The Bering Sea is a marginal sea of the Northern Pacific Ocean. It forms, along with the Bering Strait, the divide between the two largest landmasses on Earth: Eurasia and the Americas. It comprises a deep water basin, which then rises through a narrow slope into the shallower water above the continental shelves. The Bering Sea is named after Vitus Bering, a Danish-born Russian navigator, who, in 1728, was the first European to systematically explore it, sailing from the Pacific Ocean northward to the Arctic Ocean.
Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting tail-like abdomen, usually hidden entirely under the thorax. They live in all the world's oceans, in freshwater, and on land, are generally covered with a thick exoskeleton, and have a single pair of pincers on each arm. They first appeared during the Jurassic period, around 200 million years ago.
Hermit crabs are anomuran decapod crustaceans of the superfamily Paguroidea that have adapted to occupy empty scavenged mollusc shells to protect their fragile exoskeletons. There are over 800 species of hermit crab, most of which possess an asymmetric abdomen concealed by a snug-fitting shell. Hermit crabs' soft (non-calcified) abdominal exoskeleton means they must occupy shelter produced by other organisms or risk being defenseless.
King crabs are decapod crustaceans in the family Lithodidae that are chiefly found in deep waters and are adapted to cold environments. They are composed of two subfamilies: Lithodinae, which tend to inhabit deep waters, are globally distributed, and comprise the majority of the family's species diversity; and Hapalogastrinae, which are endemic to the North Pacific and inhabit exclusively shallow waters. King crabs are not true crabs and are generally thought to be derived from hermit crab ancestors within the Paguridae, which may explain the asymmetry still found in the adult forms. This ancestry is supported by several anatomical peculiarities which are present only in king crabs and hermit crabs. Although some doubt still exists about this hypothesis, king crabs are the most widely quoted example of carcinisation among the Decapoda. Several species of king crabs, especially in Alaskan and southern South American waters, are targeted by commercial fisheries and have been subject to overfishing.
The Parnaíba River is a river in Brazil, which forms the border between the states of Maranhão and Piauí. Its main course is 1,400 km (870 mi) long and the Parnaíba River Basin covers 330,000 km2 (130,000 sq mi). The Parnaíba River rises in the Chapada das Mangabeiras range, and flows northeastward to empty into the Atlantic Ocean, being the longest river entirely located within Brazil's Northeast Region. The middle and upper regions of this river are separated by the Portuguese: Boa Esperança Hydroelectric Power Plant dam, but is otherwise navigable.
Orithyia sinica, sometimes called tiger crab or the tiger face crab, is a "singularly unusual" species of crab, whose characteristics warrant its separation into a separate genus, family and even superfamily, having previously been included in the Dorippoidea or Leucosioidea. Its larvae, for instance, are unlike those of any other crab.
Several species of crabs share the name pebble crab:
Leucosiidae is a family of crabs containing three subfamilies and a number of genera incertae sedis:
Around 65 species of crab occur in the waters of the British Isles. All are marine, with the exception of the introduced Chinese mitten crab, Eriocheir sinensis, which occurs in fresh and brackish water. They range in size from the deep-water species Paromola cuvieri, which can reach a claw span of 1.2 metres, to the pea crab, which is only 4 mm (0.16 in) wide and lives inside mussel shells.
Ebalia tumefacta, sometimes called Bryer's nut crab, is a species of crab in the family Leucosiidae.
The parona leatherjacket is a species of carangid found along the Atlantic coast of South America from southern Brazil to southern Argentina and the Falkland Islands. This species grows to a length of 60 centimetres (24 in) TL and is of minor importance to local commercial fisheries. This species is the only known member of its genus.
Myra fugax is a species of crabs in the family Leucosiidae.
Coleusia is a genus of Indo-Pacific pebble crabs of the family Leucosiidae. The six species currently recognised were formerly classed as members of the genus Leucosia but were separated into Coleusia in 2006 based on the fusing of segments 3-5 on the abdomens of the males and the three times axial coiling of the shaft of the first pleopod which bears a tufted lobe on its distal portion and has an elongated apical process.
Ixa monodi, the Red Sea pebble crab is a species of pebble crab from the family Leucosiidae which prefers to burrow in sandy, shallow coastal waters. It was first described from the eastern Mediterranean where it is an invasive species having colonised the coasts of the Levantine Sea from the Red Sea by Lessepsian migration from the Red Sea via the Suez Canal.
Persephona mediterranea, the mottled purse crab, is a species of true crab in the family Leucosiidae. It is found in the western Atlantic Ocean.
Persephona is a genus of true crabs in the family Leucosiidae. There are about 5 described species in Persephona.
Randallia ornata, known generally as the globose sand crab or purple globe crab, is a species of true crab in the family Leucosiidae. It is found in the East Pacific.
Randallia is a genus of true crabs in the family Leucosiidae. There are about 17 described species in Randallia.
Dardanus deformis is a species of nocturnal hermit crab that is found in the Indo-Pacific. Its common name is pale anemone hermit. The species is known to transfer sea anemones from one shell to another when it moves to a different shell. It can be kept in an aquarium.
Coleusia janani is a newly discovered species of pebble crabs found off the coast of Qatar in 2017. Its shell is of bright orange and lite grey color with small white centres and lined by thin red outer rings.
