This is are three Agnostid trilobite from Utah of the species Peronopsis interstricta in a nice preservation. The smallees trilobite measures a little more than and a milimeter.
This small Agnostid is a early Meraspis Laval stage, between head and tail is no pleural segment. On this plate we have a good odontogenetic row of Agnostied on one single plate what is very rare to be seen.

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