''Culcita novaeguineae'' (common name, cushion star) is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

starfish 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 ...

. It has short arms and an inflated appearance and resembles a

pentagon In geometry, a pentagon (from the Greek πέντε ''pente'' meaning ''five'' and γωνία ''gonia'' meaning ''angle'') is any five-sided polygon or 5-gon. The sum of the internal angles in a simple pentagon is 540°. A pentagon may be simpl ...

pincushion A pincushion (or pin cushion) is a small, stuffed cushion, typically across, which is used in sewing to store pins or needles with their heads protruding to take hold of them easily, collect them, and keep them organized. Pincushions are typic ...

. It is variable in colour and can be found in tropical warm waters in the

Indo-Pacific The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...

Taxonomy

''C. novaeguineae'' has numerous synonyms, at least in part because it has a "goniasterid" phase; the juveniles exhibit little resemblance to the mature form, and gradually change in

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines *Morphology (archaeology), study of the shapes or forms of artifacts *Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies, ...

as they grow. A number of different "species" were described in the literature before they were found to be different developmental stages of the same species. Some were even considered to be in a different

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

, the

Goniasteridae Goniasteridae (the biscuit stars) constitute the largest family of sea stars, included in the order Valvatida. They are mostly deep-dwelling species, but the family also include several colorful shallow tropical species. Description Goniast ...

, rather than in the correct family,

Oreasteridae The Oreasteridae are a family of sea stars in the class Asteroidea. Description and characteristics This family contains many species of regular starfishes with usually 5 arms around a stiff, convex and often brightly colored body. Whereas som ...

.The Cushion star ''Culcita novaeguineae'': An exercise in growth-related taxonomic confusion!
Echinoblog. Retrieved 2012-01-20.

Description

A mature ''C. novaeguineae'' is pentagonal to subglobose in shape with an inflated appearance and much-abbreviated arms. It can grow to a diameter of . Rows of tube feet are on the underside, and it has a central mouth. The colour is very variable and includes a mottling with darker and lighter shades of fawn, brown, orange, yellow and green.
SeaDB. Retrieved 2012-01-20. The armoured body wall is made of calcareous

ossicles The ossicles (also called auditory ossicles) are three bones in either middle ear that are among the smallest bones in the human body. They serve to transmit sounds from the air to the fluid-filled labyrinth (cochlea). The absence of the auditory ...

which are supported internally by pillars which buttress the

ambulacra Ambulacrum is an architectural word that denotes an atrium, courtyard, or parvise in front of a basilica or church that is surrounded by arcades or colonnades, or trees, and which often contains a fountain A fountain, from the Latin "fon ...

. The armouring contains pits into which the

tube feet Tube feet (technically podia) are small active tubular projections on the oral face of an echinoderm, whether the arms of a starfish, or the undersides of sea urchins, sand dollars and sea cucumbers; they are more discreet though present on britt ...

can be retracted. The body cavity is filled with water. On the dorsal face, they can be covered with small conical tubercles, as well inside as outside of papular areas. Small cushion stars are very different in appearance. They are star-shaped, with five short, broad arms and a low profile. As they grow, the inter-arm areas fill in and expand relative to the tube-feet areas, and the arms get shorter relative to the disc which becomes inflated and more massive. Image:Reef0208.jpg, A young specimen, still rather flattened. Image:Culcita novaeguineae.JPG, A slightly older one. Image:CulcitanovguineaeJI1.jpg, Mature specimen. Image:Pin Cushion Seastar (Culcita novaeguineae) (7383827098).jpg, A very spiny specimen from Fiji. Image:Culcita novaeguineae.jpg, Oral face.

Distribution

''C. novaeguineae'' is found in the Indian and Pacific Oceans. Its range extends from

Madagascar Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa ...

and the

Seychelles Seychelles (, ; ), officially the Republic of Seychelles (french: link=no, République des Seychelles; Creole: ''La Repiblik Sesel''), is an archipelagic state consisting of 115 islands in the Indian Ocean. Its capital and largest city, V ...

to the

Philippines The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no), * bik, Republika kan Filipinas * ceb, Republika sa Pilipinas * cbk, República de Filipinas * hil, Republ ...

New Guinea New Guinea (; Hiri Motu Hiri Motu, also known as Police Motu, Pidgin Motu, or just Hiri, is a language of Papua New Guinea, which is spoken in surrounding areas of Port Moresby (Capital of Papua New Guinea). It is a simplified version of ...

(for which it is named),

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

and

Hawaii Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only stat ...

Biology

''C. novaeguineae'' feeds on

detritus In biology, detritus () is dead particulate organic material, as distinguished from dissolved organic material. Detritus typically includes the bodies or fragments of bodies of dead organisms, and fecal material. Detritus typically hosts commun ...

and small

invertebrate Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...

s, including

stony corals Scleractinia, also called stony corals or hard corals, are marine animals in the phylum Cnidaria that build themselves a hard skeleton. The individual animals are known as polyps and have a cylindrical body crowned by an oral disc in which a mo ...

. It can be kept in a

reef aquarium A reef aquarium or reef tank is a marine aquarium that prominently displays live corals and other marine invertebrates as well as fish that play a role in maintaining the tropical coral reef environment. A reef aquarium requires appropriately ...

of sufficient size stocked with suitable corals on which it can feed.

Ecology

A number of organisms live in or on ''C. novaeguineae''. The small shrimp ''

Periclimenes soror ''Zenopontonia soror'', the starfish shrimp or seastar shrimp, is a species of shrimp in the family Palaemonidae. It is found in shallow water in the tropical Indo-Pacific region. It lives in association with a starfish, often changing its colour ...

'' lives as a commensal hiding under the cushion star. ''Astroxynus culcitae'', ''Stellicola oreastriphilus'' and ''Stellicola parvulipes'' are

copepods Copepods (; meaning "oar-feet") are a group of small crustaceans found in nearly every freshwater and saltwater habitat. Some species are planktonic (inhabiting sea waters), some are benthic (living on the ocean floor), a number of species have p ...

which live parasitically on the outside of the cushion star. The star pearlfish (''

Carapus mourlani The star pearlfish, ''Carapus mourlani'', is a species of slender, ray-finned fish in the family Carapidae. It normally lives inside a starfish or a sea cucumber. Description The star pearlfish is a long, slim, silvery fish growing to a maximum ...

'') sometimes lives as a commensal inside the cushion star, working its way into the large body cavity through an ambulacral groove and emerging periodically to feed.When Fish Live in your Cloaca & How Anal Teeth are Important! The Pearlfish-Sea Cucumber Relationship
Echinoblog. Retrieved 2012-01-21.

Synonyms

*''Anthenea spinulosa'' (Gray, 1847) *''Culcita grex'' Müller & Troschel, 1842 *''Culcita pentagularis'' Gray, 1847 *''Culcita pentangularis'' Gray, 1847 *''Culcita pulverulenta'' Perrier, 1869 *''Goniaster multiporum'' Hoffman in Rowe, 1974 *''Goniaster sebae'' (Muller & Troschel, 1842) *''Goniodiscides sebae'' (Müller & Troschel, 1842) *''Goniodiscus sebae'' Müller & Troschel, 1842 *''Hippasteria philippinensis'' Domantay & Roxas, 1938 *''Hosia spinulosa'' Gray, 1847 *''Pentagonaster spinulosus'' (Gray, 1847) *''Randasia granulata'' Gray, 1847

References

External links

*

' * {{Taxonbar, from=Q1306833 Oreasteridae Animals described in 1842