Pisidia longicornis
Encyclopedia
Pisidia longicornis, the long-clawed porcelain crab, is a species
of porcelain crab
that lives in the north-eastern Atlantic Ocean
. It varies from reddish to white, and grows to a carapace
width of 1 cm (0.393700787401575 in). It was first named by Carl Linnaeus in 1767, although the etymology remains unclear.
length of 1 centimetre (0.393700787401575 in). Its colouration is variable, with most individuals being reddish or orange, but some having patches of pearl
y white, or even being entirely white. One cheliped (claw-bearing appendage
) is usually larger than the other, although this difference is less pronounced in females than in males. The fifth pair of legs is reduced in size and may be difficult to see.
from Norway
to Angola
, and throughout the Mediterranean Sea
. It is found from the lower shore down to depths of 70 metres (229.7 ft) in the north Atlantic, but at depths of 30 metre in some locations around the Mediterranean Sea. It lives under boulders and among bryozoa
n turfs, and may occasionally be found in fish market
s among mussel
s and oyster
s.
It feeds by filtering
suspended material from the sea water. Individuals from the intertidal zone
tend to be larger than those from deeper water, which may be related to the greater churning of the sediment by the tide
.
, and from February to September in the Mediterranean Sea. Young Pisidia longicornis go through two zoeal (larval) stages before reaching the megalopa (post-larval) stage. The zoea larvae bear "exceptionally long" spines on the carapace
, one directed forwards, and two directed backwards. The second zoeal stage may reach a length of 10 millimetre (0.393700787401575 in), while the megalopa has a carapace
width of 1.5 mm (0.0590551181102362 in).
of his Systema Naturae
. The specific epithet is difficult to explain, it being Latin
for "long-horned", from and ; it may refer to the long chelipeds (claw-bearing appendages). The species was moved from the genus Porcellana
by William Elford Leach
when he established the genus Pisidia
in 1820.
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 porcelain crab
Porcelain crab
Porcelain crabs are decapod crustaceans in the widespread family Porcellanidae, which superficially resemble true crabs. They are typically less than wide, and have flattened bodies as an adaptation for living in rock crevices...
that lives in the north-eastern Atlantic Ocean
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
. It varies from reddish to white, and grows to a carapace
Carapace
A carapace is a dorsal section of the exoskeleton or shell in a number of animal groups, including arthropods such as crustaceans and arachnids, as well as vertebrates such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron.-Crustaceans:In crustaceans, the...
width of 1 cm (0.393700787401575 in). It was first named by Carl Linnaeus in 1767, although the etymology remains unclear.
Description
Adult Pisidia longicornis typically have a carapaceCarapace
A carapace is a dorsal section of the exoskeleton or shell in a number of animal groups, including arthropods such as crustaceans and arachnids, as well as vertebrates such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron.-Crustaceans:In crustaceans, the...
length of 1 centimetre (0.393700787401575 in). Its colouration is variable, with most individuals being reddish or orange, but some having patches of pearl
Pearl
A pearl is a hard object produced within the soft tissue of a living shelled mollusk. Just like the shell of a mollusk, a pearl is made up of calcium carbonate in minute crystalline form, which has been deposited in concentric layers. The ideal pearl is perfectly round and smooth, but many other...
y white, or even being entirely white. One cheliped (claw-bearing appendage
Appendage
In invertebrate biology, an appendage is an external body part, or natural prolongation, that protrudes from an organism's body . It is a general term that covers any of the homologous body parts that may extend from a body segment...
) is usually larger than the other, although this difference is less pronounced in females than in males. The fifth pair of legs is reduced in size and may be difficult to see.
Distribution and ecology
Pisidia longicornis is found in the north-eastern Atlantic OceanAtlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
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 Angola
Angola
Angola, officially the Republic of Angola , is a country in south-central Africa bordered by Namibia on the south, the Democratic Republic of the Congo on the north, and Zambia on the east; its west coast is on the Atlantic Ocean with Luanda as its capital city...
, and throughout the Mediterranean Sea
Mediterranean Sea
The Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...
. It is found from the lower shore down to depths of 70 metres (229.7 ft) in the north Atlantic, but at depths of 30 metre in some locations around the Mediterranean Sea. It lives under boulders and among bryozoa
Bryozoa
The Bryozoa, also known as Ectoprocta or commonly as moss animals, are a phylum of aquatic invertebrate animals. Typically about long, they are filter feeders that sieve food particles out of the water using a retractable lophophore, a "crown" of tentacles lined with cilia...
n turfs, and may occasionally be found in fish market
Fish market
A fish market is a marketplace used for marketing fish products. It can be dedicated to wholesale trade between fishermen and fish merchants, or to the sale of seafood to individual consumers, or to both...
s among mussel
Mussel
The common name mussel is used for members of several families of clams or bivalvia mollusca, from saltwater and freshwater habitats. These groups have in common a shell whose outline is elongated and asymmetrical compared with other edible clams, which are often more or less rounded or oval.The...
s and oyster
Oyster
The word oyster is used as a common name for a number of distinct groups of bivalve molluscs which live in marine or brackish habitats. The valves are highly calcified....
s.
It feeds by filtering
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,...
suspended material from the sea water. Individuals from the intertidal zone
Intertidal 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...
tend to be larger than those from deeper water, which may be related to the greater churning of the sediment by the tide
Tide
Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the moon and the sun and the rotation of the Earth....
.
Life cycle
Females bear eggs from March to August around the British IslesBritish Isles
The British Isles are a group of islands off the northwest coast of continental Europe that include the islands of Great Britain and Ireland and over six thousand smaller isles. There are two sovereign states located on the islands: the United Kingdom of Great Britain and Northern Ireland and...
, and from February to September in the Mediterranean Sea. Young Pisidia longicornis go through two zoeal (larval) stages before reaching the megalopa (post-larval) stage. The zoea larvae bear "exceptionally long" spines on the carapace
Carapace
A carapace is a dorsal section of the exoskeleton or shell in a number of animal groups, including arthropods such as crustaceans and arachnids, as well as vertebrates such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron.-Crustaceans:In crustaceans, the...
, one directed forwards, and two directed backwards. The second zoeal stage may reach a length of 10 millimetre (0.393700787401575 in), while the megalopa has a carapace
Carapace
A carapace is a dorsal section of the exoskeleton or shell in a number of animal groups, including arthropods such as crustaceans and arachnids, as well as vertebrates such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron.-Crustaceans:In crustaceans, the...
width of 1.5 mm (0.0590551181102362 in).
Taxonomy
Pisidia longicornis was first described in 1767 by Carl Linnaeus, originally under the name Porcellana longicornis, in the 12th edition12th edition of Systema Naturae
The 12th edition of was the last edition of to be overseen by its author, Carl Linnaeus. It was published in three volumes, with parts appearing from 1766 to 1768...
of his Systema Naturae
Systema Naturae
The book was one of the major works of the Swedish botanist, zoologist and physician Carolus Linnaeus. The first edition was published in 1735...
. The specific epithet is difficult to explain, it being 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 "long-horned", from and ; it may refer to the long chelipeds (claw-bearing appendages). The species was moved from the genus Porcellana
Porcellana
Porcellana is a genus of decapod crustaceans in the widespread family Porcellanidae, the porcelain crabs, which superficially resemble true crabs...
by William Elford Leach
William Elford Leach
William Elford Leach FRS was an English zoologist and marine biologist.Leach was born at Hoe Gate, Plymouth, the son of a solicitor. At the age of twelve he went to school in Exeter, studying anatomy and chemistry. By this time he was already collecting marine samples from Plymouth Sound and along...
when he established the genus Pisidia
Pisidia (genus)
Pisidia is a genus of marine porcelain crabs, formerly included in Porcellana, comprising the following species:*Pisidia bluteli *Pisidia brasiliensis Haig, 1968*Pisidia dehaanii...
in 1820.
External links
- Pisidia longicornis British Marine Life Study Society