Museum Crinoid Plate 2390mm in the longest dimension. This highly important museum standard plate is crammed with a colony group of fossil crinoids (crinoids are a class of the Crinoidea of echinoderms), relatives of starfish and sea urchins which appeared in the Cambrian period fossil record around 500 million years ago. The common nomenclature sea lilies or lily of the sea is a very apt descriptive name, flower like heads on long stems seemingly flow in the forgotten sea currents. The specimen crinoids fossilised on the original seabed which is a limestone. The rock bed extracted from the Western Sahara Desert of Morocco. The once extant marine colony are exceptionally well preserved on a monumental sized plate. This natural anomaly dramatically creates a display of prehistoric oceanic life from the Devonian era, some 420 to 380 million years ago. The specific classified type of genus is Scyphocrinites elegans.
The fossil crinoids are sometimes found attached to fossilised wood, charred like coal, the wood is often blackened. The wood or trunk is thought to be driftwood, flotsam of the ancient seas, a suspending traveller, the head or crown hanging into the depths sifting out nutrients. it is theorised when driftwood became waterlogged sinking to the bottom the crinoids went with it. Crinoids have been found in the fossil record to have had stems up to 40 metres in length and also found attached to the sea bed or rocks on the sea floor. The fossil community have differing thoughts as to whether the crinoids were pelagic or sedentary, however the facts above perhaps illustrates they were developing both lifestyles. Modern crinoids attach to rock pools to ocean floors and are an evolution of these prehistoric crinoids. The prehistoric crinoids are classed as neither plant nor animal so far, but a sub specie, in between both groups.
The quality, preservation, completeness and size makes this museum standard Crinoidea plate unique and highly desirable. Sea lilies (crinoids), were and still are exclusively a marine animal, a member of the Phylum echinodermata, sea lily originates from the Greek, Krinon, which translates to lily. These sea lilies persist today, some dwelling at great depths in our oceans up to six thousand metres, nearly four miles and also in shallow seas and coral reefs.
Anatomy. The three main parts of the Crinoids are…
The arms composed of an articulated series of ossicles (Pinnules), these are used in suspension for feeding and respiration. The gonads are also located in the arms, fertilisation takes place in open sea water during mass spawning.
The Calyx, the crown or aboral cup, These contain the vital organs of the animal.The Calyx is small when compared to the total mass, most of which is devoted to food collection. The mouth is located on the upper surface of the body.
The columned stem supported the Crinoid crown and together with the baluster root, possibly a floatation aid, may have also served as a means of attachment to the sea bed or other substrate such as driftwood, tree trunks, floating on the surface of the ocean. Crinoids have been discovered with roots attached to large chunks of what would have been wood.
A fine but much smaller plate originating from the same deposit field of Efourd in Morocco, but of smaller dimensions (only 1.60 metres) is on exhibit at the Musée des Confluences in Lyon.
The museum quality plate illustrated above, of monumental size, offers specimens of great clarity and well conserved, exhibiting soft grey pearly tint to the individuals, which delicately stand out against a pinkish-red matrix, exhibiting a fine and beautiful contrast.
To read more about the Crinoidea group, their anatomy, lifestyle, where they are found and how we excavate them follow this link to discover another world. Discover more about the Crinoidea family