Fossilised Acrosalenia hemicidaroides sea urchins with spines and stone lily (isocrinus sp.) found in Vosges, France. The fossil dates from 168 million years, during the Bajocian age of the Middle Triassic. The preservation of the sea urchins with their spines is exceptional, since they come off as soon as the animal dies. The analysis of the outcrop shows that the stratum with the sea urchins is surmounted by a sand dune several meters thick. We can assume that a hydraulic dune quickly buried the living sea urchins, making this exceptional preservation possible.