Here is a rare Bolivian trilobite of the species Plesiomalvinella pujravii from the Devonian Belén Formation  .
The trilobite offers a detailed preservation and is well presented in the center of the concretion. The calmonid trilobite genus Plesiomalvinella is characterized by its spectacular thorns and pustulation. That this specimen also shows nicely.
If fully stretched, would this Plesiomalvinella be about 56 mm long.
 

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