| Coscinasterias muricata | |
|---|---|
 | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Echinodermata |
| Class: | Asteroidea |
| Order: | Forcipulatida |
| Family: | Asteriidae |
| Genus: | Coscinasterias |
| Species: | C. muricata |
| Binomial name | |
| Coscinasterias muricata | |
Coscinasterias muricata is a species of starfish in the family Asteriidae. It is a large 11-armed starfish and occurs in shallow waters in the temperate western Indo-Pacific region. [1]
C. muricata is the largest starfish in southern Australia and can reach a diameter of 50 cm (20 in). It has seven to fourteen arms, with eleven being the commonest number. The aboral (upper) surface of the arms has longitudinal rows of short spines along the surface and margins and the oral (lower) surface has two rows of tube feet. The colour is orange mottled with shades of blue, green, grey and reddish-brown. [2] This starfish is prone to shedding its arms, making it asymmetric until new arms have grown. [3]
C. muricata is native to temperate parts of the western Indo-Pacific region. Its range extends in Australia from Houtman Abrolhos in Western Australia to southern Australia, Tasmania and eastern Australia as far north as Port Denison in Queensland. It is also found in New Zealand, Lord Howe Island and Norfolk Island. [2] It is common around southern Australia and New Zealand where it is found on rocks, under boulders and in sandy habitats to depths of about 150 m (500 ft). [4]
In sheltered baylets in Australia, the tunicate Pyura stolonifera can dominate the shallow seabed to the exclusion of other sessile organisms. This provides suitable habitat for filter feeders such as sea cucumbers, brittle stars, and bivalve molluscs, and among them can be found carnivorous starfish such as C. muricata, a specialist feeder on bivalves. [4] It is often to be found on mussel beds, as well as eating crabs and scavenging for carrion. [3]
This starfish can reproduce by binary fission; a groove appears on the surface of the disc and the two halves of the starfish pull apart from each other. [3] Each part will then regenerate its missing tissues. This is a form of asexual reproduction, and smaller individuals often divide in this way, while larger individuals have an extended breeding season, releasing sperm and eggs into the sea during spring and summer. The larvae are planktonic, and when sufficiently developed, settle onto the seabed in coralline algae habitats. [3]
An echinoderm is any member of the phylum Echinodermata of marine animals. The adults are recognizable by their radial symmetry, and include starfish, sea urchins, sand dollars, and sea cucumbers, as well as the sea lilies or "stone lilies". Adult echinoderms are found on the sea bed at every ocean depth, from the intertidal zone to the abyssal zone. The phylum contains about 7000 living species, making it the second-largest grouping of deuterostomes, after the chordates. Echinoderms are the largest phylum that has no freshwater or terrestrial members.
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 1,500 species of starfish occur on the seabed in all the world's oceans, from the tropics to frigid polar waters. They are found from the intertidal zone down to abyssal depths, 6,000 m (20,000 ft) below the surface.
The Echinasteridae are a family of starfish in the monotypic order Spinulosida. The family includes eight genera and about 133 species found on the seabed in various habitats around the world.
Isocrinida is an order of sea lilies which contains four extant families.
Ophiothrix angulata, the angular brittle star, is a species of marine invertebrate in the order Ophiurida. It is found in the warm waters of the western Atlantic Ocean, the Caribbean Sea and the Gulf of Mexico.
Astrobrachion constrictum is a basket star in the family Euryalidae. It is mostly found at depths of between 50 and 180 m, but around the coast of New Zealand it occurs in shallow waters, in association with the black coral Antipathella fiordensis.
Astrobrachion adhaerens is a basket star in the Euryalidae family. Along with A. constrictum, it is one of only two species in the genus Astrobrachion. Both species live in association with soft corals in moderately deep water. It is endemic to the west, north and east coasts of Australia, the Kermadec Islands and Lord Howe Island.
Asterodiscides truncatus, the firebrick starfish, is a species of five-armed starfish in the family Asterodiscididae. It is native to eastern and southern Australia, the Norfolk Ridge and the Kermadec Islands of New Zealand.
Echinaster luzonicus, the Luzon sea star, is a species of starfish in the family Echinasteridae, found in shallow parts of the western Indo-Pacific region. It sometimes lives symbiotically with a copepod or a comb jelly, and is prone to shed its arms, which then regenerate into new individuals.
Stichopus herrmanni, or Herrmann's sea cucumber, is a species of holothuroidean echinoderm in the family Stichopodidae. It is found in the tropical, western Indo-Pacific Ocean, at depths down to 20 m (66 ft). This and several other species are known as curryfish and are harvested commercially; it is called gama in Indonesia.
Endoxocrinus parrae is a species of stalked crinoids of the family Isselicrinidae. It is the most commonly found isocrinine species in west Atlantic Ocean.
Promachocrinus is a genus of free-swimming, stemless crinoids. It is a monotypic genus, and the only species in the genus is Promachocrinus kerguelensis. This is a coldwater crinoid which is found in the seas around Antarctica and surrounding island groups, including under the sea ice.
Hyocrinida is an order of sea lilies which contains a single extant family, Hyocrinidae.
Cyrtocrinida is an order of sea lilies which contains two suborders and three families.
Euretaster insignis, commonly known as the striking sea star, is a species of starfish in the family Pterasteridae found in the central west Pacific Ocean. It is one of only three species in the order Velatida to be found in shallow water in the tropics. The young are brooded in a cavity underneath a "supradorsal" membrane.
Aporometra wilsoni is a marine invertebrate, a species of crinoid or feather star in the family Aporometridae. It is found in shallow water around the coasts of southern Australia.
Aporometridae is a monotypic family of crinoids, the only genus being Aporometra, which contains three species, all endemic to the seas around Australia.
Notocrinidae is a monotypic family of crinoids, the only genus being Notocrinus, which contains two species, both endemic to the seas around Antarctica.
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.
Maria Byrne is professor of marine and developmental biology at the University of Sydney and a member of the Sydney Environment Institute. She spent 12 years as director of the university's research station on One Tree Island.