Shrimp are marine crustaceans that are found on the bottom of the water in nearly every environment around the world. Shrimps
are generally tiny in size, with some species of shrimp being so small that many animals cannot see them. There are more than
2,000 different species of shrimp worldwide, all of which are invertebrates which means that shrimp do not have a backbone.
Instead, shrimp have a hard exoskeleton(the shell of the shrimp)which is often transparent and colourless making shrimp difficult
to see in the water.
Woodlouse is not an insect but a crustacean, that has 14 parts to its body, which gives the woodlouse the flexibility to
be able to curl into a ball to protect itself from danger. This means that only the hard outer shell of the woodlouse is exposed.
The woodlouse is found in dark, damp places in forests and jungles throughout the world. The woodlouse feeds on decaying leaf
and plant matter on the forest floor, meaning that the woodlouse plays a vital role in the natural carbon dioxide cycle.
Prawns are crustaceans similar in appearance to shrimps, but they can be distinguished by the gill structure which is branching
in prawns and not in shrimp. The prawn is also related to the crab and the lobster.
Prawns are found in calmer waters were the prawns can nest in the water plants to lay their eggs. Like the shrimp. the prawn
does tend to prefer the warmer waters in the tropics but some species of prawn are found in the Northern Hemisphere.
Lobster is a large crustacean and like the crab is similar to shrimp and prawns. The lobster is one of the largest types of
of crustacean with some lobster species known to get to weigh over 20 kg.
Lobsters live on rocky, sandy, or muddy bottoms close to the shoreline to beyond the edge of the continental shelf as the lobster
prefers the shallower ocean water. The lobster is generally found to live by itself, where the lobster hides in crevices and
in burrows under rocks.
King Crabs are known for theur sheer size but only a couple of species get really big. King crabs are mainly found in the
Southern Hemisphere where the waters are warmer but the Alaskan king crab is the obvious exception to this as the water there
are near freezing.
Red king crabs can have a leg span of up to 1.8m, blue king crabs often weigh over 8kg!King crabs hunt small fish and plankton
in the oceans and are often found close to coral reefs or rocky areas where there are plenty of places for the king crab to hide.
Crab is a type of crustacean similar to prawns, Shrimps and lobster. There are more than 6,700 known species of crab found
in waters worldwide and these many crab species are split into around 93 different crab groups.
Most crab species are found in the shallower ocean waters where the crabs tend to inhabit rocky pools and coral reefs. There
are however, a number of species of freshwater crab that inhabit the waters in rivers and lakes and some species of tropical
crab have been known to spend a great deal of time on land.
Barnacle is a hardy animal that is found in or very closely to sea water. Although it is frequently confused for a mollusc
because of its hard outer shell, it is actually a crustacean, closely related to crabs and lobsters.
Barnacles are most often seen as roughly circular sessile invertebrates(which means that they cannot move in their own), and
are permanenetly attached to the substrate they live on. In their juvenile form they are free-floating, but eventually they
eventually they attach themselves to any nearby rock shell, or other object and stay there for the rest of their lives. Their
shells are composed of calcite.
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