Deep Sea Shellfish
Shellfish is a gastronomic and fisheries term for those marine invertebrate natural worlds that are used as food: different species of molluscs, crustaceans, and echinoderms. Even though the word is primarily used as a term for marine species, freshwater edible invertebrates (such as crayfish and river mussels etc) are also occasionally grouped with the aquatic genus under the umbrella concept of "shellfish". In its broadest definition, it also consists of such things as edible land snails’ escargot, edible land crabs, etc.
Almost all shellfish have a hard external or exoskeleton, known s a shell, hence the first part of the expression. The second word section "fish", is here used in the antiquated intellect, to mean an animal that lives its whole life in water. However, these invertebrate animals are not "fish" in the new sense of the word, and therefore the term finfish or fin fish is sometimes used to distinguish ordinary fish from shellfish.
Crabs are decapods crustaceans of the infraorder Brachyura, which normally have a very short projecting "tail"or where the condensed abdomen is wholly hidden under the thorax. They are generally sheltered with a thick exoskeleton, and armed with a single pair of chelae (claws). 6,793 species are known. Crabs are found in all of the world's oceans. Additionally, there are also many freshwater and terrestrial crabs, particularly in tropical regions. Crabs vary in size from the pea crab, only a few millimetres wide, to the Japanese spider crab, with a leg span of up to 4 m.
Crabs are decapods—ten-legged omnivores—but the front pair of legs are specialized with enlarged claws, so they are often described as eight-legged. Some species feed primarily on algae, while others take any brand of food, including mollusks, worms, other crustaceans, fungi, bacteria, and detritus, depending on accessibility and on the variety of crab.
Crayfish, crawfish, or crawdads are freshwater crustaceans similar to tiny lobsters, to which they are most likely closely interrelated. They respire throughout noiseless gills and are start in bodies of water that do not freeze up to the bottom; they are also mostly create in brooks and streams where there is bright water running, and which have shelter against predators. Most crayfish cannot stomach grimy water, although some species such as the invasive Procambarus clarkii are hardier. Some crayfish have been found living as much as 3 m (10 feet) underground.The body of a decapods crustacean, such as a crab, lobster, 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. On average, crayfish grow to 7.5 centimeters in length, but some grow larger.
Lobsters are invertebrates and are originated all over the world. They have a hard defensive exoskeleton. Like most arthropods, lobsters must molt by regulate to grow, departure them susceptible during this time. During the molting process, several species may experience a change in color.
Lobsters live on rocky, sandy, or muddy bottoms from the shoreline to beyond the edge of the continental shelf. They normally live alone in crevices or in burrows under rocks.
Lobsters classically eat live food, consisting of fish, mollusks, other crustaceans, worms, and some plant life. Sporadically, they will scavenge if necessary, and may resort to cannibalism in captivity; however, this has not been observed in the wild. Lobster skin in the stomachs of lobsters has been found before, although this is because lobsters will eat their shack skin after molting. Lobsters grow all through their lives and it is not abnormal for a lobster to live for more than 100 years.
Prawn is also called as Shrimp. Prawns are swimming, decapods crustaceans classified in the infraorder Caridea, found widely around the world in both fresh and salt water. Adult Prawns are filter feeding benthic animals breathing close to the sea bottom. They can live in schools and can swim rapidly backwards. Shrimp are an important food source for larger animals from fish to whales. They have a high struggle to toxins in dirty areas, and may supply to high toxin levels in their predators. Together with prawns, shrimp are widely trapped and farmed for human utilization.A Prawn fish farm is an aquaculture business for the cultivation of marine shrimp or prawns for human consumption. Commercial shrimp farming began in the 1970s, and production grew steeply, particularly to match the market hassle of the U.S., Japan and Western Europe. The total global production of farmed shrimp reached more than 1.6 million tonnes in 2003, instead of a value of nearly 9,000 million U.S. dollars. About 75% of farmed shrimp is fashioned in Asia, in fastidious in China and Thailand. The other 25% is produced mainly in Latin America, where Brazil is the largest producer. The largest exporting nation is Thailand.