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.
Mussel is the common name used for members of several families of bivalve molluscs, from saltwater and freshwater habitats. These groups have in common a shell whose outline is elongated and asymmetrical compared with other edible clams, which are often more or less rounded or oval.
Pinnotheres is a genus of crabs, including the pea crab. Many species formerly in Pinnotheres have been placed in new genera, such as Zaops ostreus, the oyster crab and Nepinnotheres novaezelandiae, the New Zealand pea crab. The species currently recognised in the genus Pinnotheres are:
Perna canaliculus, the New Zealand green-lipped mussel, also known as the New Zealand mussel, the greenshell mussel, kuku, and kutai, is a bivalve mollusc in the family Mytilidae. P. canaliculus has economic importance as a cultivated species in New Zealand.
The Smooth Shore Crab is a marine large-eyed crab of the family Grapsidae, found in New Zealand and the Juan Fernández Islands of Chile.
Pinnotheridae is a family of tiny soft-bodied crabs that live commensally in the mantles of certain bivalve molluscs and the occasional large gastropod mollusc species in genera such as Strombus and Haliotis. Tunicotheres moseri is commensal with a tunicate. The earliest fossils attributable to the Pinnotheridae date from the Danian.
The pea crab, Pinnotheres pisum, is a small crab in the family Pinnotheridae that lives as a parasite in oysters, clams, mussels, and other species of bivalves.
The oyster crab is a small, whitish or translucent crab in the family Pinnotheridae.
Pinnixa faba, known as the pea crab, mantle pea crab or large pea crab, is a pea crab which lives harmlessly within a large edible clam. This species is a symbiont of Tresus capax and Tresus nuttallii in its mature stage.
Pinnotheres atrinicola is a small crab that lives symbiotically in the horse mussel Atrina zelandica around New Zealand. This species was recognised as being distinct from Pinnotheres novaezelandiae in 1983.
Stichaster australis, the reef starfish, is a species of starfish found in the shallow waters of the rocky intertidal of New Zealand. Typically, the animal is endemic to the west coast shores of the North and South Islands, where wave action is increased. They do not usually inhabit ecosystems that have reduced wave action and calm conditions as they prefer a higher-energy environment. These marine invertebrates range in color from pink to purple, but can also be orange. They typically have eleven arms, but sometimes they may have either ten or twelve. As full-grown adults, they are 8 to 10 cm in diameter.
Atrina zelandica, one of several species known as the horse mussel, is a large species of saltwater clam. It is found around New Zealand.
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.
Petrolisthes novaezelandiae, known as the red half crab or red false crab, is a species of porcelain crab native to New Zealand.
Andrea Casandra Alfaro is an American-New Zealand aquaculture and marine ecology academic. She is currently a full professor at the Auckland University of Technology.
Tunicotheres is a monotypic genus of crabs in the family Pinnotheridae, and Tunicotheres moseri is the only species in the genus. This crab lives commensally in the atrial chamber of a small ascidian. It is found in the tropical western Atlantic Ocean, the Caribbean Sea and the Gulf of Mexico.
Calyptraeotheres garthi is a species of pea crab in the family Pinnotheridae. It is found in the southwestern Atlantic Ocean and is a parasitic castrator of the slipper limpet Crepidula cachimilla.
Scott Point is a point at the northern end of Ninety Mile Beach in the Northland Region, New Zealand. It is the site of a major intertidal green-lipped mussel population.
Kura Paul-Burke is a New Zealand Māori marine scientist, and is the first woman Māori professor of marine science at the University of Waikato. Her research focuses on mātauranga Māori and aquaculture.
