: Lophotrochozoa
Phylum: Mollusca
Classis: Cephalopoda
Subclassis: † Ammonoidea
Ordo: † Ammonitida
Subordo: †Ammonitina
Superfamilia: Acanthocerataceae
Familia: Vascoceratidae
Subfamiliae: Vascoceratinae
Name
Vascoceratidae Douvillé, 1912
References
The Paleobiology Database Accessed on 12/12/08
The Vascoceratidae is a family of Upper Cretaceous ammonites in the superfamily Acanthoceratoidea characterized by shells that are either smooth or bluntly tuberculate, or have sparse, coarse ribs. Sutural elements are shallow, irregular, and slightly indented, or deep and very indented. Whorl section and degree of involution vary, even within species.
The Vascoceratidae is a short lived family restricted to the early and middle Turonian stage. Its duration, no more than a few million years. They are derived from the Acanthoceratidae and are the predecessors of the Tissotiidae, which in turn gave rise to the Coilopoceratidae; all taking place in a short time span in the Turonian.
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