..... Click the link for more information. with five pairs of jointed legs, the first bearing large pincerlike claws of unequal size adapted to crushing the shells of its prey. The segmented body of the lobster consists of a large cephalothorax (made up of 14 segments) and a moveable, muscular abdomen (composed of 7 segments). It is covered with a chitinous exoskeleton that is dark green in the living animal and bright red when boiled. As the lobster grows, the exoskeleton is periodically molted and a new, larger one is formed in its place. Lobsters have 20 pairs of gills attached to the bases of the legs and to the sides of the body; the gills are protected by the carapace, the large area of the exoskeleton covering the back and sides of the cephalothorax. In addition to the legs, the appendages consist of 2 paired antennae, 6 pairs of mouth parts, and the small swimmerets attached to the abdominal segments. In the female the eggs remain attached to the swimmerets for 10 or 11 months until they hatch into free-swimming larvae. The larvae swim for about a year, molting between 14 and 17 times before they settle to the bottom and begin to take on adult characteristics. Lobsters crawl briskly over the ocean floor and swim backward with great speed by scooping motions of the muscular abdomen and tail, but are clumsy on land. They are scavengers but also prey on shellfish and may even attack live fish and large gastropods. Over a period of five years they grow to an average weight of 3 lb (1.4 kg). The common American lobster, Homarus americanus, is found inshore in summer and in deeper waters in winter from Labrador to North Carolina, but especially along the New England coast, where the chief lobster fisheries are located. Lobsters are caught in slatted wooden traps, or "pots," baited with dead fish. In Europe a species of Homarus similar to the American is found, but the smaller Norway lobster is the chief seafood variety. The spiny, or rock, lobsters, found in warm seas of both hemispheres, are actually marine crayfish (genus Panulirus); they lack claws but have sharp spines on the carapace. The stout-bodied, sometimes brightly colored squat lobsters are close relatives of the hermit crab; their broad abdomens are usually tucked under their bodies, as in crabs, but can be extended and used for backward swimming, as in the true lobsters. Lobsters are protected by law and are raised by several hatcheries on the New England coast; nevertheless, they are still in danger of extinction. Lobsters are classified in the phylum Arthropoda Arthropoda [Gr.,=jointed feet], largest and most diverse animal phylum. The arthropods include crustaceans, insects, centipedes, millipedes, symphylans, pauropodans, and the extinct trilobites.
..... Click the link for more information. , subphylum Crustacea, order Decapoda, family Homaridae.
lobster
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lobster
lobster [′läb·stər]
Lobster
any one marine decapod of the genera Homarus and Nephrops. The former genus comprises three species: the European lobster (H. vulgaris), the American lobster (H. americanus), and the cape lobster (H. capensis). The genus Nephrops includes 13 tropical and warm-water species, as well as the Norway lobster (N. norvegicus).
In structure, lobsters are similar to crayfish: the cephalothorax has a sharp frontal outgrowth, the abdomen is elongated and muscular, the front pair of appendages end in claws, and the next two pairs of appendages have smaller pincers. All lobsters carry their eggs on the abdominal appendages for seven to 11 months. The larvae emerge in the spring or summer and then float under the surface, where they reach sexual maturity in five or six years. A lobster has a life-span of approximately 20 years. Lobsters hide during the day in burrows and among rocks and emerge at night in search of various invertebrates.
The European lobster is up to 50 cm long and weighs up to 11 kg. It is found along the European coasts, at depths of 35 m during the summer and 65 to 80 m during the winter. Fecundity is up to 32,000 eggs. Reserves of this species have been depleted as a result of commercial fishing.
The American lobster, which is up to 60 cm long and weighs up to 15 kg, is found at depths to 100 m along the coast of North America from Labrador to Virginia. Fecundity is up to 80,000 eggs. Nets are used to catch the American lobster, and the annual catch is approximately 30,000 tons.
The Norway lobster reaches a length of 32 cm and a weight of 7 kg. It is distributed from the Lofoten Islands and Iceland to the coast of Morocco and the Adriatic Sea. It is found at depths of 10 to 800 m. Fecundity is up to 6,000 eggs. The lobster is caught by trawls, with the annual catch totaling up to 20,000 tons.
Lobsters are eaten fresh, or they may be frozen or canned.
N. A. ZARENKOV
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