where are they found?
Most shrimp species are marine, although about a quarter of the described species are found in fresh water.
Shrimp
Most shrimp species are marine, although about a quarter of the described species are found in fresh water. 
crustacea and hexapoda have what features in common It is now well accepted that the crustacean group is paraphyletic, and comprises all animals in the clade Pancrustacea other than hexapods. what is the first group that you are talking about? It forms a large, diverse arthropod taxon which includes such animals as crabs, lobsters, crayfish, shrimps, prawns, krill, woodlice, and barnacles. can you describe their body? It is composed of segments, which are grouped into three regions: the "cephalon" or head, the "pereon" or thorax, and the "pleon" or abdomen. and where do they generally live? Majority live in either marine or freshwater environments. have their fossils been found? Yes, they have a rich and extensive fossil record. can you name any organism of this taxon whose fossil has been discovered? Yes, "Canadaspis" and "Perspicaris". how is the former classified? It is currently thought to be a member of the group Hymenocarina. which members of the original taxon that we were talking about are consumed by humans? Crabs, lobsters, shrimp, crawfish, and prawns. what is the third one? They are decapod crustaceans with elongated bodies.
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Shrimp [SEP] Habitat
Shrimp are widespread, and can be found near the seafloor of most coasts and estuaries, as well as in rivers and lakes. There are numerous species, and usually there is a species adapted to any particular habitat. Most shrimp species are marine, although about a quarter of the described species are found in fresh water. Marine species are found at depths of up to , and from the tropics to the polar regions. Although shrimp are almost entirely fully aquatic, the two species of "Merguia" are semi-terrestrial and spend a significant part of their life on land in mangrove.