Fossilised Crinoid Stems

The item for sale is up to 6 Crinoid pieces.  The pieces will weigh at least 10g in total.  The photo shows an example of some of the pieces we have in stock. 

Crinoids  are commonly known as sea lilies due to their "flower-like" appearance , though they are animals, not plants. 

Crinoid ecological morphology

Crinoids are echinoderms related to starfish, sea urchins, and brittle stars. Like other members of their phylum they are spinny skinned, have a five-sided or pentaradial symmetry as adults and a calcium carbonate endoskeleton.

Although crinoids are the least understood of living echinoderms, their skeletal remains are among the most abundant and important of fossils. Crinoids were major carbonate producing organisms during the Paleozoic and Mesozoic. In fact, in many Paleozoic and Mesozoic settings entire carbonate shelves were composed predominantly of crinoidal remains. In such examples, the enormous volume of skeletal material controlled the sedimentary environment.

Evolution of Crinoidea

Crinoids derived in the Cambrian Period from pelmatozoan ancestors.

The first true Crinoids appeared during the Lower Ordovician. Following the global mass extinction at the Silurian boundary, they and underwent several major radiations at the early Devonian, Missisippian (peak) and Pennsylvanian. They almost became extinct at the end of Paleozoic Era in the Permian, but recovered to flourish again during the Mesozoic, in the Triassic and Jurassic (Lias, Dogger, Malm). Decreasing numbers in the Cretaceaous, fossil record of crinoidsis rare in the Tertiary. More than 6,000 fossil species, belonging to more than 800 genera, have been described. 

Today, approximately 600 living species are known; most free-living feather stars or comatulids living in the shallow seas.  About 80 species of stalked sea lilies are restricted to the deeper water of today`s ocean.