This beautiful fossil plate is a large sampling of organisms from the genus Ascocystites. 470 million years ago, these creatures were rooted into the seafloor by their stems. Their close assemblage here likely indicated a mass mortality event, possibly due to a sudden change in their environment.

Though they may look like small squids, these creatures are actually members of the Eocrinoidea class, an echinoderm related to modern crinoids. The animals were Ordovician benthic organisms, living within the seabed and gathering food particles from the current with their arms.

The specimen has been beautifully prepared through acid etching, a process that helps extract the organic fossil prints from the carbonate matrix. It measures 14" on its longest side and ships with a certificate of authenticity as well as a fantastic black stand for display.

This is a wonderful one-of-a-kind fossil with fantastic detail. It makes for a great display piece in any collection and we are excited to offer it on the site!

During the Cambrian Explosion, the world’s oceans hosted a new abundance of life. Fish swam, trilobites crawled, and ammonites hunted, but not all creatures needed to be mobile to get a meal.

Ascocystites, a genus of the wider Eocrinoidea class, were rooted to the ocean floor by their holdfast, a root-like structure common in benthic creatures. Instead of hunting, Ascocystites relied on food particles in the water for nutrients. While other animals fought for dominance in the oceans above, this organism and its simple feeding strategy flourished well into the Middle Ordovician Period.

Ascocystites fossils are found mostly along the Mediterranean in Algeria, Morocco, France, and Portugal, across a geologic timeline of 70 million years. Like other Eocrinoids, these creatures were suspension feeders, with over 20 arms to catch drifting food particles. Their stalks were reinforced with a theca sheath of skeletal structures, giving the creatures the distinct shape left behind in their fossils. This skeleton also acted as natural armor, protecting Ascocystites against predation.

Ascocystites was discovered by Joachim Barrande, a French paleontologist who described a number of similar sea creatures during the nineteenth century. Barrande was an opponent of evolution, instead preferring Georges Cuvier’s catastrophism which saw the fossil record defined by global catastrophes like the Biblical flood. While Cuvier’s theory was incorrect, it did anticipate the idea of mass extinctions and their impact on the fossil record.

Catastrophism was an attractive theory in light of the dearth of fossils before the Cambrian explosion, but this gap can be explained by the dominance of soft-bodied life before the radiation.

Though Barrande did not know it, Ascocystites are proof of Darwin’s theory, a hard-bodied work of evolution that flourished during the Cambrian. Its simple feeding strategy allowed this Eocrinoid to thrive across all levels of the ocean floor for millions of years.