Clawed
lobsters comprise a
familyIn 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...
(
Nephropidae, sometimes also
Homaridae) of large marine
crustaceanCrustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
s. Highly prized as
seafoodSeafood is any form of marine life regarded as food by humans. Seafoods include fish, molluscs , crustaceans , echinoderms . Edible sea plants, such as some seaweeds and microalgae, are also seafood, and are widely eaten around the world, especially in Asia...
, lobsters are economically important, and are often one of the most profitable commodities in coastal areas they populate.
Though several groups of crustaceans are known as lobsters, the clawed lobsters are most often associated with the name. Clawed lobsters are not closely related to
spiny lobsterSpiny lobsters, also known as langouste or rock lobsters, are a family of about 45 species of achelate crustaceans, in the Decapoda Reptantia...
s or
slipper lobsterSlipper lobsters are a family of decapod crustaceans found in all warm oceans and seas. Despite their name, they are not true lobsters, but are more closely related to spiny lobsters and furry lobsters. Slipper lobsters are instantly recognisable by their enlarged antennae, which project forward...
s, which have no claws (
chelaeA chela is a pincer-like organ terminating certain limbs of some arthropods. The name comes from Greek through New Latin . The plural form is chelae. Legs bearing a chela are called chelipeds. Another name is claw because most chelae are curved and have a sharp point like a claw....
), or
squat lobsterSquat lobsters are decapod crustaceans of the families Galatheidae, Chirostylidae and Kiwaidae, including the common genera Galathea and Munida. They are not lobsters at all, but are more closely related to porcelain crabs, hermit crabs and then, more distantly, true crabs...
s. The closest relatives of clawed lobsters are the
reef lobsterReef lobsters, Enoplometopus, are a genus of small lobsters that live on reefs in the Indo-Pacific, Caribbean and warmer parts of the east Atlantic Ocean.-Description:...
s and the three families of freshwater
crayfishCrayfish, crawfish, or crawdads – members of the superfamilies Astacoidea and Parastacoidea – are freshwater crustaceans resembling small lobsters, to which they are related...
.
Evolution
The fossil record of clawed lobsters extends back at least to the
Valanginian AgeIn the geologic timescale, the Valanginian is an age or stage of the Early or Lower Cretaceous. It spans between 140.2 ± 3.0 Ma and 136.4 ± 2.0 Ma...
of the
CretaceousThe Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...
.
Description
Lobsters are
invertebrateAn invertebrate is an animal without a backbone. The group includes 97% of all animal species – all animals except those in the chordate subphylum Vertebrata .Invertebrates form a paraphyletic group...
s with a hard protective
exoskeletonAn exoskeleton is the external skeleton that supports and protects an animal's body, in contrast to the internal skeleton of, for example, a human. In popular usage, some of the larger kinds of exoskeletons are known as "shells". Examples of exoskeleton animals include insects such as grasshoppers...
. Like most
arthropodAn arthropod is an invertebrate animal having an exoskeleton , a segmented body, and jointed appendages. Arthropods are members of the phylum Arthropoda , and include the insects, arachnids, crustaceans, and others...
s, lobsters must
moltEcdysis is the moulting of the cuticula in many invertebrates. This process of moulting is the defining feature of the clade Ecdysozoa, comprising the arthropods, nematodes, velvet worms, horsehair worms, rotifers, tardigrades and Cephalorhyncha...
in order to grow, which leaves them vulnerable. During the molting process, several species change color. Lobsters have 10 walking legs; the front three pairs bear claws, the first of which are larger than the others. Although, like most other arthropods, lobsters are largely bilaterally symmetrical, they often possess unequal, specialized claws, like the
king crabKing crabs, also called stone crabs, are a superfamily of crab-like decapod crustaceans chiefly found in cold seas. Because of their large size and the taste of their meat, many species are widely caught and sold as food, the most common being the red king crab, Paralithodes camtschaticus.King...
.
Lobster anatomy includes the
cephalothoraxThe cephalothorax is a tagma of various arthropods, comprising the head and the thorax fused together, as distinct from the abdomen behind. The word cephalothorax is derived from the Greek words for head and thorax...
which fuses the head and the
thoraxThe thorax is a division of an animal's body that lies between the head and the abdomen.-In tetrapods:...
, both of which are covered by a
chitinChitin n is a long-chain polymer of a N-acetylglucosamine, a derivative of glucose, and is found in many places throughout the natural world...
ous
carapaceA 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...
, and the abdomen. The lobster's head bears
antennaeAntennae in biology have historically been paired appendages used for sensing in arthropods. More recently, the term has also been applied to cilium structures present in most cell types of eukaryotes....
, antennules,
mandiblesthumb|250px|The mandibles of a [[Bull ant]]The mandible of an arthropod is either of a pair of mouthparts used for biting, cutting and holding food. Mandibles are often simply referred to as jaws. Mandibles are present in the extant subphyla Myriapoda , Crustacea and Hexapoda...
, the first and second
maxillaeIn arthropods, the maxillae are paired structures present on the head as mouthparts in members of the clade Mandibulata, used for tasting and manipulating food. Embryologically, the maxillae are derived from the 4th and 5th segment of the head and the maxillary palps; segmented appendages extending...
, and the first, second, and third maxillipeds. Because lobsters live in a murky environment at the bottom of the ocean, they mostly use their antennae as sensors. The lobster eye has a reflective structure above a convex retina. In contrast, most complex eyes use refractive ray concentrators (lenses) and a concave retina. The abdomen includes
swimmeretsThe decapod crustacean, such as a crab, lobster, shrimp or prawn, is made up of nineteen body segments grouped into two main body parts, the cephalothorax and the abdomen. Each segment may possess one pair of appendages, although in various groups these may be reduced or missing...
and its tail is composed of uropods and the
telsonThe telson is the last division of the body of a crustacean. It is not considered a true segment because it does not arise in the embryo from teloblast areas as do real segments. It never carries any appendages, but a forked "tail" called the caudal furca is often present. Together with the...
.
Lobsters, like snails and spiders, have blue blood due to the presence of haemocyanin which contains
copperCopper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...
(in contrast, vertebrates and many other animals have red blood from
ironIron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...
-rich haemoglobin). Lobsters possess a green
hepatopancreasThe hepatopancreas, digestive gland or midgut gland is an organ of the digestive tract of arthropods, molluscs and fish. It provides the functions which in mammals are provided separately by the liver and pancreas, including the production of digestive enzymes, and absorption of digested...
, called the
tomalleyTomalley or lobster paste is the soft, green substance found in the body cavity of lobsters, that fulfills the functions of both the liver and the pancreas. Tomalley corresponds to the hepatopancreas in other arthropods...
by chefs, which functions as the animal's
liverThe liver is a vital organ present in vertebrates and some other animals. It has a wide range of functions, including detoxification, protein synthesis, and production of biochemicals necessary for digestion...
and
pancreasThe pancreas is a gland organ in the digestive and endocrine system of vertebrates. It is both an endocrine gland producing several important hormones, including insulin, glucagon, and somatostatin, as well as a digestive organ, secreting pancreatic juice containing digestive enzymes that assist...
.
In general, lobsters are 25–50 cm (9.8–19.7 ) long, and move by slowly walking on the sea floor. However, when they flee, they swim backwards quickly by curling and uncurling their
abdomenIn vertebrates such as mammals the abdomen constitutes the part of the body between the thorax and pelvis. The region enclosed by the abdomen is termed the abdominal cavity...
. A speed of 5 metres per second (11.2 mph) has been recorded. This is known as the
caridoid escape reactionThe Caridoid Escape Reaction, also known as lobstering or tail-flipping, refers to an innate escape mechanism in marine and freshwater crustaceans such as lobsters, krill, shrimp and crayfish....
.
Longevity
Recent research suggests that lobsters may not slow down, weaken, or lose fertility with age. In fact, older lobsters are more fertile than younger lobsters. This longevity may be due to
telomeraseTelomerase is an enzyme that adds DNA sequence repeats to the 3' end of DNA strands in the telomere regions, which are found at the ends of eukaryotic chromosomes. This region of repeated nucleotide called telomeres contains non-coding DNA material and prevents constant loss of important DNA from...
, an
enzymeEnzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
that repairs
DNA sequenceThe sequence or primary structure of a nucleic acid is the composition of atoms that make up the nucleic acid and the chemical bonds that bond those atoms. Because nucleic acids, such as DNA and RNA, are unbranched polymers, this specification is equivalent to specifying the sequence of...
s of the form "TTAGGG". This sequence is often referred to as the telomeres of the DNA. It has been argued that lobsters may exhibit
negligible senescenceNegligible senescence refers to the failure of a few select animals to display symptoms of aging. More specifically, negligibly senescent animals do not have measurable reductions in their reproductive capability with age, or measurable functional decline with age. Death rates in negligibly...
and some scientists have claimed that they could effectively live indefinitely, barring injury, disease, capture, etc. Their longevity allows them to reach impressive sizes. According to the
Guinness World RecordsGuinness World Records, known until 2000 as The Guinness Book of Records , is a reference book published annually, containing a collection of world records, both human achievements and the extremes of the natural world...
, the largest lobster was caught in
Nova ScotiaNova Scotia is one of Canada's three Maritime provinces and is the most populous province in Atlantic Canada. The name of the province is Latin for "New Scotland," but "Nova Scotia" is the recognized, English-language name of the province. The provincial capital is Halifax. Nova Scotia is the...
,
CanadaCanada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
, and weighed 20.15 kilograms (44.4 lb).
Symbion
Animals of the genus
SymbionSymbion is the name of a genus of aquatic animals, less than ½ mm wide, found living attached to the bodies of cold-water lobsters. They have sac-like bodies, and three distinctly different forms in different parts of their two-stage life-cycle...
, the only member of the animal phylum Cycliophora, live exclusively on lobster
gillA gill is a respiratory organ found in many aquatic organisms that extracts dissolved oxygen from water, afterward excreting carbon dioxide. The gills of some species such as hermit crabs have adapted to allow respiration on land provided they are kept moist...
s and mouthparts.
Ecology
Lobsters are found in all oceans. They live on rocky, sandy, or muddy bottoms from the shoreline to beyond the edge of the
continental shelfThe continental shelf is the extended perimeter of each continent and associated coastal plain. Much of the shelf was exposed during glacial periods, but is now submerged under relatively shallow seas and gulfs, and was similarly submerged during other interglacial periods. The continental margin,...
. They generally live singly in crevices or in burrows under rocks.
Lobsters are omnivores and typically eat live prey such as fish, mollusks, other crustaceans, worms, and some plant life. They scavenge if necessary, and may resort to
cannibalismIn zoology, cannibalism is the act of one individual of a species consuming all or part of another individual of the same species as food. Cannibalism is a common ecological interaction in the animal kingdom and has been recorded for more than 1500 species...
in captivity; however, this has not been observed in the wild. Although lobster skin has been found in lobster stomachs, this is because lobsters eat their shed skin after
moltingEcdysis is the moulting of the cuticula in many invertebrates. This process of moulting is the defining feature of the clade Ecdysozoa, comprising the arthropods, nematodes, velvet worms, horsehair worms, rotifers, tardigrades and Cephalorhyncha...
.
Gastronomy
Lobster recipes include
Lobster NewbergLobster Newburg is an American seafood dish made from lobster, butter, cream, cognac, sherry, eggs, and Cayenne pepper. The dish was invented by Ben Wenberg, a sea captain in the fruit trade. He demonstrated the dish at Delmonico’s Restaurant in New York City to the manager, Charles Delmonico, in...
and
Lobster ThermidorLobster Thermidor is a French dish consisting of a creamy mixture of cooked lobster meat, egg yolks, and cognac or brandy, stuffed into a lobster shell, and optionally served with an oven-browned cheese crust, typically Gruyère...
. Lobster is used in soup,
bisqueBisque is a smooth, creamy, highly-seasoned soup of French origin, classically based on a strained broth of crustaceans. It can be made from lobster, crab, shrimp or crayfish...
,
lobster rollA lobster roll is a kind of sandwich filled with lobster meat. A traditional lobster roll contains the fresh cooked meat of a lobster, tossed with mayonnaise and served on a grilled hot dog bun or similar roll, so that the opening is on the top rather than on the side...
s, and
cappon magroCappon magro or capòn magro is an elaborate and rich Genoese salad of seafood and vegetables over hard tack arranged into a decorative pyramid and dressed with a rich sauce....
. Lobster meat may be dipped in
clarified butterClarified butter is milk fat rendered from butter to separate the milk solids and water from the butterfat. Typically, it is produced by melting butter and allowing the different components to separate by density...
, resulting in a sweetened flavour.
Cooks boil or steam live lobsters. The lobster cooks for seven minutes for the first pound and three minutes for each additional pound.
According to the United States
Food and Drug AdministrationThe Food and Drug Administration is an agency of the United States Department of Health and Human Services, one of the United States federal executive departments...
(FDA), the mean level of
mercuryMercury is a chemical element with the symbol Hg and atomic number 80. It is also known as quicksilver or hydrargyrum...
in
American lobsterThe American lobster, Homarus americanus, is a species of lobster found on the Atlantic coast of North America, chiefly from Labrador to New Jersey. Within North America, it is also known as the northern lobster or Maine lobster. It can reach a body length of , and a mass of over , making it the...
is 0.31 ppm.
History
In North America, the American lobster did not achieve popularity until the mid-19th century, when New Yorkers and Bostonians developed a taste for it, and commercial lobster fisheries only flourished after the development of the lobster smack. Prior to this time, lobster was considered a mark of poverty or as a food for indentured servants or lower members of society in
MaineMaine is a state in the New England region of the northeastern United States, bordered by the Atlantic Ocean to the east and south, New Hampshire to the west, and the Canadian provinces of Quebec to the northwest and New Brunswick to the northeast. Maine is both the northernmost and easternmost...
,
MassachusettsThe Commonwealth of Massachusetts is a state in the New England region of the northeastern United States of America. It is bordered by Rhode Island and Connecticut to the south, New York to the west, and Vermont and New Hampshire to the north; at its east lies the Atlantic Ocean. As of the 2010...
and the Canadian
MaritimesThe Maritime provinces, also called the Maritimes or the Canadian Maritimes, is a region of Eastern Canada consisting of three provinces, New Brunswick, Nova Scotia, and Prince Edward Island. On the Atlantic coast, the Maritimes are a subregion of Atlantic Canada, which also includes the...
, and servants specified in employment agreements that they would not eat lobster more than twice per week. American lobster was initially deemed worthy only of being used as
fertilizerFertilizer is any organic or inorganic material of natural or synthetic origin that is added to a soil to supply one or more plant nutrients essential to the growth of plants. A recent assessment found that about 40 to 60% of crop yields are attributable to commercial fertilizer use...
or fish bait, and it was not until well into the twentieth century that it was viewed as more than a low-priced canned staple food.
Caught lobsters are graded as new-shell, hard-shell and old-shell and, because lobsters that have recently shed their shells are the most delicate, there is an inverse relationship between the price of American lobster and its flavor. New-shell lobsters have paper-thin shells and a worse meat-to-shell ratio, but what meat exists is very sweet. However, the lobsters are so delicate that even transport to Boston almost kills them, making the market for new-shell lobsters strictly local to the fishing towns where they are offloaded. Hard-shell lobsters with firm shells but with less sweet meat can survive shipping to Boston, New York and even Los Angeles so they command a higher price than new-shell lobsters. Meanwhile, old-shell lobsters, which have not shed since the previous season and have a coarser flavor, can be air-shipped anywhere in the world and arrive alive, making them the most expensive. One seafood guide notes that an eight dollar lobster dinner at a restaurant overlooking fishing piers in Maine is consistently delicious, while "the eighty-dollar lobster in a three-star Paris restaurant is apt to be as much about presentation as flavor".
Animal welfare issues
The most common way of killing a lobster is by placing it live in boiling water (with or without spending a period of time in a freezer) or by splitting it by severing the body in half lengthwise. Lobsters may also be killed or rendered insensate immediately before boiling through a stab into the brain, in the belief that this will stop suffering. However, a lobster's brain operates from not one but several
gangliaIn anatomy, a ganglion is a biological tissue mass, most commonly a mass of nerve cell bodies. Cells found in a ganglion are called ganglion cells, though this term is also sometimes used to refer specifically to retinal ganglion cells....
and disabling only the frontal ganglion does not usually result in death or unconsciousness. The boiling method is illegal in some places, such as in
Reggio EmiliaReggio Emilia is an affluent city in northern Italy, in the Emilia-Romagna region. It has about 170,000 inhabitants and is the main comune of the Province of Reggio Emilia....
, Italy, where offenders face fines of up to
€The euro is the official currency of the eurozone: 17 of the 27 member states of the European Union. It is also the currency used by the Institutions of the European Union. The eurozone consists of Austria, Belgium, Cyprus, Estonia, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg,...
495.
Fishery and aquaculture
Lobsters are caught using
baited, one-way trapsNot to be confused with Lobster-tailed potA lobster trap or lobster pot is a portable trap that traps lobsters or crayfish and is used in lobster fishing. A lobster trap can hold several lobsters. Lobster traps are constructed of wire and wood. An opening permits the lobster to enter a tunnel of...
with a color-coded marker buoy to mark cages. Lobster is fished in water between 1 and 500 fathom (1.8 and 914.4 m), although some lobsters live at 2000 fathoms (3,657.6 m). Cages are of plastic-coated galvanized steel or wood. A lobster fisher may tend as many as 2,000 traps. Around the year 2000, due to overfishing and high demand, lobster
aquacultureAquaculture, also known as aquafarming, is the farming of aquatic organisms such as fish, crustaceans, molluscs and aquatic plants. Aquaculture involves cultivating freshwater and saltwater populations under controlled conditions, and can be contrasted with commercial fishing, which is the...
expanded. As of 2008, no lobster aquaculture operation had achieved commercial success.
Species
This list contains all extant species in the family Nephropidae:
- Acanthacaris caeca
Acanthacaris is a genus of lobsters and the only genus in the family Neophoberinae. They are relatively large lobsters with a cylindrical body covered with sharp spines . The carapace has a well-developed rostrum. The eyes are very small and lack pigment, while the antennae are long and whiplike....
- Acanthacaris tenuimana
Acanthacaris is a genus of lobsters and the only genus in the family Neophoberinae. They are relatively large lobsters with a cylindrical body covered with sharp spines . The carapace has a well-developed rostrum. The eyes are very small and lack pigment, while the antennae are long and whiplike....
- Eunephrops bairdii
Eunephrops bairdii is a species of marine lobster, commonly called the "red lobster", endemic to the Caribbean Sea. It is found off the coasts of Colombia and Panama at depths of . It reaches a length of up to , which is equivalent to a carapace length of , but is apparently too scarce for...
- Eunephrops cadenasi
Eunephrops cadenasi, sometimes called the sculptured lobster, is a species of lobster found in the Caribbean.-Description:Eunephrops cadenasi is a medium-sized lobster with a cylindrical body. Adult male individuals of Eunephrops cadenasi reach a total length of , and a carapace length of , while...
- Eunephrops luckhursti
- Eunephrops manningi
Eunephrops manningi, the banded lobster, is a species of lobster found in the Florida Straits and off the coast of Anguilla. It was named in 1974 by Lipke Holthuis after his good friend Raymond B. Manning. It grows to a length of and lives at depths of...
- Homarinus capensis
The Cape lobster, Homarinus capensis, is a small lobster that lives off the coast of South Africa, between Cape Town and East London...
– Cape lobster
- Homarus americanus
The American lobster, Homarus americanus, is a species of lobster found on the Atlantic coast of North America, chiefly from Labrador to New Jersey. Within North America, it is also known as the northern lobster or Maine lobster. It can reach a body length of , and a mass of over , making it the...
– American lobster
- Homarus gammarus – European lobster
- Metanephrops andamanicus – Andaman lobster
- Metanephrops arafurensis
- Metanephrops armatus
Metanephrops is a genus of lobsters, commonly known as scampi. Important species for fishery include Metanephrops australiensis and Metanephrops challengeri...
- Metanephrops australiensis
Metanephrops australiensis, commonly known as Australian scampi, is a species of lobster. It is found off the north-west coast of Western Australia, ranging from the city of Eucla to Indonesia. It is prolific near Port Hedland....
– Australian scampi
- Metanephrops binghami
Metanephrops binghami, the Caribbean lobster or Caribbean lobsterette, is a lobster which inhabits the western Atlantic region: from the Bahamas and southern Florida to French Guiana, including the Gulf of Mexico and the Caribbean Sea....
– Caribbean lobster
- Metanephrops boschmai – bight lobster
- Metanephrops challengeri
Metanephrops challengeri is a species of lobster from New Zealand. It was first collected by the Challenger expedition of 1872–1876, but only described as separate from related species by Heinrich Balss in 1914...
– New Zealand scampi
- Metanephrops formosanus
- Metanephrops japonicus
Metanephrops japonicus is a species of lobster found in Japanese waters, and a gourmet food in Japanese cuisine. It occurs from Chōshi, Chiba Prefecture to the east coast of Kyushu, where it lives at depths of . Adults grow to a total length of , and a carapace length of ....
– Japanese lobster
- Metanephrops mozambicus
- Metanephrops neptunus
- Metanephrops rubellus
- Metanephrops sagamiensis
- Metanephrops sibogae
- Metanephrops sinensis – China lobster
- Metanephrops thomsoni
- Metanephrops velutinus
- Nephropides caribaeus
- Nephrops norvegicus – Norway lobster
- Nephropsis acanthura
- Nephropsis aculeata – Florida lobsterette
- Nephropsis agassizii
- Nephropsis atlantica
Nephropsis atlantica, sometimes called the scarlet lobsterette or scarlet clawed lobster, is a species of lobster from the Atlantic Ocean.-Description:...
- Nephropsis carpenteri
- Nephropsis ensirostris
- Nephropsis hamadai
- Nephropsis holthuisii
- Nephropsis macphersoni
- Nephropsis malhaensis
- Nephropsis neglecta
- Nephropsis occidentalis
- Nephropsis rosea
Nephropsis rosea, sometimes called the rosy lobsterette or two-toned lobsterette, is a species of lobster.It is found in the Caribbean Sea and Gulf of Mexico, and as far north in the western Atlantic Ocean as Bermuda, and as far south as Guiana. It mostly lives at depths of , but has been observed...
- Nephropsis serrata
- Nephropsis stewarti
- Nephropsis suhmi
- Nephropsis sulcata
- Thymopides grobovi
- Thymops birsteini
Thymops birsteini, the Patagonian lobsterette, is a species of lobster found around the coasts of South America, particularly the South Atlantic. It belongs to the monotypic genus Thymops.-Distribution:...
- Thymopsis nilenta
Thymopsis nilenta is a species of lobster, and the only species in the genus Thymopsis. It is found around the Falkland Islands and South Georgia at depths of . It reaches a total length of , of which the carapace is about . It is known from a total of four specimens collected from two...
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