Trinucleus fimbriatus.
This is a rare species, Trinucleus fimbriatus, from the United Kingdom. A positive/negative pair specimen.
The entire body is preserved without compression or deformation. No repairs. Using a 10x loupe, the pits remaining on the cephalic fringe can be clearly observed.
Trilobites from the UK are diverse, have been collected and studied for a long time, and are popular among collectors, mainly in Europe and America.
Acquired at auction.