Crinoids Fossil range: Ordovician - Recent
A Passion Flower feather star (Ptilometra australis)
Scientific classification
Kingdom: Animalia Phylum: Echinodermata Class: Crinoidea Miller, 1821
Subclasses
Articulata (540 species) Cladida (extinct) Flexibilia (extinct) Camerata (extinct) Disparida (extinct) The Ordovician period is the second of the six (seven in North America) periods of the Paleozoic era. ... Download high resolution version (1600x1200, 225 KB) Wikipedia does not have an article with this exact name. ... Scientific classification or biological classification is a method by which biologists group and categorize species of organisms. ... Animalia redirects here. ... Classes Asteroidea Concentricycloidea Crinoidea Echinoidea Holothuroidea Ophiuroidea Echinoderms (Echinodermata) is a phylum of marine animals found in the ocean at all depths. ... For other uses, see Miller (disambiguation). ... Orders Bourgeticrinida Comatulida Articulata are the only extant subclass of the class Crinoidea. ...

Crinoids, also known as "sea lilies" or "feather-stars", are marine animals that make up the class Crinoidea of the echinoderms (phylum Echinodermata). They live both in shallow water and in depths as great as 6000 meters. Crinoids are characterized by a mouth on the top surface that is surrounded by feeding arms. They have a U-shaped gut, and their anus is located next to the mouth. Although the basic echinoderm pattern of five-fold symmetry can be recognized, most crinoids have many more than five arms. Crinoids usually have a stem used to attach themselves to a substrate, but many live attached only as juveniles and become free-swimming as adults. There are only a few hundred known modern forms, but crinoids were much more numerous both in species and numbers in the past. Some thick limestone beds dating to the mid- to late-Paleozoic are entirely made up of disarticulated crinoid fragments. Classes  ?Helicoplacoidea †  ?Arkarua †  ?Homalozoa † Eleutherozoa Asteroidea (1,800 species) Concentricycloidea (2 species) Echinoidea (1,000 species) Holothuroidea (1,000 species) Ophiuroidea (1,500+ species) Pelmatozoa Crinoidea (540+ species) Edrioasteroidea† Blastoidea † Cystoidea † Eocrinoidea † † = extinct Echinoderms (Phylum Echinodermata, from the Greek for spiny skin) are a phylum of marine animals found at... Stream substrate (sediment) is the material that rests at the bottom of a stream. ... This article or section does not cite any references or sources. ... The Paleozoic Era (from the Greek palaio, old and zoion, animals, meaning ancient life) is the earliest of three geologic eras of the Phanerozoic eon. ...

Button-like, fossilized pieces of crinoid stem from Ordovician limestone of Batavia, Ohio (USA)

fossilized crinoid stems Image copyleft: Image taken by me, released under GFDL Pollinator 05:00, Aug 23, 2004 (UTC) ( ) File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... fossilized crinoid stems Image copyleft: Image taken by me, released under GFDL Pollinator 05:00, Aug 23, 2004 (UTC) ( ) File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... The Ordovician period is the second of the six (seven in North America) periods of the Paleozoic era. ... Batavia is a village located in Clermont County, Ohio. ... Official language(s) None Capital Columbus Largest city Columbus Largest metro area Cleveland Area  Ranked 34th  - Total 44,825 sq mi (116,096 km²)  - Width 220 miles (355 km)  - Length 220 miles (355 km)  - % water 8. ...

Evolution

The earliest known crinoids come from the Ordovician. They are thought to have evolved from primitive echinoderms known as Eocystoids. Confusingly, another early group of echinoderms were also the Eocrinoids, but that group is currently thought to be an ancestor of blastoids rather than of crinoids. Some fossil crinoids, such as Pentacrinites, seem to have lived attached to floating driftwood and complete colonies are often found. Sometimes this driftwood would become waterlogged and sink to the bottom, taking the attached crinoids with it. The stem of Pentacrinites can be several metres long. Modern relatives of Pentacrinites live in gentle currents attached to rocks by the end of their stem, which is fairly short. The Ordovician period is the second of the six (seven in North America) periods of the Paleozoic era. ... Blastoids (Blastoidea) are an extinct type of stemmed echinoderm. ...

Drawing of the calyx of the crinoid Pentacrinites

Feather Star found at the Similan Islands, off the coast of Thailand.

Most modern crinoids are free-swimming and lack a stem. Examples of free-swimming crinoid fossils include Marsupitsa, Saccocoma and Uintacrinus. Many fossils of free-swimming crinoids (such as Pterocoma) are found in the Jurassic-dated Solnhofen limestone of Solnhofen in Germany, and the Cretaceous-dated Niobrara chalk of Kansas contains large numbers of Uintacrinus. Drawing of the calyx of the crinoid Pentacrinites, scanned from a copyright free source. ... Drawing of the calyx of the crinoid Pentacrinites, scanned from a copyright free source. ... Image File history File linksMetadata No higher resolution available. ... Image File history File linksMetadata No higher resolution available. ... The Jurassic Period is a major unit of the geologic timescale that extends from about 199. ... A brittle star fossil from Solnhofen limestone. ... Solnhofen is a town in the district of Weißenburg-Gunzenhausen in the region of Franconia in the Land of Bavaria in Germany. ... The Cretaceous Period is one of the major divisions of the geologic timescale, reaching from the end of the Jurassic Period (i. ... This article needs additional references or sources to facilitate its verification. ...

In 2005, a stalked crinoid was recorded pulling itself along the sea floor off the Grand Bahama Island. While it has been known that stalked crinoids move, prior to this recording the fastest motion of a crinoid was 0.6 meters/hour (2 ft/h). The 2005 recording showed a crinoid moving at 140 meters/hour (460 ft/h).^[1] Grand Bahama from space, June 1998 Grand Bahama is one of the northernmost of the islands of the Bahamas, and the closest major island to the United States, lying just 55 mi (90 km) off the coast of the state of Florida. ...

Crinoids comprise three basic sections; the Stem, Calyx, and the Arms. The stem is composed of highly porous ossicles which are filled with muscular tissue. The Calyx contains the crinoid's digestive and reproductive organs, and the mouth is located at the top of the dorsal cup, while the anus is located peripheral to it. The brachials(arms) display pentameral symmetry and comprise smaller ossicles than the stem and are equipped with cirri which facilitate feeding by moving the the organic media down the arm and into the mouth. It has been suggested that this article or section be merged with mouth (human). ... For the famous Italian cellist, see: Giovanni Battista Cirri For the clouds, see: Cilium ...

Crinoids reproduce sexually by the males releasing their sperm and the females releasing their eggs into the current where they will develop into a bottom-dwelling non-feeding larval stage and then eventually grow a stalk(in the stalked crinoids), and within 10 to 16 months will be able to reproduce. In some cases the female of the species has been known to temporarly brood the larva. Different types of sperm cells: A) spermatozoon (motile), B) spermatium (non-motile), C) fertilization tube with sperm nuclei For other uses, see Sperm (disambiguation). ... A human ovum Sperm cells attempting to fertilize an ovum An ovum (plural ova) is a haploid female reproductive cell or gamete. ... Look up Brood in Wiktionary, the free dictionary. ... A larval insect A larva (Latin; plural larvae) is a juvenile form of animal with indirect development, undergoing metamorphosis (for example, insects or amphibians). ...

The crinoids have had an eventful geologic history. Once evolved, they soon spread to a variety of marine habitats. The group as a whole suffered a major crisis during the Permian period when most of the crinoid forms of the Palaeozoic era died out, with a few surviving into the Triassic period. During the Mesozoic era there was another great radiation of the crinoids with more modern forms possessing flexible arms becoming widespread. The Permian is a geologic period that extends from about 299. ... The Palaeozoic is a major division of the geologic timescale, one of four geologic eras. ... The Triassic is a geologic period that extends from about 251 ± 0. ... The Mesozoic Era is one of three geologic eras of the Phanerozoic eon. ...

Fossil crinoid stems from Arkansas.

The long and varied geological history of the crinoids demonstrates how well the echinoderms have adapted to filter-feeding. The fossils of other stalked filter-feeding echinoderms, such as blastoids, are also found in the rocks of the Palaeozoic era. These extinct groups can exceed the crinoids in both numbers and variety in certain horizons. They were evidently competing with the crinoids on an equal basis. However, none of these others survived the crisis at the end of the Permian period. Download high resolution version (1841x1226, 561 KB) Wikipedia does not have an article with this exact name. ... Download high resolution version (1841x1226, 561 KB) Wikipedia does not have an article with this exact name. ... The Palaeozoic is a major division of the geologic timescale, one of four geologic eras. ...

An abundance of (stemmed) crinoids occurs in the rocks of the Silurian period in the United Kingdom and the eastern United States, the Devonian period of Kentucky, Michigan, Illinois, New York state and the Hunsrück Slates near Bundenbach in the Eifel region of Germany, the Carboniferous period of the United Kingdom, Belgium and Russia, the Mississippian period of Iowa, Indiana, and Alabama, the Pennsylvanian period of the mid-continental United States, the Permian period of the island of Timor, and the Triassic period of Germany. They are the state fossil of Missouri. Some prehistoric crinoids, like Solanocrinus, lacked stems. The Silurian is a major division of the geologic timescale that extends from the end of the Ordovician period, about 443. ... Artists illustration of a Devonian scene. ... Official language(s) English[1] Capital Frankfort Largest city Louisville Area  Ranked 37th  - Total 40,444 sq mi (104,749 km²)  - Width 140 miles (225 km)  - Length 379 miles (610 km)  - % water 1. ... Official language(s) None (English, de-facto) Capital Lansing Largest city Detroit Area  Ranked 11th  - Total 97,990 sq mi (253,793 km²)  - Width 239 miles (385 km)  - Length 491 miles (790 km)  - % water 41. ... Official language(s) English[1] Capital Springfield Largest city Chicago Largest metro area Chicago Area  Ranked 25th  - Total 57,918 sq mi (149,998 km²)  - Width 210 miles (340 km)  - Length 390 miles (629 km)  - % water 4. ... NY redirects here. ... The Hunsrück Slate (Hunsrückschiefer) is a Devonian Lagerstätte famous for exceptional preservation of a highly diverse fossil fauna assemblage. ... The Carboniferous is a major division of the geologic timescale that extends from the end of the Devonian period, about 359. ... This article is about the geologic period; for the North American culture, see Mississippian culture. ... This article is about the U.S. State. ... Official language(s) English Capital Indianapolis Largest city Indianapolis Area  Ranked 38th  - Total 36,418 sq mi (94,321 km²)  - Width 140 miles (225 km)  - Length 270 miles (435 km)  - % water 1. ... Official language(s) English Capital Montgomery Largest city Birmingham Area  Ranked 30th  - Total 52,419 sq mi (135,765 km²)  - Width 190 miles (306 km)  - Length 330 miles (531 km)  - % water 3. ... The Pennsylvanian is an epoch of the Carboniferous period lasting from roughly 325 Ma to 299 Ma (million years ago). ... Timor is an island at the south end of the Malay Archipelago, divided between the independent state of East Timor, and West Timor, part of the Indonesian province of East Nusa Tenggara with the surface of 11,883 sq mi (30,777 km²). The name is a variant of timur... Official language(s) English Capital Jefferson City Largest city Kansas City Largest metro area Greater St. ... Binomial name Solanocrinus thiollieri Solanocrinus thiollieri is an extinct species of crinoid from Jura, France (not to be confused with the Jurassic period). ...

Crinoids in pop culture

• The Pokémon Lileep and Cradily are based on crinoids (specifically, sea lilies).

The official Pokémon logo. ... Lileep , Lilyla in original Japanese language versions) are a fictional species found as a fossil in the Hoenn region of the Pokémon games. ... Cradily , Yuradle) is a fictional character from the Pokémon franchise. ...

References

October 6 is the 279th day of the year (280th in leap years). ... 2005 (MMV) was a common year starting on Saturday of the Gregorian calendar. ...

External links

• Tree of Life (source of taxonomic information on this page)
• Article and video of crinoid crawling
• On the Crinoid Genus Scyphocrinus and its Bulbous Root Camarocrinus by Frank Springer. 3 p., 74 p. illus., IX pl. (2 fold.) 33 cm. Washington: Smithsonian Institution, 1917
• American Silurian Crinoids by Frank Springer. iv, 239 p. 33 pl., 2 port. 32 cm. Washington: The Smithsonian Institution, 1926
• Introduction to the Crinoidea: Sea lilies and feather stars... ucmp.berleley.edu. Retrieved on February 7, 2007.