''Echmatocrinus'' is a

Cambrian The Cambrian Period ( ; sometimes symbolized Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million years ag ...

animal which resembles a

crinoid Crinoids are marine animals that make up the Class (biology), class Crinoidea. Crinoids that are attached to the sea bottom by a stalk in their adult form are commonly called sea lilies, while the unstalked forms are called feather stars or coma ...

or an

octocoral Octocorallia (also known as Alcyonaria) is a class of Anthozoa comprising around 3,000 species of water-based organisms formed of colonial polyps with 8-fold symmetry. It includes the blue coral, soft corals, sea pens, and gorgonians (sea fans ...

. Its exact taxonomy is still a subject of debate. It is known only from the

Burgess shale The Burgess Shale is a fossil-bearing deposit exposed in the Canadian Rockies of British Columbia, Canada. It is famous for the exceptional preservation of the soft parts of its fossils. At old (middle Cambrian), it is one of the earliest fos ...

. 5 specimens of ''Echmatocrinus'' are known from the Greater

Phyllopod bed The Phyllopod bed, designated by USNM locality number 35k, is the most famous fossil-bearing member of the Burgess Shale fossil '' Lagerstätte''. It was quarried by Charles Walcott from 1911–1917 (and later named Walcott Quarry), and was ...

, where they comprise < 0.1% of the community. The creature was a little like an inverted cone, with a crown of seven to nine tentacles. Each tentacle was covered with small extensions. The cone itself was covered with irregularly arranged mineralised plates. The organisms lived a solitary lifestyle, although juveniles are sometimes attached to (or budding from) adults.

References

External links

Ausich, W. I. 1998a. Early phylogeny and subclass division of the Crinoidea (phylum Echinodermata). Journal of Paleontology 72 (3): 499–510. Ausich, W. I. 1998b. Origin of the Crinoidea. In Echinoderms: San Francisco (R. Mooi & M. Telford, eds.) pp. 127–132. A. A. Balkema: Rotterdam. Ausich, W. I. 1999. Origin of crinoids. In Echinoderm Research 1998 (M. D. Candia Carnevali & F. Bonasoro, eds.) pp. 237–242. A. A. Balkema: Rotterdam. Sprinkle, J., & R. C. Moore. 1978. Echmatocrinea. In Treatise on Invertebrate Paleontology pt. T. Echinodermata 2. Crinoidea (R. C. Moore & C. Teichert, eds.) vol. 2, pp. T405-T407. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas: Lawrence (Kansas). Burgess Shale fossils Enigmatic prehistoric animal genera Fossil taxa described in 1973 Cambrian genus extinctions {{Paleo-echinoderm-stub

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Further reading