Wutinoceras
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| Wutinoceras Temporal range: early Middle Ordovician (Whiterockian) | |
|---|---|
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Cephalopoda |
| Subclass: | Nautiloidea |
| Order: | †Actinocerida |
| Family: | †Wutinoceratidae |
| Genus: | †Wutinoceras Flower (1957, emend.) |
Wutinoceras is a genus of now extinct nautiloid cephalopods of the Wutinoceratidae family. It exhibits orthoconic actinocerids with ventral siphuncles composed of broadly expanded segments.[1][2]
Wutinoceras, as with its family the Wutinoceratidae, has a reticulated canal system within the siphuncle, distinguishing it from later forms with arcuate canal systems. Septal necks, components of the siphuncle that project from the back side of the septa, are cyrtochoanitic (outwardly curved) and may be recumbent. Connecting rings are thick, reflective of the ancestral form.
Varieties
The three varieties of Wutinoceras are based on the form of the siphuncle, and each contains a number of species. These have not been ascribed to subgenera. They include those with broad segments and strongly recumbent brims to the septal necks; those with large segments and rings free ventrally; and those with small segments in which the brims on the dorsal side are sometimes free.[2] The genotype Wutinoceras foerste, which comes from northeast China (Manchuria), is of the second variety.