Belemnitella

Belemnitella is a genus of belemnite from the Late Cretaceous of Europe and North America. Belemnitella was a squidlike animal, probably related to the ancestors of modern squids and cuttlefish. The shell was internal. The rostrum or guard is found the most often and possesses a distinctive slit at its ventral surface and a ridge on the dorsal surface. The phragmocone (internal shell) has a small protoconch at its tip, and fit into the cavity and the guard. It also had septa and a ventral siphuncle (tube filled with living tissues running through chambers) within the phragmocone, projecting forward as a beak-like blade.

Belemnitella
Temporal range: 84.9–66.043 Ma
Belemnitella mucronata
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Order: †Belemnitida
Family: †Belemnitellidae
Genus: †Belemnitella
d'Orbigny, 1840
Species

It had growth layers like tree rings, seen within the cavity of the organism and when the cone is sectioned. The cone was light-brown and glassy in appearance. It is distributed widely in North America. A specimen of a belemnoid had been found in Germany, clearly preserving 10 tentacles as carbon films, showing that belemnoids are similar to squids. [1][2][3]

References
  1. Fossils (Smithsonian Handbooks) by David Ward (Page 163)
  2. National Audubon Society Field Guide to North American Fossils (Page 536)
  3. Neal L. Larson; Steven D. Jorgensen; Robert A. Farrar & Peter L. Larson (1997). Ammonites and the Other Cephalopods of the Pierre Seaway. Geoscience Press, Inc. p. 94. ISBN 0-945005-34-2.


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