Tichkaella

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Tichkaella
Temporal range: Mid Cambrian
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Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Mollusca (?)
Class: Helcionelloida
Order: Helcionelliformes
Superfamily: Helcionelloidea
Genus: Tichkaella

Tichkaella is a genus of helcionellid from the Middle Cambrian. It has a strongly spiralled, smooth shell with concentric ridges that have low relief. Other than its looser coiling, it is very similar to Protowenella . [1]

Protowenella is a genus of helcionellid from the Middle Cambrian of Australia. It has a strongly spiralled, smooth shell with concentric ridges that have low relief. Other than its tighter coiling, it is very similar to Tichkaella.

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References

  1. Peel, J. S. (1991). "Functional Morphology of the Class Helcionelloida Nov., and the Early Evolution of the Mollusca". In Simonetta, A. M.; Conway Morris, S. The Early Evolution of Metazoa and the Significance of Problematic Taxa. Cambridge University Press. pp. 157–177. ISBN   978-0-521-40242-2.