Lepas anserifera
Encyclopedia
Lepas anserifera is a species
of goose barnacle or stalked barnacle
in the family
Lepadidae
. It lives attached to floating timber, ships' hulls and various sorts of flotsam.
enclosed in six white plates supported by a tough, flexible, orange stalk or peduncle
. The capitulum is about 4 centimetres (1.6 in) long and the stalk a similar length. The limy plates are thick and sculptured and are in close contact with each other. The largest plates, the pair of scuta at the stalk end, are quadrangular with longitudinal furrows and a smooth umbonal area. The pair of terga at the free end are trapezoid and more furrowed than the scutum and the carina in between are wide and forked. The tergal flaps are yellow, giving a coloured rim to the plates in the living animal. The body concealed by these plates consists of a head and thorax with a vestigial abdomen. The head bears the mouthparts consisting of a labrum with fine teeth on the inner margin, a blunt palpus, mandibles and maxillae. The thorax bears three pairs of maxillipeds and cirri with five or six pairs of long feeding appendages. The caudal appendages are curved and pointed which helps distinguish Lepas anserifera from other species.
being found chiefly in temperate and tropical seas. It is normally found growing in clusters and anchored by its peduncle to driftwood and other floating objects, including whale
s. It is sometimes found washed up on beaches still attached to this flotsam.
. The life cycle is complex and involves a nauplius and a cyprid larval stage during which the animal is mobile and forms part of the plankton. The larva then settles on a suitable surface before undergoing metamorphosis
and becoming a sessile
, pedunculate juvenile.
Lepas anserifera is a filter feeder
. The feather-like cirri are repeatedly fanned out and then retracted inside the plates to create a current and draw in zooplankton
and detritus
for consumption.
of birds was not properly understood and, in an attempt to explain the fact that the goose, Branta leucopsis, was never known to breed, it was believed that the birds' young hatched from the goose barnacles found in floating "nests" on the beach. The specific name derives from this with "anser" being the Latin
for "goose" while "fera" translates as "bearing".
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 goose barnacle or stalked barnacle
Barnacle
A barnacle is a type of arthropod belonging to infraclass 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 suspension feeders, and have...
in the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Lepadidae
Lepadidae
Lepadidae is a family of goose barnacles, erected by Charles Darwin in 1852. It contains the three genera Lepas, Conchoderma and Dosima....
. It lives attached to floating timber, ships' hulls and various sorts of flotsam.
Description
Lepas anserifera has a shell or capitulumCapitulum
The term Capitulum can refer to several things:*In botany, a type of flower head where the bracts are located under the basis, such as a daisy's*Also in botany, the top of a Sphagnum moss plant with compact clusters of young branches....
enclosed in six white plates supported by a tough, flexible, orange stalk or peduncle
Peduncle
The term peduncle has several meanings:*Peduncle , a stalk supporting an inflorescence, which is the part of the shoot of seed plants where flowers are formed...
. The capitulum is about 4 centimetres (1.6 in) long and the stalk a similar length. The limy plates are thick and sculptured and are in close contact with each other. The largest plates, the pair of scuta at the stalk end, are quadrangular with longitudinal furrows and a smooth umbonal area. The pair of terga at the free end are trapezoid and more furrowed than the scutum and the carina in between are wide and forked. The tergal flaps are yellow, giving a coloured rim to the plates in the living animal. The body concealed by these plates consists of a head and thorax with a vestigial abdomen. The head bears the mouthparts consisting of a labrum with fine teeth on the inner margin, a blunt palpus, mandibles and maxillae. The thorax bears three pairs of maxillipeds and cirri with five or six pairs of long feeding appendages. The caudal appendages are curved and pointed which helps distinguish Lepas anserifera from other species.
Distribution
Lepas anserifera has a cosmopolitan distributionCosmopolitan distribution
In biogeography, a taxon is said to have a cosmopolitan distribution if its range extends across all or most of the world in appropriate habitats. For instance, the killer whale has a cosmopolitan distribution, extending over most of the world's oceans. Other examples include humans, the lichen...
being found chiefly in temperate and tropical seas. It is normally found growing in clusters and anchored by its peduncle to driftwood and other floating objects, including whale
Whale
Whale is the common name for various marine mammals of the order Cetacea. The term whale sometimes refers to all cetaceans, but more often it excludes dolphins and porpoises, which belong to suborder Odontoceti . This suborder also includes the sperm whale, killer whale, pilot whale, and beluga...
s. It is sometimes found washed up on beaches still attached to this flotsam.
Biology
Lepas anserifera is a hermaphroditeHermaphrodite
In biology, a hermaphrodite is an organism that has reproductive organs normally associated with both male and female sexes.Many taxonomic groups of animals do not have separate sexes. In these groups, hermaphroditism is a normal condition, enabling a form of sexual reproduction in which both...
. The life cycle is complex and involves a nauplius and a cyprid larval stage during which the animal is mobile and forms part of the plankton. The larva then settles on a suitable surface before undergoing metamorphosis
Metamorphosis
Metamorphosis is a biological process by which an animal physically develops after birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation...
and becoming a sessile
Sessility (zoology)
In zoology, sessility is a characteristic of animals which are not able to move about. They are usually permanently attached to a solid substrate of some kind, such as a part of a plant or dead tree trunk, a rock, or the hull of a ship in the case of barnacles. Corals lay down their own...
, pedunculate juvenile.
Lepas anserifera is a filter feeder
Filter feeder
Filter feeders are animals that feed by straining suspended matter and food particles from water, typically by passing the water over a specialized filtering structure. Some animals that use this method of feeding are clams, krill, sponges, baleen whales, and many fish and some sharks. Some birds,...
. The feather-like cirri are repeatedly fanned out and then retracted inside the plates to create a current and draw in zooplankton
Zooplankton
Zooplankton are heterotrophic plankton. Plankton are organisms drifting in oceans, seas, and bodies of fresh water. The word "zooplankton" is derived from the Greek zoon , meaning "animal", and , meaning "wanderer" or "drifter"...
and detritus
Detritus
Detritus is a biological term used to describe dead or waste organic material.Detritus may also refer to:* Detritus , a geological term used to describe the particles of rock produced by weathering...
for consumption.
Mythology
Lepas anserifera is called a goose barnacle because its shape resembles that of a goose. Before about 1100 AD, the migrationBird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
of birds was not properly understood and, in an attempt to explain the fact that the goose, Branta leucopsis, was never known to breed, it was believed that the birds' young hatched from the goose barnacles found in floating "nests" on the beach. The specific name derives from this with "anser" being the Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
for "goose" while "fera" translates as "bearing".