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Barnacle
A barnacle is a type of arthropod constituting the subclass Cirripedia in the subphylum Crustacea, and is hence related to crabs and lobsters. Barnacles are exclusively marine, and tend to live in shallow and tidal waters, typically in erosive settings. They are sessile (nonmobile) and most are suspension feeders, but those in infraclass Rhizocephala are highly specialized parasites on crustaceans. They have four nektonic (active swimming) larval stages. Around 1,000 barnacle species are currently known. The name is Latin, meaning "curl-footed". The study of barnacles is called cirripedology. Description Barnacles are encrusters, attaching themselves temporarily to a hard substrate or a symbiont such as a whale (whale barnacles), a sea snake ('' Platylepas ophiophila''), or another crustacean, like a crab or a lobster ( Rhizocephala). The most common among them, "acorn barnacles" ( Sessilia), are sessile where they grow their shells directly onto the substrate. Peduncul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whale Barnacle
Whale barnacles are species of acorn barnacle that belong to the family Coronulidae. They typically attach to baleen whales, and sometimes settle on toothed whales. The whale barnacles diverged from the turtle barnacles about three million years ago. Whale barnacles passively filter food, using tentacle-like cirri, as the host swims through the water. The arrangement is generally considered commensal as it is done at no cost or benefit to the host. However, some whales may make use of the barnacles as protective armor or for inflicting more damage while fighting, which would make the relationship mutualistic where both parties benefit; alternatively, some species may just increase the drag that the host experiences while swimming, making the barnacles parasites. After hatching, whale barnacles go through six molting stages before searching for a host, being prompted to settle by a chemical cue from the host skin. The barnacle creates a crown-shaped shell, and in most instan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goose Barnacle
Goose barnacles, also called stalked barnacles or gooseneck barnacles, are filter-feeding crustaceans that live attached to hard surfaces of rocks and flotsam in the ocean intertidal zone. Goose barnacles formerly made up the taxonomic order Pedunculata, but research has resulted in the classification of stalked barnacles within multiple orders of the infraclass Thoracica. Biology Some species of goose barnacles such as '' Lepas anatifera'' are pelagic and are most frequently found on tidewrack on oceanic coasts. Unlike most other types of barnacles, intertidal goose barnacles (e.g. '' Pollicipes pollicipes'' and ''Pollicipes polymerus'') depend on water motion rather than the movement of their cirri for feeding, and are therefore found only on exposed or moderately exposed coasts. Spontaneous generation In the days before it was realised that birds migrate, it was thought that barnacle geese, ''Branta leucopsis'', developed from this crustacean through spontaneous ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chthamalus Stellatus
''Chthamalus stellatus'', common name Poli's stellate barnacle, is a species of acorn barnacle common on rocky shores in South West England, Ireland, and Southern Europe. It is named after Giuseppe Saverio Poli. Description ''C. stellatus'' is a sessile barnacle that attaches to rocks and other firm materials in the intertidal zone using its membranous base. It is basically cone-shaped but can assume a more tubular shape in a crowded colony. Like other sessile barnacles, as an adult ''C. stellatus'' is a suspension feeder that stays in its fixed shell and uses its feathery, rhythmically beating appendages – actually modified legs – to draw plankton and detritus into its shell for consumption. The chalky white shell of ''C. stellatus'' has a kite-shaped opercular opening when it is a juvenile and an oval operculum opening when it is an adult. The shell is made up of six solid wall plates of approximately equal size. Its relatively narrow rostral plates remain separate fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Platylepas Ophiophila
''Platylepas ophiophila'', commonly known as the sea snake barnacle, is a species of barnacle in the family Platylepadidae. It is native to the Indo-Pacific Ocean where it lives as a symbiont of a sea snake. Ecology ''Platylepas ophiophila'' is found living in association with several species of sea snake as an ectosymbiont. The barnacle adheres to the snake's skin, and has ribs that penetrate the snake's skin to make the attachment more secure. Nevertheless, the barnacle usually becomes detached when the snake sheds its skin. Barnacles breed by internal fertilisation, so individuals of this species have to be located adjacent to another individual in order to reproduce. Despite the fact that sea snakes are mobile and generally solitary, about half the sea snakes support barnacles. The barnacle may have adopted this lifestyle as a result of intense competition for space on coral reefs, rocks and other hard substrates; the advantages for the barnacle are freedom from predators ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhizocephala
Rhizocephala are derived barnacles that parasitise mostly decapod crustaceans, but can also infest Peracarida, mantis shrimps and thoracican barnacles, and are found from the deep ocean to freshwater. Together with their sister groups Thoracica and Acrothoracica, they make up the subclass Cirripedia. Their body plan is uniquely reduced in an extreme adaptation to their parasitic lifestyle, and makes their relationship to other barnacles unrecognisable in the adult form. The name Rhizocephala derives from the Ancient Greek roots (, "root") and (, "head"), describing the adult female, which mostly consists of a network of thread-like extensions penetrating the body of the host. Description and lifecycle As adults they lack appendages, segmentation, and all internal organs except gonads, a few muscles, and the remains of the nervous system. Females also have a cuticle, which is never shed. Other than the minute larval stages, there is nothing identifying them as crustacean ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sessilia Sessilia is an unranked clade of barnacles, comprising the barnacles without stalks, or acorn barnacles. They form a monophyletic group and are probably derived from stalked or goose barnacles. Sessilia is divided into two orders. The Verrucomorpha contain two families, Verrucidae and Neoverrucidae, and the remaining 14 families are in the order Balanomorpha The Balanomorpha are an order of barnacles, containing familiar acorn barnacles of the seashore. The order contains these families: * Austrobalanidae Newman & Ross, 1976 * Balanidae Leach, 1817 (acorn barnacles) * Bathylasmatidae Newman & Ross .... References External links * Barnacles Crustacean orders {{maxillopoda-stub da:Rur de:Seepocken pl:Pąkle ... [...More Info...] |
