This is a very rare Trilobite couple from Siberia.
Please spend special attention to the fine cephalic structures of the smaller trilobite, the Hatangia.
You can see very clearly the "genal caeca" that is interpreted as a special additional lymph vessel lung organ.

The larger Trilobite, the Proasaphiscus rigidus is one of the most rare and remarkable trilobites from this locality.
Both trilobites are show a very detailed preservation of the shell.

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