Shark Tooth

The teeth of sharks can be difficult to identify in isolation.  Those at the front of the jaw (anteriors) are often straight with an inflection in the lateral view.  The teeth at the side of the jaw (laterals) may be curved backwards in many species.   In reality, a tooth from one part of a shark’s jaw may look similar to a tooth from another part of the jaw of a different species.  There are also some species which have quite unique teeth.  This tooth is an anterior tooth from a Goblin Shark, Anatomadus species.  It can easily be confused with the teeth of Odontaspis species, the tiger shark.

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Phillipsia

To enable comparison of fossil material, it is often wise to cast specimens.  The casts can then be carried arround without the risk of damaging the original specimen.  This is an unusual fossil of the inside of a trilobite carapace, exposed for inspection.  It is Phillipsia gemmulifera from the carboniferous.

Griffithides

Derbyshire Limestone occasionally shows some interesting Carboniferous fossils.  This is an uncommon occurence of a trilobite pygideun of Griffithides species.

Fossil Tooth

There are a lot of fossil teeth out there, especially from large marine predators like sharks, which shed their teeth naturally, and marine reptiles which break their teeth on hard prey.  Most of the teeth are like this one, isolated and out of context.  I would call this an indeterminate fossil tooth, but some would call it plesiosaur, ichthyosaur, pterosaur, etc…  Who knows what it is from?

Rhamphorhynchus

Rhamphorhynchus was a long-tailed pterosaur from the Upper Jurassic.  This bone is the Humerus of the wing of Rhamphorhynchus Longiceps.  The original fossil humeri are embedded in shale and this represents a reconstruction of the whole bone based on the actual specimen.  This allows the bone to be handled and rotated for comparison with other specimens.

Unidentified Beetle

Today I have posted another Baltic Amber insect

This shows a very small ground beetle.

The form is not easily identifiable as there are thousands of such beetle species in the ecological woodland environment.  Expert study may reveal the species, but this is beyond my skills at present.

Probably an ant

Within this block of Baltic Amber is a small insect.  As the amber has not been polished, the form is difficult to resolve.  It looks like a small ant species.