"traps, sometimes referred to as ""pots"", have a buoy floating on the surface, and lobstermen check their traps between one and seven days after setting them. The inefficiency of the trapping system has inadvertently prevented the lobster population from being overfished. Lobsters can easily escape the trap, and will defend the trap against other lobsters because it is a source of food. An estimated 10% of lobsters that encounter a trap enter, and of those that enter 6% will be caught. In the United States, the lobster industry is regulated. Every lobster fisher is required to use a lobster gauge"
"leaves them vulnerable. During the moulting process, several species change colour. Lobsters have 8 walking legs; the front three pairs bear claws, the first of which are larger than the others. Although lobsters are largely bilaterally symmetrical like most other arthropods, some genera possess unequal, specialised claws. Lobster anatomy includes the cephalothorax which fuses the head and the thorax, both of which are covered by a chitinous carapace, and the abdomen. The lobster's head bears antennae, antennules, mandibles, the first and second maxillae, and the first, second, and third maxillipeds. Because lobsters live in murky environments at the bottom of"
"Lobster Lobsters comprise a family (Nephropidae, sometimes also Homaridae) of large marine crustaceans. Lobsters have long bodies with muscular tails, and live in crevices or burrows on the sea floor. Three of their five pairs of legs have claws, including the first pair, which are usually much larger than the others. Highly prized as seafood, lobsters are economically important, and are often one of the most profitable commodities in coastal areas they populate. Commercially important species include two species of ""Homarus"" (which looks more like the stereotypical lobster) from the northern Atlantic Ocean, and scampi (which looks more like a"
"complex invertebrates such as lobsters. This animal usually grows to one cm in length, though individuals as long as four centimeters have been reported. Its nervous system consists of a nerve net with no defined brain or ganglia. This animal lacks an anus, excreting waste through the same opening as it intakes food. The animal moves through the water via rhythmic muscle contraction, aided by the motion of numerous tiny cilia on its sides, and a tuft of longer cilia on its back. Small cells contain vesicles which may act as glands. Adults are known to have a symbiotic relationship"
"caused by the disappearance of many of the Maine lobsters' natural predators. In general, lobsters are long, and move by slowly walking on the sea floor. However, when they flee, they swim backward quickly by curling and uncurling their abdomens. A speed of has been recorded. This is known as the caridoid escape reaction. Symbiotic animals of the genus ""Symbion"", the only member of the phylum Cycliophora, live exclusively on lobster gills and mouthparts. Different species of ""Symbion"" have been found on the three commercially important lobsters of the North Atlantic Ocean – ""Nephrops norvegicus"", ""Homarus gammarus"", and ""Homarus americanus""."
"steel or wood. A lobster fisher may tend as many as 2,000 traps. Around year 2000, owing to overfishing and high demand, lobster aquaculture expanded. As of 2008, no lobster aquaculture operation had achieved commercial success, mainly because lobsters eat each other (cannibalism) and the growth of the species is slow. The fossil record of clawed lobsters extends back at least to the Valanginian age of the Cretaceous (140 million years ago). This list contains all extant species in the family Nephropidae: Lobster Lobsters comprise a family (Nephropidae, sometimes also Homaridae) of large marine crustaceans. Lobsters have long bodies with"
"Slipper lobster Slipper lobsters are a family (Scyllaridae) of about 90 species of achelate crustaceans, in the Decapoda Reptantia, found in all warm oceans and seas. 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 from the head as wide plates. All the species are edible, and some, such as the Moreton Bay bug and the Balmain bug (""Ibacus peronii"") are of commercial importance. Slipper lobsters have six segments in their heads and eight segments in the thorax, which are collectively"
"move on many more legs. Terrestrial crustaceans may have a fair number – woodlice having fourteen legs. Also, as previously mentioned, some insect larvae such as caterpillars and sawfly larvae have up to five (caterpillars) or nine (sawflies) additional fleshy prolegs in addition to the six legs normal for insects. Some species of invertebrate have even more legs, the unusual velvet worm having stubby legs under the length of its body, with around several dozen pairs of legs. Centipedes have one pair of legs per body segment, with typically around 50 legs, but some species have over 200. The terrestrial"
"micrograms (millionths of a gram), while the heaviest weigh over . Some living crustaceans are much larger; for example, the legs of the Japanese spider crab may span up to , with the heaviest of all living arthropods being the American lobster, topping out at over 20 kg (44 lbs). The embryos of all arthropods are segmented, built from a series of repeated modules. The last common ancestor of living arthropods probably consisted of a series of undifferentiated segments, each with a pair of appendages that functioned as limbs. However, all known living and fossil arthropods have grouped segments into"
"the Achelata. Genera of spiny lobsters include ""Palinurus"" and a number of anagrams thereof: ""Panulirus"", ""Linuparus"", ""etc."" (Palinurus was also a helmsman in Virgil's ""Æneid"".) In total, 12 extant genera are recognised, containing around 60 living species: Although they superficially resemble true lobsters in terms of overall shape and having a hard carapace and exoskeleton, the two groups are not closely related. Spiny lobsters can be easily distinguished from true lobsters by their very long, thick, spiny antennae, by the lack of chelae (claws) on the first four pairs of walking legs, although the females of most species have a"
"live in crevices of rocks and coral reefs, only occasionally venturing out at night to seek snails, clams, sea-hares, crabs, or sea urchins to eat. Sometimes, they migrate in very large groups in long files of lobsters across the sea floor. These lines may be more than 50 lobsters long. Spiny lobsters navigate using the smell and taste of natural substances in the water that change in different parts of the ocean. It was recently discovered that spiny lobsters can also navigate by detecting the Earth's magnetic field. They keep together by contact, using their long antennae. Potential predators may"
"of Northern Europe, recently reaching the United Kingdom. It has also spread southwards as far as the Danube in Serbia. ""Orconectes limosus"" can reproduce sexually or by parthenogenesis. Lobsters and Crayfish are decapods meaning that they have 10 legs. 2 of them are claws. These Crayfish live on the bottom of the freshwater pools, such as lakes, ponds and swamps. They prefer flat, sandy, and rocky floors. They are also found outside the water on beaches or lawns near the pool of water. They use rocks to make burrows while in the water. This is a very common species of"
"survive to the juvenile stage. To reach the fourth stage – the post-larva – the larva undergoes metamorphosis, and subsequently shows a much greater resemblance to the adult lobster, is around long, and swims with its pleopods. At this stage, the lobster's claws are still relatively small so they rely primarily on tail-flip escapes if threatened. After the next molt, the lobster sinks to the ocean floor, and adopts a benthic lifestyle. It molts more and more infrequently, from an initial rate of ten times per year to once every few years. After one year, it is around long, and"
"crustacean which resembles a shrimp tends to be called one. They swim forward by paddling with swimmerets on the underside of their abdomens, although their escape response is typically repeated flicks with the tail driving them backwards very quickly. Crabs and lobsters have strong walking legs, whereas shrimp have thin, fragile legs which they use primarily for perching. Shrimp are widespread and abundant. There are thousands of species adapted to a wide range of habitats. They can be found feeding near the seafloor on most coasts and estuaries, as well as in rivers and lakes. To escape predators, some species"
"lobster is one of the largest spiny lobster species, and grows up to long, but does not usually exceed . Males can weigh up to ., with the record being a 16 lbs., 1 oz. male caught off Catalina island in 1968. The upper side of the animal is brownish red, without the paler bands or spots seen in some other spiny lobsters. The legs are a similar color, but with one or more lighter streaks running along their length. Males and females of all ages can be distinguished by the position of the two round genital openings or gonopores."
"small claw on the fifth pair, and by a particularly specialized larval phase called phyllosoma. True lobsters have much smaller antennae and claws on the first three pairs of legs, with the first being particularly enlarged. Spiny lobsters have typically a slightly compressed carapace, lacking any lateral ridges. Their antennae lack a scaphocerite, the flattened exopod of the antenna. This is fused to the epistome (a plate between the labrum and the basis of the antenna). The flagellum, at the top of the antenna, is stout, tapering, and very long. The ambulatory legs (pereopods) end in claws (chelae). The fossil"
"butterflies do not use the front legs for walking. Arachnids have eight legs. Most arachnids lack extensor muscles in the distal joints of their appendages. Spiders and whipscorpions extend their limbs hydraulically using the pressure of their hemolymph. Solifuges and some harvestmen extend their knees by the use of highly elastic thickenings in the joint cuticle. Scorpions, pseudoscorpions and some harvestmen have evolved muscles that extend two leg joints (the femur-patella and patella-tibia joints) at once. The scorpion ""Hadrurus arizonensis"" walks by using two groups of legs (left 1, right 2, Left 3, Right 4 and Right 1, Left 2,"
"not native to Singapore, but are commonly found as pets, or as an invasive species (""Cherax quadricarinatus"") in the many water catchment areas, and are alternatively known as ""freshwater lobsters"". The body of a decapod crustacean, such as a crab, lobster, or prawn (shrimp), is made up of twenty 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. On average, crayfish grow to in length, but some grow larger. Walking legs have a small claw at the end."
"of California. With individuals possessing up to 750 legs (375 pairs), ""Illacme"" has more legs than any animal known. Loomis later described another species from Panama with 700 legs. Loomis' specialty was in the millipedes of Central America and the Caribbean, and over his career he named more than 500 species, at least 127 new genera, 2 new subfamilies, and 9 new families, including Messicobolidae, Tingupidae, and Tridontomidae, with only a few taxa named with co-authors. He produced 64 scientific papers on arthropods and 50 on millipedes. The eminent myriapodologist Richard L. Hoffman wrote of Loomis: ""(H)is monographs on the"
"animals with the most legs are the millipedes. They have two pairs of legs per body segment, with common species having between 80 and 400 legs overall – with the rare species ""Illacme plenipes"" having up to 750 legs. Animals with many legs typically move them in metachronal rhythm, which gives the appearance of waves of motion travelling forwards along their rows of legs. The legs of tetrapods, the main group of terrestrial vertebrates, have internal bones, with externally attached muscles for movement, and the basic form has three key joints: the shoulder joint, the knee joint, and the ankle"
"the legs and in the arms that connect the large claws to the body. There is also some small amount of meat just below the carapace around the thorax and in the smaller legs. Most lobsters come from the northeastern coast of North America, with the Atlantic Provinces of Canada and the U.S. state of Maine being the largest producers. They are caught primarily using lobster traps, although lobsters are also harvested as bycatch by bottom trawlers, fishermen using gillnets, and by scuba divers in some areas. Maine completely prohibits scuba divers from catching lobsters (violations could result in up"
"esteemed food, and is widely caught using lobster pots, mostly around the British Isles. ""Homarus gammarus"" is a large crustacean, with a body length up to and weighing up to , although the lobsters caught in lobster pots are usually long and weigh . Like other crustaceans, lobsters have a hard exoskeleton which they must shed in order to grow, in a process called ecdysis (moulting). This may occur several times a year for young lobsters, but decreases to once every 1–2 years for larger animals. The first pair of pereiopods is armed with a large, asymmetrical pair of feet."
"covered in a thick carapace. The six segments of the abdomen each bear a pair of pleopods, while the thoracic appendages are either walking legs or maxillipeds. The head segments bear various mouthparts and two pairs of antennae. The first antennae, or ""antennules"", are held on a long flexible stalk, and are used for sensing the environment. The second antennae are the slipper lobsters' most conspicuous feature, as they are expanded and flattened into large plates that extend horizontally forward from the animal's head. There is considerable variation in size among species of slipper lobsters. The Mediterranean species ""Scyllarus pygmaeus"""
"varies between the sexes. In females, the first one or two pairs are missing, while the remaining pairs are uniramous, and have long setae, to which the eggs can be attached. In males, the first two pairs are formed into gonopods, and are used to transfer the spermatophore to the female during mating; the first pair is often missing. The remaining pleopods can be similar to those of the females, or reduced in size, or entirely absent. In both sexes, the uropods are biramous. The majority of squat lobsters are benthic, spending their lives on the sea-floor. A few, however,"
"the tarsus. The claws of the scorpion are not truly legs, but are pedipalps, a different kind of appendage that is also found in spiders and is specialised for predation and mating. In ""Limulus"", there are no metatarsi or pretarsi, leaving six segments per leg. The legs of crustaceans are divided primitively into seven segments, which do not follow the naming system used in the other groups. They are: coxa, basis, ischium, merus, carpus, propodus, and dactylus. In some groups, some of the limb segments may be fused together. The claw of a lobster or crab is formed by the"
"is the smallest, growing to a maximum total length of , and rarely more than . The largest species, ""Scyllarides haanii"", may reach long. Slipper lobsters are typically bottom dwellers of the continental shelves, found at depths of up to . Slipper lobsters eat a variety of molluscs, including limpets, mussels and oysters, as well as crustaceans, polychaetes and echinoderms. They grow slowly and live to a considerable age. They lack the giant neurones which allow other decapod crustaceans to perform tailflips, and must rely on other means to escape predator attack, such as burial in a substrate and reliance"
"Stenopodidea The Stenopodidea is a small group of decapod crustaceans. Often confused with shrimp or prawns, they are neither, but belong in a group closer to the reptant decapods, such as lobsters and crabs. They may be easily recognised by their third pereiopod (walking leg), which is greatly enlarged. In the lobsters and crabs, it is the first pereiopod that is much bigger than the others. There are 71 extant species currently recognised, divided into 12 genera. Three fossil species are also recognised, each belonging to a separate genus. The earliest fossil assigned to the Stenopodidea is ""Devonostenopus pennsylvaniensis"" from"
"to a maximum length of about , but a more normal length is , with males growing to larger sizes than females. There is a group of four strong spines joined at the base, attached to the plate immediately in front of the carapace to which the antennules are attached. The colour of this spiny lobster is variable, ranging from yellowish-green to rusty-brown or bluish-black. There are small white spots on the carapace and abdomen and a pair of larger white spots near the outer edge of the first abdominal segment. The legs are dark green or red with yellow"
"articulation of the dactylus against an outgrowth of the propodus. Crustacean limbs also differ in being biramous, whereas all other extant arthropods have uniramous limbs. Myriapods (millipedes, centipedes and their relatives) have seven-segmented walking legs, comprising coxa, trochanter, prefemur, femur, tibia, tarsus, and a tarsal claw. Myriapod legs show a variety of modifications in different groups. In all centipedes, the first pair of legs is modified into a pair of venomous fangs called forcipules. In most millipedes, one or two pairs of walking legs in adult males are modified into sperm-transferring structures called gonopods. In some millipedes, the first leg"
"of legs per segment. Around 12,000 species have been described, which may represent less than a tenth of the true global millipede diversity. The name ""millipede"" is a compound word formed from the Latin roots ""millia"" (""thousand"") and ""pes"" (gen. ""pedis"") (""foot""), although millipedes typically have between 36 and 400 legs. One species, ""Illacme plenipes"", has the greatest number of legs of any animal, with 750. Pill millipedes are much shorter, and are capable of rolling up into a ball, like pillbugs. About 200 species of them are known worldwide. They resemble centipedes but are smaller and translucent. Many spend"
"the longest larval development known for any marine creature. The ""phyllosoma"" (Greek for ""leaf-like"") larvae spend between 9 months to 2 years in oceanic waters before metamorphosing to the post larval stage, known as the puerulus, which then swims towards the coast to settle. Maximum total body length is 58 cm (males), and 43 cm (females); maximum carapace lengths 23.5 cm (males), 18 cm (females); minimum legal carapace lengths 10 cm (males), and 9 cm (females). The potential for ""Jasus edwardsii"" to become an aquaculture species in New Zealand is high. Although not commercially farmed yet, this species of lobster"
"of the legs, which makes a sidelong gait more efficient. However, some crabs walk forwards or backwards, including raninids, ""Libinia emarginata"" and ""Mictyris platycheles"". Some crabs, notably the Portunidae and Matutidae, are also capable of swimming, the Portunidae especially so as their last pair of walking legs are flattened into swimming paddles. A stomatopod, ""Nannosquilla decemspinosa"", can escape by rolling itself into a self-propelled wheel and somersault backwards at a speed of 72 rpm. They can travel more than 2 m using this unusual method of locomotion. ""Velella"", the by-the-wind sailor, is a cnidarian with no means of propulsion other"
"at least two types of octopus walk bipedally on the sea floor using two of their arms, so they can use the remaining arms to camouflage themselves as a mat of algae or floating coconut. There are no three-legged animals—though some macropods, such as kangaroos, that alternate between resting their weight on their muscular tails and their two hind legs, could be looked at as an example of tripedal locomotion in animals. Many familiar animals are quadrupedal, walking or running on four legs. A few birds use quadrupedal movement in some circumstances. For example, the shoebill sometimes uses its wings"