| Mackinnonia Temporal range:   | |
|---|---|
| Scientific classification  | |
| Domain: | Eukaryota | 
| Kingdom: | Animalia | 
| Phylum: | Mollusca | 
| Class: | †Helcionelloida | 
| Order: | †Helcionelliformes | 
| Family: | †Helcionellidae | 
| Genus: | †Mackinnonia Runnegar 1980  | 
| Species | |
  | |
Mackinnonia is a genus of small shelly fossil comprising straight or slightly coiled shells of the helcionelloid type.[1] The outer surface of their shell is smooth, whereas the inner surface has a net-like ridges.[1] They are known from late Early Cambrian rocks across North America and Greenland.[1]
References
    This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.