Atlantic ghost crab | |
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Adult O. quadrata by a burrow entrance | |
Juvenile O. quadrata | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Malacostraca |
Order: | Decapoda |
Suborder: | Pleocyemata |
Infraorder: | Brachyura |
Family: | Ocypodidae |
Genus: | Ocypode |
Species: | O. quadrata |
Binomial name | |
Ocypode quadrata | |
Synonyms | |
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The Atlantic ghost crab, Ocypode quadrata, is a species of ghost crab. It is a common species along the Atlantic coast of the United States, where it is the only species of ghost crab; [2] its range of distribution extends from its northernmost reach on beaches in Westport, Massachusetts, south along the coasts of the tropical Western Atlantic Ocean to the beach of Barra do Chui, in Rio Grande do Sul in southern Brazil. [3]
Adults are grayish or the color of straw, and around 5 cm (2.0 in) wide at maturity. [4] They must return to water periodically to moisten their gills, and when larvae must be released into the sea, but are otherwise terrestrial. [4] Their stalked compound eyes can swivel to give them 360° vision. [2] Young crabs are cryptically colored to blend in with their sandy habitats. [2]
Atlantic ghost crabs are found from Santa Catarina north to Massachusetts, USA. They have been recorded in Block Island, Rhode Island, Nantucket, Massachusetts, Martha's Vineyard, Massachusetts, Delaware beaches, northern Virginia beaches, the Outer Banks of North Carolina to Santa Catarina, Brazil, on Fernando de Noronha, and Bermuda. Its planktonic larvae have been documented in Woods Hole, Massachusetts, although the adults have not been recorded at this location. [4]
Fossil specimens of O. quadrata have been found in rocks dating from the Pleistocene. [5]
The Atlantic ghost crab lives in burrows in sand above the strandline. [2] Older individuals dig their burrows farther from the sea, some starting as much as 400 m (1,300 ft) inland. [4] Burrows can be up to 1.3 m (4 ft 3 in) deep, and can be closed off with sand during hot periods. [4]
This crab can produce a variety of sounds by striking the ground with the claw, by stridulation with the legs, and an incompletely explained "bubbling sound". [6] Males compete in a heavily ritualised manner which prevents the need for physical contact. [6] [ further explanation needed ]
Ghost crabs are arguably the fastest terrestrial invertebrates, capable of running at more than a meter per second. [7]
O. quadrata is more active at night than in the day, and is an omnivore, [2] eating clams (such as conquina clams and Donax spp.), [8] mole crabs (including Emerita talpoida ), [9] [8] insects, plant material, detritus, and even other crabs. [6] They also feed on the eggs and hatchlings of sea turtles, such as the loggerhead sea turtle. [9] [8]
Sandy beaches, a habitat frequented by ghost crabs, have had a decrease in the abundance of ghost crabs due to human behavior. [10] Ghost crabs are negatively impacted by human and vehicle trampling, which results in direct crushing of crabs, as well as indirect damage such as compression of sediment which reduces habitat suitability, interference with reproductive behaviors, reduction in food supply, and light pollution. [11] Consequently, they may be less common on beaches frequented by people.
A 2023 study using the well known mirror test found that these crabs seem to be capable of recognizing themselves in a mirror. The study's author concluded that the data indicate that the crabs have "a rudimentary form of self-awareness". [12]
Ghost crabs are semiterrestrial crabs of the subfamily Ocypodinae. They are common shore crabs in tropical and subtropical regions throughout the world, inhabiting deep burrows in the intertidal zone. They are generalist scavengers and predators of small animals. The name "ghost crab" derives from their nocturnality and their generally pale coloration. They are also sometimes called sand crabs, though the name refers to various other crabs that do not belong to the subfamily.
Emerita is a small genus of decapod crustaceans, known as mole crabs, sand fiddlers, or sand crabs. These small animals burrow in the sand in the swash zone and use their antennae for filter feeding.
Ocypode is a genus of ghost crabs found in the sandy shores of tropical and subtropical regions throughout the world. They have a box-like body, thick and elongated eyestalks, and one claw is larger than the other in both males and females. They inhabit deep burrows in the intertidal zone. They are primarily nocturnal, and are generalist scavengers and predators of small animals. The genus contains 21 species.
Cahuita National Park is a terrestrial and marine national park in the Caribbean La Amistad Conservation Area of Costa Rica located on the southern Caribbean coast in Limón Province, connected to the town of Cahuita. It protects beaches and lowlands and attracts tourists and other visitors who are able to snorkel in the protected marine area which contains the coralline reefs, as well as being a nesting ground for sea turtles. It covers a land area of 2,732 acres (1,106 ha), and a marine area of 55,200 acres (22,300 ha). February through April typically have the best underwater visibility. This is also one of the nicest and least developed beaches in Costa Rica.
Sand bubbler crabs are crabs of the genera Scopimera and Dotilla in the family Dotillidae. They are small crabs that live on sandy beaches in the tropical Indo-Pacific. They feed by filtering sand through their mouthparts, leaving behind balls of sand that are broken up by the incoming high tide.
The pallid ghost crab, Ocypode pallidula, is a small ghost crab that digs burrows in beaches of the Indo-Pacific region. Its carapace is usually about 1 inch (25 mm) wide.
Minuca pugnax, commonly known as the Atlantic marsh fiddler crab, is a species of fiddler crab that lives on north-western shores of the Atlantic Ocean.
Ocypode ceratophthalmus, the horned ghost crab or horn-eyed ghost crab, is a species of ghost crab. It lives in the Indo-Pacific region ; from the coast of East Africa to the Philippines and from Japan to the Great Barrier Reef. They also occur in the Pacific Islands to as far east as Polynesia and Clipperton Island. As their common name implies, O. ceratophthalmus possess eyestalks extending beyond the eyes into long points, which are longer in adults, and shorter in juveniles. The crabs have a box-shaped body, 6–8 centimetres (2.4–3.1 in) across the carapace, with a darker markings towards the rear in the shape of an H. The outer edges of the eye-sheaths are also sharp and broadly triangular and distinctly pointing sideways in larger individuals. O. ceratophthalmus can run at speeds of up to 2.1 metres per second (6.9 ft/s).
The Anastasia Formation is a geologic formation deposited in Florida during the Late Pleistocene epoch.
Ocypode ryderi, also known as the pink ghost crab, is a species of ghost crab found on the east coast of Africa from the Eastern Cape Region to Kenya.
Mictyris longicarpus, the light-blue soldier crab, is a species of crab that lives on sandy beaches from the Bay of Bengal to Australia; with other members of the genus Mictyris, it is "one of the most loved crabs in Australia". Adults are 25 mm (1 in) across, white, with blue on their backs, and hold their claws vertically. They feed on detritus in the sand, leaving rounded pellets of discarded sand behind them. The males may form into large "armies" which traverse the beach at low tide, before the crabs dig into the sand to wait for the next low tide.
Ocypode gaudichaudii, also known as the painted ghost crab or cart driver crab, is a species of crab found on Pacific beaches from El Salvador to Chile as well as on the Galápagos Islands. The species was first described by Henri Milne-Edwards and Hippolyte Lucas in 1843.
Pinnixa chaetopterana, the tube pea crab, is a small decapod crustacean that lives harmlessly within the tube of the polychaete worm, Chaetopterus variopedatus.
Ocypode cursor, the tufted ghost crab, is a species of ghost crab found on sandy beaches along the coasts of the eastern Atlantic Ocean and eastern Mediterranean Sea.
The gulf ghost crab, Hoplocypode occidentalis, is a species of ghost crabs native to the Pacific coast of the Americas, from the Gulf of California to Colombia. It is the only species in the genus Hoplocypode. Gulf ghost crabs are medium-sized, reaching a maximum overall body diameter of 6 in (15 cm). They are one of only two ghost crab species found in the eastern Pacific. However, gulf ghost crabs can easily be distinguished from painted ghost crabs by the absence of "horns" on their eyes.
Ocypode africana, commonly known as the African ghost crab, is a species of ghost crabs native to the eastern Atlantic coast of western Africa, from Mauritania to Namibia. They are medium-sized ghost crabs reaching carapace width of 3.4 cm (1.3 in). They can vary in coloration from pinkish to dark grey. They are one of only two ghost crab species found in the eastern Atlantic. However, African ghost crabs can easily be distinguished from tufted ghost crabs by the absence of long tufts of hair on the tip of their eyestalks.
Ocypode brevicornis is a species of ghost crab native to the Indian Ocean, from the Gulf of Oman to the Nicobar Islands. They are relatively large ghost crabs with a somewhat trapezoidal body. The carapace reaches a length of 41 mm (1.6 in) and a width of 50 mm (2.0 in). They are a mottled brown to yellow in coloration. Like other ghost crabs, one of their claws is much larger than the other. Their eyestalks are large and elongated, tipped with prolongations at the tip known as styles. They are common inhabitants of open sandy beaches, living in burrows in the intertidal zone.
Ocypode convexa, commonly known as the golden ghost crab, or alternatively the western ghost crab or yellow ghost crab, is a species of ghost crabs endemic to the coast of Western Australia, from Broome to Perth. They are relatively large ghost crabs, with a carapace growing up to 45 mm (1.8 in) long and 52 mm (2.0 in) wide. They are easily recognisable by their golden yellow colouration. Like other ghost crabs they have box-like bodies with unequally sized claws. They also have large eyestalks with the cornea occupying most of the bottom part.
Ocypode fabricii is a species of ghost crabs endemic to the coast of northern and western Australia, from Darwin to Shark Bay. They are medium-sized ghost crabs with a squarish body. The carapace reaches a length of 38 mm (1.5 in) and a width of 40 mm (1.6 in). Like other ghost crabs, one of their claws is much larger than the other. They live in burrows in the intertidal zones of the muddy to sandy beaches of mangrove forests.
Emerita talpoida, known generally as the Atlantic mole crab or Atlantic sand crab, is a species of mole crab in the family Hippidae. It is found in the western Atlantic Ocean and Mexico along the shoreline.