''Heteractis aurora'' is a

species In biology, a species is the basic unit of Taxonomy (biology), 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 ...

of sea anemone in the

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

Stichodactylidae Stichodactylidae is a family of sea anemones that contains the genera ''Stichodactyla'' (carpet anemones) and ''Heteractis''. These sea anemones exclusively reside within the shallow waters of the tropical Indo-Pacific area and are in the main ...

Taxonomy

Common names for ''H. aurora'' include beaded sea anemone, aurora host anemone, sand anemone, carpet anemone, flat anemone, corn anemone, Ritteri anemone, saddle tip anemone, adhesive sea anemone, and the white beaded anemone.

Description

Both the tentacles and oral disc of ''H. aurora'' are brown or purplish. The tentacles reach 50 mm in length, may be sticky when touched, and can have tips of a magenta colouration. The longer tentacles contain swellings. These appear on only on a single side, or almost entirely surrounding the tentacle, giving the appearance of beads on a string. A maximum of 20 such swellings may occur on any single tentacle. This species has a broad, flattened oral disc reaching 250 mm wide, and may have white or brown markings that radiate from the centre, and even continue up and along the tentacles.

Distribution and habitat

''H. aurora'' occurs in

Micronesia Micronesia (, ) is a subregion of Oceania, consisting of about 2,000 small islands in the western Pacific Ocean. It has a close shared cultural history with three other island regions: the Philippines to the west, Polynesia to the east, and ...

as well as in

Melanesia Melanesia (, ) is a subregion of Oceania in the southwestern Pacific Ocean. It extends from Indonesia's New Guinea in the west to Fiji in the east, and includes the Arafura Sea. The region includes the four independent countries of Fiji, ...

East Africa East Africa, Eastern Africa, or East of Africa, is the eastern subregion of the African continent. In the United Nations Statistics Division scheme of geographic regions, 10-11-(16*) territories make up Eastern Africa: Due to the histori ...

. It is also present in the

Red Sea The Red Sea ( ar, البحر الأحمر - بحر القلزم, translit=Modern: al-Baḥr al-ʾAḥmar, Medieval: Baḥr al-Qulzum; or ; Coptic: ⲫⲓⲟⲙ ⲛ̀ϩⲁϩ ''Phiom Enhah'' or ⲫⲓⲟⲙ ⲛ̀ϣⲁⲣⲓ ''Phiom ǹšari''; ...

, and in Australia to the

Ryukyu Islands The , also known as the or the , are a chain of Japanese islands that stretch southwest from Kyushu to Taiwan: the Ōsumi, Tokara, Amami, Okinawa, and Sakishima Islands (further divided into the Miyako and Yaeyama Islands), with Yona ...

. This species lives among coral, and along rocky reef edges and on slopes, normally in areas with strong currents. They attach themselves to a surface, and remain partially buried in sediment or sand, When threatened, they may retract entirely out of view into the substrate.

Ecology

''H. aurora'' hosts 7 species of anemonefish as symbionts: * ''

Amphiprion akindynos ''Amphiprion akindynos'', the Barrier Reef anemonefish, is a species of anemonefish that is principally found in the Great Barrier Reef of Australia, but also in nearby locations in the Western Pacific. The species name 'akindynos' is Greek, m ...

'' – Barrier reef anemonefish * ''A. allardi'' – Allard's anemonefish * ''A. bicinctus'' – Two-band anemonefish * ''A. clarkii'' - Clark's anemonefish * ''A. chrysogaster'' - Mauritian anemonefish * ''A. chrysopterus'' – Orange-fin anemonefish * ''A. tricinctus'' – Three-band anemonefish The relationship between anemonefish and their host sea anemones is highly nested in structure. With 7 species of hosted anemonefish, ''H. aurora'' is a generalist anemone, however it is considered a nursery anemone as, for reasons unknown, sexually mature fish are rarely hosted by ''H. aurora''. A number of other species are associated with ''H. aurora'', however the relationship is

commensal Commensalism is a long-term biological interaction ( symbiosis) in which members of one species gain benefits while those of the other species neither benefit nor are harmed. This is in contrast with mutualism, in which both organisms benefit fr ...

rather than mutual as the anemone does not appear to benefit from the association. These species are *

porcelain crab Porcelain crabs are decapod crustaceans in the widespread family Porcellanidae, which superficially resemble true crabs. They have flattened bodies as an adaptation for living in rock crevices. They are delicate, readily losing limbs when attac ...

s * Shrimp from the Periclimenes genus * Threespot dascyllus

Gallery

Image:Beaded Sea Anenome with shrimp.JPG, ''H. aurora'' with shrimp & anemonefish Image:Heteractis aurora timor.jpg, ''Amphiprion clarkii'' (Clark's anemonefish) with ''H. aurora'',

Timor Timor is an island at the southern end of Maritime Southeast Asia, in the north of the Timor Sea. The island is divided between the sovereign states of East Timor on the eastern part and Indonesia on the western part. The Indonesian part, al ...

Image:Heteractis aurora, Panglao.jpg, ''H. aurora'',

Panglao Island Panglao is an island in the north Bohol Sea, located in the Central Visayas region of the Visayas island group, in the south-central Philippines. Geography The island has an area of . It is within Bohol Province, and comprises two municipali ...

Image:Heteractis aurora.jpg, Crab & anemonefish with ''H. aurora'' Image:Clark's Anemonefish (Amphiprion clarkii) in Beaded Sea Anemone (Heteractis aurora) (8455438417).jpg, ''Amphiprion clarkii'' (Clark's anemonefish) in ''H. aurora''

References

External links

* {{Taxonbar, from=Q1528660 Stichodactylidae Animals described in 1833 Taxa named by Jean René Constant Quoy Taxa named by Joseph Paul Gaimard Cnidarians of the Indian Ocean Cnidarians of the Pacific Ocean