Shrimps are decapod crustaceans that have prolonged bodies with a swimming style of movement. This is common mostly in Dendrobranchiata and Caridea.
Under a wider definition, shrimp are sometimes regarded as prawn, covering stalk-eyed swimming crustaceans with long narrow muscular tails (abdomens), long antennae, and thin legs.
They swim forward by paddling with swimmers at the bottom of their abdomen, although their escape response is usually repetitive motions, with the tail propelling them backwards very quickly.
In the food chain, shrimps Play a very significant part, and they are a good source of food for humans and other larger animals ranging from fish to whales.
The muscular tails of many shrimp are human edible and are often caught and bred for human consumption.
Commercial shrimp species sustain an industry worth $50 billion annually, and as of 2010, the total commercial shrimp production was nearly 7 million tons.
The species of shrimps vary in sizes, ranging from 0.79inches to 9.8inches.
Classification
- Phylum: Arthropoda
- Subphylum: Crustacea
- Class: Malacostraca
- Subclass: Eumalacostraca
- Superorder: Eucarida
- Order: Decapoda
- Suborder: Natantia
- Superfamily: Penaeoidea
- Family: Penaeidae
- Genus: Penaeus
- Scientific name: Caridea
Description
A shrimp’s body has to division namely: head and thorax(chest), that are coalesced together to form what we call Cephalothorax as well as a long abdomen.
The Cephalothorax is protected by a shell which is thicker and harder than any other shell covering other parts of the shrimp. It is through the carapace which encircles the gills that water is pumped by the movements of the mouth parts.
The whiskers, rostrum, legs, and eyes also emanate from the carapace. The rostrum which is beak-like in shape, is situated at the front of the shrimp’s head, and can serve as a shield or a weapon for attack to the shrimp.
There are six segments in the muscular abdomen, and the shell found there is thinner than that of the carapace. Each of the six segments has separate shell that overlap each other.
Each of the first five segments has a pair of appendages on the underside, that have a paddle-like shape, used for swimming in the forward direction. The appendages are otherwise called swimmerets or pleopods.
The sixth segment ends in the telson with a double pair of appendages called Uropods, on both wings.
Habitat
Shrimps are very common, they mostly found near the seafloor of most estuaries, lakes, seas coast and rivers.
The species of shrimps are vast, and each specie adapts to a particular habitat. At a depth, measuring 16,000 ft are found Marine species, and they come from the tropics of the polar regions.
Of the numerous species of shrimps which are aquatic in nature, only the two species of Merguia are semi-terrestrial and they live mostly on land in mangrove.
Lysmata amboinensis which is a specie of shrimp, live in partially shallow waters and rest at the bottom of the sea with the use of their walking legs.
Behavior
Different species of shrimps behave and look differently. Let us take for an example, the core group of Caridea shrimp, we see that within this group, pederson’s shrimp, which is minute and delicate in nature, behaves differently from the large commercial pink shrimp.
What characterizes the Caridea family of shrimps is their claws which are asymmetrical in arrangement.
Worthy of note is the fact that the primary source of noise in the ocean is the snapping shrimp which appear in colonies and because of this noise created by the colonies, they tend to obstruct the underwater and sonar communication.
Shrimps are mostly omnivores though some have a special mode of feeding. Some shrimps are regarded as filter feeders and they make use of their bristly or setose as a sieve.
Other species of shrimps like the cleaner shrimp feed on necrotic tissue of reef fish, as well as parasites of the reef fish. Some species of shrimp also feed on other smaller shrimps especially when their source of food is not available.
Mating
The female shrimps which belong to caridina ensifera specie are known to store up sperm from several male shrimps, as such they can produce offspring with different patternities.
Species
1.Decapods
Decapods are traditionally divided into two Suborder namely: Reptantia or walkers, and Natantia or swimmers. Shrimps fall under Natantia while crabs and lobsters belong to the Reptantia or walkers.
It was a common belief that all shrimps were Decapods or paraphyletic.
2 Non-decapods
Most shrimps are widely referred to as non-decapod crustaceans. Included also in this species are various shrimps like; fairy shrimp, brine shrimp, tadpole shrimp, and clam shrimp which belong to the Branchiopods; and opposum shrimp lophogastridan shrimp and skeleton shrimp which belong to Malacostraca.
Most of these shrimps differ greatly from the commercial decapod shrimp which are consumed as seafood.
Human Uses
Most shrimps are widely used for commercial purposes, as they are sold at the market and eaten as seafood. They are a great source of protein and cholesterol. At homes, shrimps are used as ornaments, and in aquaria to add beauty to the home.
