| Acanthoceratoidea Temporal range: Upper Cretaceous |
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|---|---|
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Cephalopoda |
| Subclass: | †Ammonoidea |
| Order: | †Ammonitida |
| Suborder: | †Ammonitina |
| Superfamily: | †Acanthoceratoidea Hyatt, 1900 |
| Families | |
|
see text |
|
Acanthoceratoidea, formerly Acanthocerataceae, is a superfamily of extinct Upper Creataceous ammonoid cephalopods belonging to the order, Ammonitida, and comprising some 10 or so families.[1]
Members of the Acanthoceratoidea are typically strongly ribbed and have a tendency to develop proninent tubercles, although other types including those with oxyconic shells are included.[1]
Families included in the Treatise on Invertebrate Paleontology, Part L[1] are:
According to Wright Calloman, and Howarth. 1996,[2] in the revised version of Part L of the Treatise, the Binneyitidae is replaced by the Forbesiceratidae with the Binneyitidae now in the Hoplitaceae and the Forbesiceratidae included in the Acanthocerataceae. The Leymeriellidae, based on the Lower Albian genus, Leymeriella, was added, extending the range downward. The name Tissotiidae was replaced by Pseudotissotiidae. The Libycoceratidae, proposed by Zaborski, 1982, for the Upper Campainian - Maastrictian Libycoceras, was split of from the Sphenodiscidae.[3] while the other families remain essentially the same, except for the addition of newer genera.
The replacement of the Tissotiidae by the Pseudotissotiidae in the revised classification of the Acanthoceraticeae in the Treatise (1996) is based on the earlier appearance of the subfamily Psudotissotiinae in the Lower Turonian, followed by the Tissotiinae in the Upper Turonian. Other newer classifications e.g.[4] split the Tissotiidae into two families, the earlier Pseudotissotiidae and the later, revised but smaller, Tissotiidae. Fatmi and Kennedy, 1999, returned Libycoceras, sole genus of the Libycoceratidae, to its original position in the Sphenodicidae, so negating the Libycoceratidae.