Ceratosoma amoenum, or the clown nudibranch, is a species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of colorful dorid nudibranch

Nudibranch

A nudibranch is a member of what is now a taxonomic clade, and what was previously a suborder, of soft-bodied, marine gastropod mollusks which shed their shell after their larval stage. They are noted for their often extraordinary colors and striking forms...

, a sea slug

Slug

Slug is a common name that is normally applied to any gastropod mollusc that lacks a shell, has a very reduced shell, or has a small internal shell...

, a shell-less marine

Marine (ocean)

Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...

 gastropod mollusk in the family Chromodorididae

Chromodorididae

Chromodorididae are a taxonomic family of medium-sized to large, colorful, sea slugs; dorid nudibranchs in the superfamily Doridoidea. These are marine gastropod mollusks....

.

Following the gender rules of International Code of Zoological Nomenclature

International Code of Zoological Nomenclature

The International Code of Zoological Nomenclature is a widely accepted convention in zoology that rules the formal scientific naming of organisms treated as animals...

, the spelling of Ceratosoma amoena has been changed into Ceratosoma amoenum

Distribution

Ceratosoma amoenum is a common nudibranch found in the intertidal zone

Intertidal zone

The intertidal zone is the area that is above water at low tide and under water at high tide . This area can include many different types of habitats, with many types of animals like starfish, sea urchins, and some species of coral...

s of temperate southern Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

 and northern New Zealand

New Zealand

New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...

. There have also been a few reported sightings off the coast of southern Queensland

Queensland

Queensland is a state of Australia, occupying the north-eastern section of the mainland continent. It is bordered by the Northern Territory, South Australia and New South Wales to the west, south-west and south respectively. To the east, Queensland is bordered by the Coral Sea and Pacific Ocean...

.

Description

This species has a white body which is elaborately patterned with orange and purple spots especially on the dorsum. The size of the spots varies according to range, with those individuals in New Zealand having the largest. There is some variation in the patterning of this species.

The gills and rhinophores are crimson-white in color and both the rhinophore

Rhinophore

A rhinophore is one of a pair of club-shaped structures which are the most prominent part of the external head anatomy of a group of sea slugs, marine gastropod opisthobranch mollusks in the order Nudibranchia, the nudibranchs, specifically the dorid nudibranchs.- Etymology :The name relates to the...

s and the unbranched gill

Gill

A gill is a respiratory organ found in many aquatic organisms that extracts dissolved oxygen from water, afterward excreting carbon dioxide. The gills of some species such as hermit crabs have adapted to allow respiration on land provided they are kept moist...

s can be retracted into pockets. At the rear of the mantle there is a large concentration of mantle glands. This species reaches at least 60 mm in length.

Ecology

Ceratosoma amoenum is known to feed on sponges. It has been seen feeding on sponges from the genus Semitaspongia and the species Dysidea fragilis. It sequesters metabolite

Metabolite

Metabolites are the intermediates and products of metabolism. The term metabolite is usually restricted to small molecules. A primary metabolite is directly involved in normal growth, development, and reproduction. Alcohol is an example of a primary metabolite produced in large-scale by industrial...

s from its prey as a defense mechanism.

External links

• Ceratosoma amoenum at nudipixel