''Lepas anatifera'', commonly known as the pelagic gooseneck barnacle or smooth gooseneck barnacle, 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 ...

of barnacle 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 ...

Lepadidae Lepadidae is a family of goose barnacles, erected by Charles Darwin in 1852. There are about five genera and more than 20 described species in Lepadidae. Genera These genera belong to the family Lepadidae: * ''Conchoderma'' von Olfers, 1814 (wha ...

. These barnacles are found, often in large numbers, attached by their flexible stalks to floating timber, the hulls of ships, piers, pilings, seaweed, and various sorts of

flotsam In maritime law, flotsam'','' jetsam'','' lagan'','' and derelict are specific kinds of shipwreck. The words have specific nautical meanings, with legal consequences in the law of admiralty and marine salvage. A shipwreck is defined as the rema ...

Description

The body or capitulum of ''Lepas anatifera'' is supported by a long, flexible stalk or peduncle. There are five smooth, translucent plates, edged with scarlet and separated by narrow gaps. The plates have growth lines parallel with their margins and a few faint radial sculpture lines. Inside the capitulum, the barnacle has a head, a thorax, and a vestigial abdomen. A number of brown, filamentous cirri or feeding tentacles project from between the plates. The peduncle is tough and a purplish-brown colour. The capitulum may grow to a length of and the peduncle varies between and .''Lepas anatifera''
Marine Species Identification Portal. Retrieved 2011-12-02.

Distribution

''Lepas anatifera'' has a cosmopolitan distribution and is found in tropical and subtropical seas worldwide. Because it frequently is attached to objects carried into colder seas by currents, such as the

North Atlantic Drift The North Atlantic Current (NAC), also known as North Atlantic Drift and North Atlantic Sea Movement, is a powerful warm western boundary current within the Atlantic Ocean that extends the Gulf Stream northeastward. The NAC originates from where ...

, it often is found well away from its place of origin and in waters too cold for it to reproduce. In this way, it has been documented in

Norway Norway, officially the Kingdom of Norway, is a Nordic country in Northern Europe, the mainland territory of which comprises the western and northernmost portion of the Scandinavian Peninsula. The remote Arctic island of Jan Mayen and the ...

, the Shetland Islands, the

Faeroe Islands The Faroe Islands ( ), or simply the Faroes ( fo, Føroyar ; da, Færøerne ), are a North Atlantic island group and an autonomous territory of the Kingdom of Denmark. They are located north-northwest of Scotland, and about halfway betwee ...

Iceland Iceland ( is, Ísland; ) is a Nordic island country in the North Atlantic Ocean and in the Arctic Ocean. Iceland is the most sparsely populated country in Europe. Iceland's capital and largest city is Reykjavík, which (along with its s ...

, and Spitsbergen.

Biology

''Lepas anatifera'' is a hermaphrodite and starts to breed when it is about 2.5 centimetres (1 in) long. Fertilisation is internal and the

eggs Humans and human ancestors have scavenged and eaten animal eggs for millions of years. Humans in Southeast Asia had domesticated chickens and harvested their eggs for food by 1,500 BCE. The most widely consumed eggs are those of fowl, especial ...

are brooded inside the mantle for a week before emerging as free-swimming nauplius larvae. After further development, drifting as part of the

plankton Plankton are the diverse collection of organisms found in water (or air) that are unable to propel themselves against a current (or wind). The individual organisms constituting plankton are called plankters. In the ocean, they provide a crucia ...

, these settle onto floating objects.''Lepas anatifera'' Linnaeus, 1758
WallaWalla. Retrieved 2011-12-02. ''Lepas anatifera'' has long been known to grow on

sea turtle Sea turtles (superfamily Chelonioidea), sometimes called marine turtles, are reptiles of the order Testudines and of the suborder Cryptodira. The seven existing species of sea turtles are the flatback, green, hawksbill, leatherback, loggerhe ...

s, but in 2008, some small specimens were found attached to an

American crocodile The American crocodile (''Crocodylus acutus'') is a species of crocodilian found in the Neotropics. It is the most widespread of the four extant species of crocodiles from the Americas, with populations present from South Florida and the coasts ...

(''Crocodylus acutus'') on the Pacific coast of

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

. That crocodile species mostly inhabits

mangrove A mangrove is a shrub or tree that grows in coastal saline or brackish water. The term is also used for tropical coastal vegetation consisting of such species. Mangroves are taxonomically diverse, as a result of convergent evolution in severa ...

swamps and river estuaries, but it is salt tolerant, and sometimes is found in marine environments. In this instance, the size of the goose-neck barnacles indicated that the crocodile must have been in the sea for at least a week. That is the first time that ''Lepas anatifera'' has been recorded as an

epibiont An epibiont (from the Ancient Greek meaning "living on top of") is an organism that lives on the surface of another living organism, called the basibiont ("living underneath"). The interaction between the two organisms is called epibiosis. An ep ...

of a

crocodilia Crocodilia (or Crocodylia, both ) is an order of mostly large, predatory, semiaquatic reptiles, known as crocodilians. They first appeared 95 million years ago in the Late Cretaceous period ( Cenomanian stage) and are the closest livi ...

Origin of the name

In thirteenth-century England the word "barnacle" was used for a species of waterfowl, the

barnacle goose The barnacle goose (''Branta leucopsis'') is a species of goose that belongs to the genus '' Branta'' of black geese, which contains species with largely black plumage, distinguishing them from the grey ''Anser'' species. Despite its superficial ...

(''Branta leucopsis''). This bird breeds in the Arctic, but winters in the British Isles so its nests and eggs were never seen by the British. At the time, it was thought that the gooseneck barnacles that wash up occasionally on the shore had spontaneously generated from the rotting wood to which they were attached, and therefore, that the geese might be generated similarly. Credence to the idea was provided by the tuft of brown cirri that protruded from the capitulum of the crustaceans that resembled the down of an unhatched gosling. Popular belief linked the two species and a writer in 1678 wrote "multitudes of little Shells; having within them little Birds perfectly shap'd, supposed to be Barnacles y which he meant barnacle geese"Barnacle
American Heritage Dictionary. Retrieved 2011-12-04.

References

{{Taxonbar, from=Q2716301 Barnacles Cosmopolitan arthropods Crustaceans of the Atlantic Ocean Crustaceans of the Indian Ocean Crustaceans of the Pacific Ocean Crustaceans described in 1758 Taxa named by Carl Linnaeus