The Japanese spider crab is a species of marine crab and is the biggest one that lives in the waters around Japan. At around 3.7 meters, it has the largest leg-span of any arthropod. The Japanese name for this species is taka-ashi-gani,, literally translating to “tall legs crab”. It goes through three main larval stages along with a prezoeal stage to grow to its great size.
Cherax parvus is a species of crayfish in the family Parastacidae. It is only known from its type locality – the Upper Tully River catchment in the Cardwell Range of north-eastern Queensland – and is listed as data deficient on the IUCN Red List. It was discovered in a rainforest catchment in a highland of northeastern Queensland during a Queensland Museum expedition to the upper Tully River area in November 1992. It is one of the smallest species in the genus. No species of Cherax has been considered endemic to wet upland or highland areas before it was discovered; most previous records were from elevations less than 400 meters. It also has several morphological features unique to the genus, and does not appear closely related to any extant species, suggesting a long period of geographic isolation.
Parapinnixa affinis, the California Bay pea crab, is a species of pinnotherid crab endemic to Southern California. It is a small crab that lives commensally in the tube of a tube-dwelling worm. It was one of the first marine crustaceans to be included on the IUCN Red List in 1996.
The purple shore crab is a common crab of the family Varunidae that is indigenous to the west coast of United States, Canada, and Mexico. H. nudus was first described in 1847 by Adam White, and in 1851, James Dwight Dana formally classified the species. H. nudus is a small, amphibious crab that is similar physically and behaviorally to Pachygrapsus crassipes and Hemigrapsus oregonensis. The purple shore crab is generally a dark purple color with olive green, red, and white spots. Mating season for H. nudus begins in mid-winter and larval crabs undergo 5 zoeal stages and a juvenile stage. Adult crabs mainly feed on algae but will occasionally scavenge other animals. H. nudus prefers inter-tidal and sub-tidal zones, and it can oftentimes be found sheltering under rocks or other debris. H. nudus demonstrates complex compensatory mechanisms to counteract fluctuating salinity and water oxygen concentrations, permitting it to live in a variety of different environments.
Crustaceans may pass through a number of larval and immature stages between hatching from their eggs and reaching their adult form. Each of the stages is separated by a moult, in which the hard exoskeleton is shed to allow the animal to grow. The larvae of crustaceans often bear little resemblance to the adult, and there are still cases where it is not known what larvae will grow into what adults. This is especially true of crustaceans which live as benthic adults, more-so than where the larvae are planktonic, and thereby easily caught.
Loxorhynchus grandis, commonly known as the sheep crab or spider crab, is a species of crab in the family Epialtidae. It is the largest crab found on the California coast. The species was first described to science by William Stimpson in 1857. The type specimen was collected on the coast of California, near San Francisco. Fossils from the late Miocene epoch indicate that this species is at least 11.63 to 5.333 million years old.
Oregonia bifurca, commonly known as the split-nose crab or the split-nose decorator crab, is a species of crabs belonging to the family Oregoniidae. It is a rare deep-water species that inhabits the tops of seamounts and guyots in the northeastern Pacific Ocean; from the Aleutian Islands, the Bering Sea, the Hawaiian–Emperor seamount chain, to the waters off British Columbia. It is closely related to the more common shallow-water species Oregonia gracilis, the graceful decorator crab.
Dorippe frascone, the urchin crab or carrier crab, is a small species of crab in the family Dorippidae that was first described scientifically by J.F.W. Herbst, in 1785. It is found in the Red Sea and parts of the western and eastern Indian Ocean. It often has a symbiotic relationship with a long-spined sea urchin and carries one around on its carapace.
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.
Phalangipus longipes is a species of crabs in the family Epialtidae.
Armases cinereum, also known as the squareback marsh crab or wharf crab, is a species of crab in the family Sesarmidae. The wharf crab is a small crab that is dark brown to muddy in color, which allows it to blend in with its usual surroundings. It is found on the Atlantic southeastern coast, down into the Gulf of Mexico. It is an omnivore and is prevalent in marshy coastal environments along the Southwestern Atlantic.
Pseudohelice subquadrata is a species of crab in the family Varunidae. It is found from the eastern Indian Ocean to the western Pacific Ocean, north to Japan, south to Eastern Australia, east to French Polynesia, west to Indonesia and Thailand. It lives near mangroves, burrowing in firm soils, firm muddy sand or loose stones. Burrows are towards or above the high tide line on shores of estuaries and near river mouths of bays, and can have offshoots horizontal beneath the surface as long as three metres.
Helopgrapsus haswellianus or Haswell’s shore crab, is the sole species of crab in the genus Helograpsus. It lives in river mouths and bays on the eastern coast of Australia. The carapace is strongly convex with one distinct notch behind the eye. Adult males have larger claws than adult females. The carapace is olive, dark slate grey or reddish. Claws of adult males are orange-yellow. Carapace size is up to 30 mm wide. The orange color is stronger when these crabs live in habitat with lower pollution levels.
Paragrapsus laevis is a species of crab found in south eastern Australia, from southern Queensland to around the South Australian border, including Tasmania.
Davusia glabra, commonly called the shiny bait crab, Sowrie crab or Sourie crab is the sole species of crab in the genus Davusia. It lives around the low tide area on rocky ocean shores on the eastern coast of Australia, in crevices and rock pools and on rock platforms. Its distribution is stated differently in different sources; some have described the crab's habitat as from Queensland to as far south as the NSW-Victorian border, while others have stated it can be found as far south as Wilson's Promontory. Its carapace is grey to fawn-colored with very small green spots, resulting in Davusia glabra having a greenish appearance. The width of the carapace is around 30-40 mm across and is smooth without hair, slightly wider than long, with 3 distinct spines at each edge.
Macrophthalmus setosus is a species of sentinel crab found on the east coast of Australia, from around Queensland to Sydney. Macrophthalmus setosus is found low down on muddy river and creek banks and in exposed sea grass areas in tidal zones, at times near mangroves. Males have a tooth on the upper claw (dactyl). The carapace is around 40 mm wide, and rectangular, greater than 1.7 times wide than long. Eye stalks are long and thin.
Macrophthalmus crassipes is a species of sentinel crab in the family Macrophthalmidae, found around China, Thailand, Malaysia, Australia, and the Caroline Islands. In Australia it is found from north Western Australia through to New South Wales. Common names include the seagrass sentinel crab and the orange spined sentinel crab. On adult males there is a substantial tooth on the lower claw and a much smaller tooth on the upper claw, and noticeable orange spines on the “wrist” (carpus) of the clawed leg and on the palm of the clawed leg. The carapace is covered in small granules, and is up to around 37 mm (1.5 in) across. It is a burrowing crab, and lives in open tidal flats, muddy or with sandy mud, low on tidal creek banks, and adjacent mangroves.
Tubuca coarctata is a species of fiddler crab found in the western Pacific ocean, including Japan, Taiwan, the Philippines, Indonesia, New Guinea and Australia. The common name of these crabs is either the compressed fiddler crab, or the orange-clawed fiddler crab,. They are found on tidal mud flats adjacent mangroves and muddy tidal creek and river banks.
Portunus armatus is a species of crustacean, a swimming crab in the family Portunidae found in Australia and eastwards to New Caledonia. Common names include blue swimmer crabs, Blue manna, Blueys, and Jennies. The species was originally considered as a geographic variation of Portunus pelagicus, however in 2010 the Portunus pelagicus species was reviewed using DNA, as well as physical characteristics including measurements and four species recognised: Portunus pelagicus, Portunus armatus, Portunus reticulatis and Portunus segnis. The range of Portunus armatus overlaps with Portunus pelagicus in the Northern Territory of Australia.
Tasmanoplax latifrons, commonly known as the southern sentinel crab, is a species of crab found on the south-east coast of Australia, from Tasmania to southern NSW, as far north as the Hunter river. It inhabits tidal mudflats with seagrass, and forms burrows. It is the only species in the genus Tasmanoplax.
