Cadlina laevis
Encyclopedia
Cadlina laevis, common name
the white Atlantic cadlina, is a species
of sea slug
, a dorid nudibranch
, a shell-less marine
gastropod mollusk in the family Cadlinidae
.
to depths of 800 m, ranging from the Arctic to the North Atlantic (Canadian Arctic Archipelago, Spitsbergen
, Iceland
, Greenland
). Along the North American coast its range reaches as far south as Massachusetts
. It also occurs along the European coast from Norway
to northern Spain
. The reporting of a Cadlina with yellow markings near the Portuguese west coast could be an unnamed species of Cadlina.
The short, cephalic tentacles are comblike, and the short, tripinnate gills at the back are crytobranchiate, i.e. they can retract at the same time in a common branchial pit.
The observed length of these sea slugs varies between 25 mm and 32 mm.
The maximum recorded length is 17 mm.
This nudibranch preys on encrusting slime sponges, such as Halisarca dujardini or, in deeper waters, the sponge Dysidea fragilis. They are reported to breed at the end of winter. The penis of the male is encrusted with tiny chitin
ous hooks. They reproduce by direct development. When the eggs hatch after ca. fifty days, they give small slugs, forgoing the planktonic larval stage. The veliger
phase occurs within the eggs.
Common name
A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...
the white Atlantic cadlina, 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 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 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 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 Cadlinidae
Cadlinidae
Cadlinidae is a family of sea slugs, dorid nudibranchs, marine gastropod mollusks in the superfamily Doridoidea. This family is within the clade Euctenidiacea....
.
Distribution
The white Atlantic cadlina is found, dispersed in widely separated populations, on rocky bottoms from the low tide zoneIntertidal 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...
to depths of 800 m, ranging from the Arctic to the North Atlantic (Canadian Arctic Archipelago, Spitsbergen
Spitsbergen
Spitsbergen is the largest and only permanently populated island of the Svalbard archipelago in Norway. Constituting the western-most bulk of the archipelago, it borders the Arctic Ocean, the Norwegian Sea and the Greenland Sea...
, Iceland
Iceland
Iceland , described as the Republic of Iceland, is a Nordic and European island country in the North Atlantic Ocean, on the Mid-Atlantic Ridge. Iceland also refers to the main island of the country, which contains almost all the population and almost all the land area. The country has a population...
, Greenland
Greenland
Greenland is an autonomous country within the Kingdom of Denmark, located between the Arctic and Atlantic Oceans, east of the Canadian Arctic Archipelago. Though physiographically a part of the continent of North America, Greenland has been politically and culturally associated with Europe for...
). Along the North American coast its range reaches as far south as Massachusetts
Massachusetts
The Commonwealth of Massachusetts is a state in the New England region of the northeastern United States of America. It is bordered by Rhode Island and Connecticut to the south, New York to the west, and Vermont and New Hampshire to the north; at its east lies the Atlantic Ocean. As of the 2010...
. It also occurs along the European coast from Norway
Norway
Norway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...
to northern Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...
. The reporting of a Cadlina with yellow markings near the Portuguese west coast could be an unnamed species of Cadlina.
Description
They have a flattened, white, semitransparant, oval mantle. There appear to be two color varieties: one showing bright yellow spots near the thin, yellow margin on the back, the other is milky white and lacks spots. There is also an intermediate form with milky yellow spots. These forms do not seem to occur together: the yellow-spotted form lives in deeper water, whereas the other form lives intertidally.The short, cephalic tentacles are comblike, and the short, tripinnate gills at the back are crytobranchiate, i.e. they can retract at the same time in a common branchial pit.
The observed length of these sea slugs varies between 25 mm and 32 mm.
The maximum recorded length is 17 mm.
Ecology
Minimum recorded depth is 0 m. Maximum recorded depth is 250 m.This nudibranch preys on encrusting slime sponges, such as Halisarca dujardini or, in deeper waters, the sponge Dysidea fragilis. They are reported to breed at the end of winter. The penis of the male is encrusted with tiny chitin
Chitin
Chitin n is a long-chain polymer of a N-acetylglucosamine, a derivative of glucose, and is found in many places throughout the natural world...
ous hooks. They reproduce by direct development. When the eggs hatch after ca. fifty days, they give small slugs, forgoing the planktonic larval stage. The veliger
Veliger
A veliger is the planktonic larva of many kinds of marine and freshwater gastropod molluscs, as well as most bivalve mollusks.- Description :...
phase occurs within the eggs.
Further reading
- Thompson T. E. (1967). "Direct development in a Nudibranch, Cadlina laevis, with a discussion of developmental processes in Opisthobranchia". Journal of the Marine Biological Association of the United KingdomJournal of the Marine Biological Association of the United KingdomThe Journal of the Marine Biological Association of the United Kingdom is a scientific journal published by Cambridge University Press on behalf of the Marine Biological Association of the United Kingdom....
47(1): 1-22. doi:10.1017/S0025315400033518