Acastella sp.
Trilobite
Lower Silurian
Revesto Sbsvyte Formation
Kamyanets-Podolskiy Region, Kitajgorod (Kitaihorod), Ukraine

19mm trilobite on 51mm matrix.

Arthropod. Trilobite.

Acastella is a trilobite genus that lived during the Silurian and survived into the Devonian.  It is known from Europe and New Zealand but is uncommon wherever it occurs.

Interesting and affordable specimen.