''Goniobranchus annulatus'' 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 ...

sea slug Sea slug is a common name for some marine invertebrates with varying levels of resemblance to terrestrial slugs. Most creatures known as sea slugs are gastropods, i.e. they are sea snails (marine gastropod mollusks) that over evolutionary t ...

, a very colourful dorid

nudibranch Nudibranchs () are a group of soft-bodied marine gastropod molluscs which shed their shells after their larval stage. They are noted for their often extraordinary colours and striking forms, and they have been given colourful nicknames to matc ...

, a shell-less

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

mollusc Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is esti ...

in the family

Chromodorididae Chromodorididae, or chromodorids, are a taxonomic family of colourful, sea slugs; dorid nudibranchs, marine gastropod mollusks in the superfamily Doridoidea. “Chromodorid nudibranchs are among the most gorgeously coloured of all animals.” ...

.Bouchet, P. (2012)
''Goniobranchus annulatus''.
Accessed through: World Register of Marine Species on 2012-04-22

Description

''Goniobranchus annulatus'' is a large smooth pale-bodied nudibranch with many vivid yellow spots, though these may be absent in some individuals. It has one purple ring around the

gill A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are ...

s and another ring around the

rhinophore A rhinophore is one of a pair of chemosensory club-shaped, rod-shaped or ear-like structures which are the most prominent part of the external head anatomy in sea slugs, marine gastropod opisthobranch mollusks such as the nudibranchs, sea har ...

s. The mantle usually has a purple border. It may grow to 100mm in total length.King, D. & Fraser, V. 2001. ''More Reef Fishes and Nudibranchs'' Struik, Cape Town. The gills are triangular in cross-section.Rudman, W.B., 1999 (April 11
''Chromodoris annulata'' Eliot, 1904.
n/nowiki> Sea Slug Forum. Australian Museum, Sydney.

Distribution

This nudibranch was described from

Zanzibar Zanzibar (; ; ) is an insular semi-autonomous province which united with Tanganyika in 1964 to form the United Republic of Tanzania. It is an archipelago in the Indian Ocean, off the coast of the mainland, and consists of many small islands ...

. It occurs 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''; T ...

, the

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or ~19.8% of the water on Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by th ...

, from the East Coast of

South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countri ...

Thailand Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is bo ...

. It is a Lessepsian migrant and has recently invaded the

Mediterranean Sea The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the ea ...

, presumably through the

Suez Canal The Suez Canal ( arz, قَنَاةُ ٱلسُّوَيْسِ, ') is an artificial sea-level waterway in Egypt, connecting the Mediterranean Sea to the Red Sea through the Isthmus of Suez and dividing Africa and Asia. The long canal is a popular ...

.Daskos A. & Zenetos A., 2007
''Additions to the knowledge of alien Opisthobranchia of Greece.
Aquatic Invasions 2(3): 258-260'']

Watch

''Goniobranchus annulatus''
in the

Persian Gulf The Persian Gulf ( fa, خلیج فارس, translit=xalij-e fârs, lit=Gulf of Persis, Fars, ), sometimes called the ( ar, اَلْخَلِيْجُ ٱلْعَرَبِيُّ, Al-Khalīj al-ˁArabī), is a Mediterranean sea (oceanography), me ...

, Abu-Dhabi, 2008.

References

{{DEFAULTSORT:Goniobranchus annulatus Chromodorididae Gastropods described in 1904