Search results
Results from the WOW.Com Content Network
The decapod (crustaceans, 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 (). [1] [2] Each segment may possess one pair of appendages, although in various groups these may be reduced or missing.
Crabs vary in size from the pea crab, a few millimeters wide, to the Japanese spider crab, with a leg span up to 4 m (13 ft). [6] Several other groups of crustaceans with similar appearances – such as king crabs and porcelain crabs – are not true crabs, but have evolved features similar to true crabs through a process known as carcinisation .
A shed carapace of a lady crab, part of the hard exoskeleton Body structure of a typical crustacean – krill. The body of a crustacean is composed of segments, which are grouped into three regions: the cephalon or head, [5] the pereon or thorax, [6] and the pleon or abdomen. [7]
Diagram of a prawn, with the carapace highlighted in red. A carapace is a dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron.
Diagram highlighting the telson of the prawn Litopenaeus setiferus Telson (arrow no. 3) of the horseshoe crab Carcinoscorpius rotundicauda. The telson (from Ancient Greek τέλσον 'headlands, limit') is the hindmost division of the body of an arthropod.
The phylogeny of king crabs as hermit crabs who underwent secondary calcification and left their shell has been suspected since the late 1800s. [4] They are believed to have originated during the Early Miocene in shallow North Pacific waters, where most king crab genera – including all Hapalogastrinae – are distributed and where they exhibit a high amount of morphological diversity.
The aerial shot enables viewers to see the full body of the crab, including its pinchers and legs. It's estimated that the beast measures 50 feet long. Quinton Winter, who runs a website devoted ...
A hermit crab emerges from its shell, Coenobita perlatus Outside its shell, the soft, curved abdomen of hermit crabs, such as Pagurus bernhardus, is vulnerable. Hermit crab species range in size and shape, from species only a few millimeters long to Coenobita brevimanus (Indos Crab), which can approach the size of a coconut and live 12–70 years.