''Dosima fascicularis'', the buoy barnacle, is "the most specialised

pleuston Neuston, also known as pleuston, are organisms that live at the surface of the ocean or an estuary, or at the surface of a lake, river or pond. Neuston can live on top of the water surface or may be attached to the underside of the water surface. ...

ic goose barnacle"

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 ...

. It hangs downwards from the water surface, held up by a float of its own construction, and is carried along by

ocean current An ocean current is a continuous, directed movement of sea water generated by a number of forces acting upon the water, including wind, the Coriolis effect, breaking waves, cabbeling, and temperature and salinity differences. Depth contours, s ...

Flotation

As an adult, ''D. fascicularis'' lives attached to a float made either of natural flotsam or of a cement it secretes itself, which has a texture like that of

expanded polystyrene foam Polystyrene (PS) is a synthetic polymer made from monomers of the Aromatic hydrocarbon, aromatic hydrocarbon styrene. Polystyrene can be solid or foamed. General-purpose polystyrene is clear, hard, and brittle. It is an inexpensive resin pe ...

. It is the only barnacle to produce its own gas-filled float. The cyprid

larvae A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. The ...

are

plankton Plankton are the diverse collection of organisms found in Hydrosphere, water (or atmosphere, air) that are unable to propel themselves against a Ocean current, current (or wind). The individual organisms constituting plankton are called plankt ...

ic, and must attach to a float for

metamorphosis Metamorphosis is a biological process by which an animal physically develops including birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation. Some inse ...

into the adult form, but the adults are eventually capable of using their own float, sometimes forming aggregations of many individuals attached to a single float. Among the floats used by adult buoy barnacles are pellets of

tar Tar is a dark brown or black viscous liquid of hydrocarbons and free carbon, obtained from a wide variety of organic materials through destructive distillation. Tar can be produced from coal, wood, petroleum, or peat. "a dark brown or black bit ...

seaweed Seaweed, or macroalgae, refers to thousands of species of macroscopic, multicellular, marine algae. The term includes some types of '' Rhodophyta'' (red), ''Phaeophyta'' (brown) and ''Chlorophyta'' (green) macroalgae. Seaweed species such as ...

plastic Plastics are a wide range of synthetic or semi-synthetic materials that use polymers as a main ingredient. Their plasticity makes it possible for plastics to be moulded, extruded or pressed into solid objects of various shapes. This adaptab ...

debris,

driftwood __NOTOC__ Driftwood is wood that has been washed onto a shore or beach of a sea, lake, or river by the action of winds, tides or waves. In some waterfront areas, driftwood is a major nuisance. However, the driftwood provides shelter and fo ...

feather Feathers are epidermal growths that form a distinctive outer covering, or plumage, on both avian (bird) and some non-avian dinosaurs and other archosaurs. They are the most complex integumentary structures found in vertebrates and a premier ...

cranberries Cranberries are a group of evergreen dwarf shrubs or trailing vines in the subgenus ''Oxycoccus'' of the genus ''Vaccinium''. In Britain, cranberry may refer to the native species ''Vaccinium oxycoccos'', while in North America, cranberry m ...

, cuttlefish bone, the "by-the-wind-sailor" '' Velella velella'',

seagrass Seagrasses are the only flowering plants which grow in marine environments. There are about 60 species of fully marine seagrasses which belong to four families (Posidoniaceae, Zosteraceae, Hydrocharitaceae and Cymodoceaceae), all in the orde ...

leaves A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...

, Styrofoam,

seed A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiospe ...

s, and even

apple An apple is an edible fruit produced by an apple tree (''Malus domestica''). Apple fruit tree, trees are agriculture, cultivated worldwide and are the most widely grown species in the genus ''Malus''. The tree originated in Central Asia, wh ...

s; they have even been known to colonise the backs of

turtle Turtles are an order of reptiles known as Testudines, characterized by a special shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira (side necked turtles) and Cryptodira (hidden necked tu ...

s and the

sea snake Sea snakes, or coral reef snakes, are elapid snakes that inhabit marine environments for most or all of their lives. They belong to two subfamilies, Hydrophiinae and Laticaudinae. Hydrophiinae also includes Australasian terrestrial snakes, wher ...

Pelamis platurus The yellow-bellied sea snake (''Hydrophis platurus'') is a venomous species of snake from the subfamily Hydrophiinae (the sea snakes) found in tropical oceanic waters around the world except for the Atlantic Ocean. For many years, it was place ...

''. It is a fugitive species, which can be out-competed by other barnacle species, and relies on being able to colonise surfaces and reproduce quickly; after settling on a float, ''D. fascicularis'' can reproduce within 45 days. ''D. fascicularis'' appears to be increasing in abundance as a result of anthropogenic

marine debris Marine debris, also known as marine litter, is human-created waste that has deliberately or accidentally been released in a sea or ocean. Floating oceanic debris tends to accumulate at the center of gyres and on coastlines, frequently washing ...

accumulating in the sea; this source of floats was of "minor importance" in 1974.

Related species

Although formerly placed in the genus ''

Lepas ''Lepas'' is a genus of goose barnacles in the family Lepadidae. Species Species in the genus include: * '' Lepas anatifera'' Linnaeus, 1758 * ''Lepas anserifera'' Linnaeus, 1767 * '' Lepas australis'' Darwin, 1851 * ''Lepas hilli ''Lepas'' ...

'', the buoy barnacle is now generally placed in the genus, ''Dosima''. ''Dosima'' is distinguished from ''Lepas'' by the form of the ''carina'', and by the exceptional thinness and brittleness of its

exoskeleton An exoskeleton (from Greek ''éxō'' "outer" and ''skeletós'' "skeleton") is an external skeleton that supports and protects an animal's body, in contrast to an internal skeleton (endoskeleton) in for example, a human. In usage, some of the ...

Distribution

''D. fascicularis'' has a

cosmopolitan distribution In biogeography, cosmopolitan distribution is the term for the range of a taxon that extends across all or most of the world in appropriate habitats. Such a taxon, usually a species, is said to exhibit cosmopolitanism or cosmopolitism. The ext ...

, with a preference for temperate seas, having been found at latitudes from 71° North off

Siberia Siberia ( ; rus, Сибирь, r=Sibir', p=sʲɪˈbʲirʲ, a=Ru-Сибирь.ogg) is an extensive geographical region, constituting all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has been a part of ...

to 57° South near

Cape Horn Cape Horn ( es, Cabo de Hornos, ) is the southernmost headland of the Tierra del Fuego archipelago of southern Chile, and is located on the small Hornos Island. Although not the most southerly point of South America (which are the Diego Ramírez ...

. Groups have been observed journeying from

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

to the

Hawaiian Islands The Hawaiian Islands ( haw, Nā Mokupuni o Hawai‘i) are an archipelago of eight major islands, several atolls, and numerous smaller islets in the North Pacific Ocean, extending some from the island of Hawaii in the south to northernmost Kur ...

in the

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...

, and sometimes wash up on westerly and southerly beaches in the

British Isles The British Isles are a group of islands in the North Atlantic Ocean off the north-western coast of continental Europe, consisting of the islands of Great Britain, Ireland, the Isle of Man, the Inner and Outer Hebrides, the Northern Isles, ...

, as well as westerly beaches further south in Europe. It is not normally found in 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 ...

, but may have begun to colonise there from the

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...

References

{{Taxonbar, from=Q6569712 Barnacles Taxa named by John Edward Gray