Crinozoa

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Crinozoa
Temporal range: Cambrian - Recent
Crinoid on the reef of Batu Moncho Island.JPG
Crinoid on the reef of Batu Moncho Island, Indonesia
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Echinodermata
Subphylum: Crinozoa
Matsumoto 1929
Classes

Crinozoa is a subphylum of mostly sessile echinoderms, of which the crinoids, or sea lilies and feather stars, are the only extant members. [1] [2] Crinozoans have an extremely extensive fossil history, which may or may not extend into the Precambrian (provided the enigmatic Ediacaran Arkarua can be positively identified as an edrioasteroid).

Contents

Classes within Crinozoa

The classes currently contained within Crinozoa include Crinoidea and the extinct Paracrinoidea (Cystoidea, Edrioasteroidea, and Rhombifera). [2]

Regeneration

Since the Paleozoic, sea lilies, or crinoids, have been able to regenerate and undergo arm autotomy or the intentional amputation of a limb. The sea lily can regenerate all of its arms at once in addition to its entire crown. Their stalk's uppermost segment and the basal plates have the capacity to regenerate the entire crown. Nutrients and other components from the stalk, especially the upper 5 cm, are used in crown regeneration. [3]

See also

Related Research Articles

<span class="mw-page-title-main">Chordate</span> Phylum of animals having a dorsal nerve cord

A chordate is a deuterostomic animal belonging to the phylum Chordata. All chordates possess, at some point during their larval or adult stages, five distinctive physical characteristics (synapomorphies) that distinguish them from other taxa. These five synapomorphies are a notochord, a hollow dorsal nerve cord, an endostyle or thyroid, pharyngeal slits, and a post-anal tail. The name "chordate" comes from the first of these synapomorphies, the notochord, which plays a significant role in chordate body plan structuring and movements. Chordates are also bilaterally symmetric, have a coelom, possess a closed circulatory system, and exhibit metameric segmentation.

<span class="mw-page-title-main">Echinoderm</span> Exclusively marine phylum of animals with generally 5-point radial symmetry

An echinoderm is any deuterostomal animal of the phylum Echinodermata, which includes starfish, brittle stars, sea urchins, sand dollars and sea cucumbers, as well as the sessile sea lilies or "stone lilies". While bilaterally symmetrical as larvae, as adults echinoderms are recognisable by their usually five-pointed radial symmetry, and are found on the sea bed at every ocean depth from the intertidal zone to the abyssal zone. The phylum contains about 7,600 living species, making it the second-largest group of deuterostomes after the chordates, as well as the largest marine-only phylum. The first definitive echinoderms appeared near the start of the Cambrian.

<span class="mw-page-title-main">Crinoid</span> Class of echinoderms

Crinoids are marine invertebrates that make up the class Crinoidea. Crinoids that remain attached to the sea floor by a stalk in their adult form are commonly called sea lilies, while the unstalked forms, called feather stars or comatulids, are members of the largest crinoid order, Comatulida. Crinoids are echinoderms in the phylum Echinodermata, which also includes the starfish, brittle stars, sea urchins and sea cucumbers. They live in both shallow water and in depths as great as 9,000 meters (30,000 ft).

<span class="mw-page-title-main">Sea urchin</span> Class of marine invertebrates

Sea urchins or urchins are typically spiny, globular animals, echinoderms in the class Echinoidea. About 950 species live on the seabed, inhabiting all oceans and depth zones from the intertidal to 5,000 metres. Their tests are round and spiny, typically from 3 to 10 cm across. Sea urchins move slowly, crawling with their tube feet, and sometimes pushing themselves with their spines. They feed primarily on algae but also eat slow-moving or sessile animals. Their predators include sea otters, starfish, wolf eels, and triggerfish.

<span class="mw-page-title-main">Starfish</span> Class of echinoderms, marine animal

Starfish or sea stars are star-shaped echinoderms belonging to the class Asteroidea. Common usage frequently finds these names being also applied to ophiuroids, which are correctly referred to as brittle stars or basket stars. Starfish are also known as asteroids due to being in the class Asteroidea. About 1,900 species of starfish live on the seabed in all the world's oceans, from warm, tropical zones to frigid, polar regions. They are found from the intertidal zone down to abyssal depths, at 6,000 m (20,000 ft) below the surface.

<i>Gogia</i> Extinct genus of marine invertebrates

Gogia is a genus of primitive eocrinoid blastozoan from the early to middle Cambrian.

<span class="mw-page-title-main">Stylophora</span> Extinct group of marine invertebrates

The stylophorans are an extinct, possibly polyphyletic group allied to the Paleozoic Era echinoderms, comprising the prehistoric cornutes and mitrates. It is synonymous with the subphylum Calcichordata. Their unusual appearances have led to a variety of very different reconstructions of their anatomy, how they lived, and their relationships to other organisms.

<span class="mw-page-title-main">Taxonomy of commonly fossilised invertebrates</span>

The taxonomy of commonly fossilized invertebrates combines both traditional and modern paleozoological terminology. This article compiles various invertebrate taxa in the fossil record, ranging from protists to arthropods. This includes groups that are significant in paleontological contexts, abundant in the fossil record, or have a high proportion of extinct species. Special notations are explained below:

<span class="mw-page-title-main">Eleutherozoa</span> Proposed group of marine invertebrates

Eleutherozoa is a proposed subphylum of echinoderms. They are mobile animals with the mouth directed towards the substrate. They usually have a madreporite, tube feet, and moveable spines of some sort. It includes all living echinoderms except for crinoids.

<span class="mw-page-title-main">Marine invertebrates</span> Marine animals without a vertebral column

Marine invertebrates are the invertebrates that live in marine habitats. Invertebrate is a blanket term that includes all animals apart from the vertebrate members of the chordate phylum. Invertebrates lack a vertebral column, and some have evolved a shell or a hard exoskeleton. As on land and in the air, marine invertebrates have a large variety of body plans, and have been categorised into over 30 phyla. They make up most of the macroscopic life in the oceans.

<i>Pentremites</i> Extinct genus of marine invertebrates

Pentremites is an extinct genus of blastoid echinoderm belonging to the family Pentremitidae.

<span class="mw-page-title-main">Deuterostome</span> Superphylum of bilateral animals

Deuterostomes are bilaterian animals of the superphylum Deuterostomia, typically characterized by their anus forming before the mouth during embryonic development. Deuterostomia is further divided into 4 phyla: Chordata, Echinodermata, Hemichordata, and the extinct Vetulicolia known from Cambrian fossils. The extinct clade Cambroernida is also thought to be a member of Deuterostomia.

<span class="mw-page-title-main">Homalozoa</span> Extinct historic group of marine invertebrates

Homalozoa is an obsolete extinct subphylum of Paleozoic era echinoderms, prehistoric marine invertebrates. They are also referred to as carpoids.

Pelmatozoa was once a clade of Phylum Echinodermata. It included stalked and sedentary echinoderms. The main class of Pelmatozoa were the Crinoidea which includes sea lily and feather star.

<span class="mw-page-title-main">Comatulida</span> Order of crinoids

Comatulida is an order of crinoids. Members of this order are known as feather stars and mostly do not have a stalk as adults. The oral surface with the mouth is facing upwards and is surrounded by five, often divided rays with feathery pinnules. Comatulids live on the seabed and on reefs in tropical and temperate waters.

<i>Metacrinus rotundus</i> Species of crinoid

Metacrinus rotundus, the Japanese sea lily, is a species of stalked crinoid in the family Isselicrinidae. It is a species found off the west coast of Japan, near the edge of the continental shelf at a depth of around 100 to 150 metres deep. This is the shallowest-living species among the extant stalked crinoids.

<i>Cenocrinus</i> Genus of crinoids

Cenocrinus is a monotypic genus of stalked crinoids in the family Isselicrinidae. The great West Indian sea lily is the only species in the genus and is found in deep waters in the Caribbean Sea and Gulf of Mexico.

<i>Florometra serratissima</i> Species of crinoid

Florometra serratissima is a species of crinoid or feather star in the family Antedonidae. It is found off the Pacific coast of North America, usually in deep water.

<i>Endoxocrinus parrae</i> Species of crinoid

Endoxocrinus parrae is a species of stalked crinoids of the family Isselicrinidae. It is the most commonly found isocrinine species in west Atlantic Ocean.

<i>Notocrinus virilis</i> Species of crinoid

Notocrinus virilis is a marine invertebrate, a species of crinoid or feather star in the family Notocrinidae. It is found in deep water in the Southern Ocean around the coasts of Antarctica and adjacent islands. A sea snail sometimes parasitizes it.

References

  1. Newton, Alisa L.; Dennis, Michelle M. (2021-03-23), LaDouceur, Elise E.B. (ed.), "Echinodermata", Invertebrate Histology (1 ed.), Wiley, pp. 1–18, doi:10.1002/9781119507697.ch1, ISBN   978-1-119-50765-9, S2CID   261009894 , retrieved 2023-08-04
  2. 1 2 "WoRMS - World Register of Marine Species - Crinozoa". www.marinespecies.org. Retrieved 2023-09-16.
  3. Amemiya, Shonan; Oji, Tatsuo (June 1992). "Regeneration in sea lilies". Nature. 357 (6379): 546-547. Bibcode:1992Natur.357..546A. doi:10.1038/357546a0. ISSN   1476-4687.