This Deanaspis goldfussi from the Czech Letná Formation shows very nice the moulting mode of Trinucleid Trilobites.
The on the rostral plate attached duplication of the Sieve fringe that also caring the genal spines is thrown up side down behind the trilobite.
This moulting mode is simiair to the Salterian mode of Phacopids.
Phacopid Trilobites also don’t have a functional facial suture.
As little a extra has this piece a other complete specimen of Deanaspis goldfussi on the back of the plate.

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