Three-spot nudibranch

Last updated

Three-spot nudibranch
Aldisa trimaculata.jpg
Scientific classification
Kingdom:
Phylum:
Class:
(unranked):
Superfamily:
Family:
Genus:
Species:
A. trimaculata
Binomial name
Aldisa trimaculata
Gosliner in Millen & Gosliner, 1985

The three-spot nudibranch, scientific name Aldisa trimaculata, is a species of sea slug, a dorid nudibranch, a marine gastropod mollusc in the family Cadlinidae.

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 sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. While these definitions may seem adequate, when looked at more closely they represent problematic species concepts. For example, the boundaries between closely related species become unclear with hybridisation, in a species complex of hundreds of similar microspecies, and in a ring species. Also, among organisms that reproduce only asexually, the concept of a reproductive species breaks down, and each clone is potentially a microspecies.

Doridoidea superfamily of molluscs

Doridoidea, commonly known as dorid nudibranchs, are a taxonomic superfamily of medium to large, shell-less sea slugs, marine gastropod mollusks in the clade Doridacea, included in the clade Nudibranchia.

Nudibranch order of molluscs

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 match, such as "clown", "marigold", "splendid", "dancer", and "dragon". Currently, about 3,000 valid species of nudibranchs are known.

Contents

Distribution

This demersal species has so far only been found around the southern African coast, on both sides of the Cape Peninsula, in 10–30 m of water. It may possibly be endemic to that area. [1]

Demersal zone The part of the water column near to the seabed and the benthos

The demersal zone is the part of the sea or ocean consisting of the part of the water column near to the seabed and the benthos. The demersal zone is just above the benthic zone and forms a layer of the larger profundal zone.

Cape Peninsula Rocky peninsula in the Western Cape, South Africa

The Cape Peninsula is a generally rocky peninsula that juts out into the Atlantic Ocean at the south-western extremity of the African continent. At the southern end of the peninsula are Cape Point and the Cape of Good Hope. On the northern end is Table Mountain, overlooking Cape Town, South Africa. The peninsula is 52 km long from Mouille point in the north to Cape Point in the south.

Endemism ecological state of being unique to a defined geographic location or habitat

Endemism is the ecological state of a species being unique to a defined geographic location, such as an island, nation, country or other defined zone, or habitat type; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. The extreme opposite of endemism is cosmopolitan distribution. An alternative term for a species that is endemic is precinctive, which applies to species that are restricted to a defined geographical area.

Description

Two of the dotted spots of the three-spot nudibranch Aldisa trimaculata nov07.jpg
Two of the dotted spots of the three-spot nudibranch

The three-spot nudibranch is a tan-coloured dorid with a warty skin and three brown spots, which are themselves spotted with lighter patches. The animal has eight gills arranged around the anus and its rhinophores are perfoliate. It may reach a total length of 40 mm. [2]

Gill respiratory organ

A gill is a respiratory organ found in many aquatic organisms that extracts dissolved oxygen from water and excretes carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are kept moist. The microscopic structure of a gill presents a large surface area to the external environment. Branchia is the zoologists' name for gills.

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 (Nudibranchia), Sea Hares, (Aplysiomorpha) and sap-sucking sea slugs (Sacoglossa).

Ecology

This species feeds on sponges.

Related Research Articles

<i>Aldisa</i> genus of molluscs

Aldisa is a genus of sea slugs, dorid nudibranchs, marine gastropod molluscs in the family Cadlinidae.

Chocolate-chip nudibranch species of Gastropoda

The chocolate-chip nudibranch, Aphelodoris sp. 1, is an undescribed species of dorid nudibranch as designated by Gosliner, 1987. It is a marine gastropod mollusc in the family Dorididae. As of November 2009, it was undescribed by academics.

<i>Rostanga elandsia</i> species of mollusc

Rostanga elandsia, is a species of dorid nudibranch. It is a marine gastropod mollusc in the family Discodorididae.

<i>Goniobranchus heatherae</i> species of mollusc

Goniobranchus heatherae, the red-spotted nudibranch, is a species of colourful sea slug, a dorid nudibranch. It is a marine gastropod mollusc in the family Chromodorididae.

Cape dorid species of mollusc

The Cape dorid is a species of sea slug, a dorid nudibranch. It is a marine gastropod mollusc in the family Chromodorididae.

Inkspot nudibranch species of myriapod

The inkspot nudibranch, Ceratosoma ingozi, is a species of colourful sea slug, a dorid nudibranch. It is a marine gastropod mollusc in the family Chromodorididae.

Mandelas nudibranch species of Gastropoda

Mandela's nudibranch, Mandelia mirocornata, is a species of sea slug, a dorid nudibranch. It is a marine gastropod mollusc, the only member of the genus Mandelia and the family Mandeliidae. The genus and family name honor Nelson Mandela, the former President of South Africa.

Saddled nudibranch species of Gastropoda

The saddled nudibranch, scientific name Cadlina sp.1 as designated by Gosliner, 1987, is a species of colourful sea slug, a dorid nudibranch. It is a marine gastropod mollusc in the family Cadlinidae.

Brown-dotted nudibranch species of Gastropoda

The brown-dotted nudibranch, Cadlina sp.2, as designated by Gosliner, 1987, is a species of colourful sea slug, a dorid nudibranch. It is a marine gastropod mollusc in the family Cadlinidae.

Blue-speckled nudibranch species of mollusc

The blue-speckled nudibranch is a species of sea slug, a dorid nudibranch. It is a marine gastropod mollusc in the family Dendrodorididae.

White-spotted nudibranch species of mollusc

The white-spotted nudibranch is a species of sea slug, a dorid nudibranch. It is a marine gastropod mollusc in the family Dendrodorididae.

Giraffe spot nudibranch species of mollusc

The giraffe spot nudibranch, Ancula sp., as designated by Gosliner, 1987, is a species of colourful sea slug, specifically a dorid nudibranch, a marine gastropod mollusc in the family Goniodorididae. As of November 2009, it remained undescribed by science.

Tasselled nudibranch species of mollusc

The tasselled nudibranch, scientific name Kaloplocamus ramosus, is a species of sea slug, a dorid nudibranch, and a marine gastropod mollusc in the family Polyceridae.

Acanthodoris planca is a species of dorid nudibranch. It is a marine gastropod mollusc in the family Onchidorididae.

Black nudibranch species of mollusc

The black nudibranch is a species of colorful sea slug, a dorid nudibranch, a shell-less marine gastropod mollusk in the family Polyceridae. This species is endemic to South Africa.

Aldisa albomarginata is a species of sea slug, a dorid nudibranch, a marine gastropod mollusk in the family Cadlinidae.

Aldisa tara is a species of sea slug, a dorid nudibranch, a marine gastropod mollusk in the family Cadlinidae.

Aldisa benguelae is a species of sea slug, a dorid nudibranch, a marine gastropod mollusk in the family Cadlinidae.

Rostanga phepha, is a species of sea slug, a dorid nudibranch, a marine gastropod mollusc in the family Discodorididae.

References

  1. Gosliner, T.M. 1987. Nudibranchs of Southern Africa ISBN   0-930118-13-8
  2. Zsilavecz, G. 2007. Nudibranchs of the Cape Peninsula and False Bay. ISBN   0-620-38054-3