What is meant by decapod?
What is meant by decapod?
Decapod, (order Decapoda), any of more than 8,000 species of crustaceans (phylum Arthropoda) that include shrimp, lobsters, crayfish, hermit crabs, and crabs.
What is the anatomy of a shrimp?
The body of the shrimp is divided into two main parts: the head and thorax which are fused together to form the cephalothorax, and a long narrow abdomen. The shell which protects the cephalothorax is harder and thicker than the shell elsewhere on the shrimp and is called the carapace.
Does a decapod have 10 legs?
Decapods have ten legs. The last five pair of appendages on their thorax are walking legs. In some species, the first pair of walking legs have large pinchers or chelipeds. Decapods have three pairs of appendages, or maxillipeds, on their heads that make up their mouthparts.
Are pleopods legs?
Pleopods (also called swimmerets) are primarily swimming legs, and are also used for brooding the eggs (except in prawns), catching food (then swept to the mouth), and can sometimes bear their own gills.
Why are squids called Decapods?
Cephalopods. The Phylum Mollusca is one of the largest and most diverse of the animal groups. The name Mollusca comes from the Latin word mollis (meaning soft). The word mollusc was first used by the French zoologist Cuvier in the late 1700’s to describe squids and cuttlefishes, members of the Class Cephalopoda.
What is the poop vein in shrimp?
black vein
The black vein that runs along the back of the shrimp is an intestinal tract of unappetizing grit. While shrimp can be cooked and eaten with or without the vein, most people prefer it removed for the taste and presentation. And deveining shrimp is very easy to do.
Why are shrimp segmented?
Presumably, it provides stability while swimming. Shrimp have 5 pairs of jointed legs on the thorax, 3 pair are used for walking and 2 pair have claws and are used for feeding (some species have 2 for walking and 3 for feeding). Shrimp have two pairs of segmented sensory antennae and compound eyes.
What is the other name for pleopods?
member extremity appendage isopod shrimp lobster swimmeret pleopod.
Why do squids have 3 hearts?
The branchial hearts pump blood to the gills, where oxygen is taken up. Blood then flows to the systemic heart, where it is pumped to the rest of the body. The systemic heart is made of three chambers: a lower ventricle and two upper auricles.
What is the function of the pen in a squid?
The pen or gladius of the squid is an internalized shell and serves as a site of attachment for important muscle groups and as a protective barrier for the visceral organs.
How many appendages does a decapod have?
Decapod anatomy. The decapod crustacean, such as a crab, lobster, shrimp or prawn, is made up of 20 body segments grouped into two main body parts, the cephalothorax and the pleon (abdomen). Each segment may possess one pair of appendages, although in various groups these may be reduced or missing.
How is the abdomen of a decapod folded?
In crabs and some other carcinised decapods, the abdomen is folded under the cephalothorax. The anatomy of krill, using Euphausia superba as a model. The pleopods of Euphausia superba. Crab moult with carapace lifted, exposing gills.
Where are the legs located in a Decapoda?
As the name Decapoda (from the Greek δέκα, deca-, “ten”, and πούς / ποδός, -pod, “foot”) implies, ten of these appendages are considered legs. They are the pereiopods, found on the last five thoracic segments. In many decapods, one pair of these “legs” has enlarged pincers, called chelae, with the legs being called chelipeds.
What kind of eyes does a decapod have?
The head also bears the (usually stalked) compound eyes. The distal portion of a mandible or maxilla which has a sensory function is known as a palp . Maxillipeds are appendages modified to function as mouthparts. Particularly in the less advanced decapods, these can be very similar to the pereiopods.