Tornoceratina
Appearance
This article includes a list of references, related reading, or external links, but its sources remain unclear because it lacks inline citations. (March 2015) |
Tornoceratina Temporal range:
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The prionoceratid Imitoceras rotatorium. Early Carboniferous, Rockford Limestone, Rockford, Illinois. | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Cephalopoda |
Subclass: | †Ammonoidea |
Order: | †Goniatitida |
Suborder: | †Tornoceratina Wedekind, 1914 |
Superfamilies | |
Tornoceratina is one of two suborders included in the Goniatitida, characterized by generally involute, subdiscoidal shells and by sutures in which the ventral ones are undivided.
Sutural lobes increase in number during the course of life of the individual, typically developed from the internal and external saddles. The siphuncle is prochoanitic, with septal necks projecting forward.
Derivation is from the Anarcestida in the middle Devonian.
References
[edit]- Miller, Furnish, and Schindewolf, 1957. Paleozoic Ammonoidea. Treastise on Invertebrate Paleontology, Part L. Geological Society of America.
- Tornoceratina in Goniat on line, Mar. 5, 2015
- The Paleobiology Database Oct.1, 2007