Petrolisthes | |
---|---|
New Zealand half crab, P. elongatus | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Malacostraca |
Order: | Decapoda |
Suborder: | Pleocyemata |
Infraorder: | Anomura |
Family: | Porcellanidae |
Genus: | Petrolisthes Stimpson, 1858 |
Type species | |
Porcellana violacea Guérin, 1829 [1] |
Petrolisthes is a genus of marine porcelain crabs, containing these extant species: [2] [3]
Carcinisation is a form of convergent evolution in which non-crab crustaceans evolve a crab-like body plan. The term was introduced into evolutionary biology by L. A. Borradaile, who described it as "the many attempts of Nature to evolve a crab".
Porcelain crabs are decapod crustaceans in the widespread family Porcellanidae, which superficially resemble true crabs. They have flattened bodies as an adaptation for living in rock crevices. They are delicate, readily losing limbs when attacked, and use their large claws for maintaining territories. They first appeared in the Tithonian age of the Late Jurassic epoch, 145–152 million years ago.
Alpheus is a genus of snapping shrimp of the family Alpheidae. This genus contains in excess of 330 species, making this the most species-rich genus of shrimp. Like other snapping shrimp, the claws of Alpheus are asymmetrical, with one of the claws enlarged for making a popping noise. Some species in the genus enter into symbiotic relationships with gobiid fishes, and others associate with sea anemones.
Palaemonidae is a family of shrimp in the order Decapoda. Many species are carnivores that eat small invertebrates, and can be found in any aquatic habitat except the deep sea. One significant genus is Macrobrachium, which contains commercially fished species. Others inhabit coral reefs, where they associate with certain invertebrates, such as sponges, cnidarians, mollusks, and echinoderms, as cleaner shrimps, parasites, or commensals. They generally feed on detritus, though some are carnivores and hunt tiny animals.
Palaemon is a genus of caridean shrimp in the family Palaemonidae.
Paguristes is a genus of hermit crab in the family Diogenidae. It includes the following species :
Galathea is a genus of squat lobsters in the family Galatheidae. It is one of the largest genera of squat lobsters that in 2008 contained 73 species. Most species of Galathea live in shallow waters.
Pilumnoidea is a superfamily of crabs, whose members were previously included in the Xanthoidea. The three families are unified by the free articulation of all the segments of the male crab's abdomen and by the form of the gonopods. The earliest fossils assigned to this group are of Eocene age.
Lysmata is a genus of shrimp in the infraorder Caridea, the caridean shrimp. The genus belongs to the family Lysmatidae. Lysmata are popular ornamental shrimp in the marine aquarium trade for their bright color patterns, interesting behaviors, and ability to control certain aquarium pests such as sea anemones of the genus Aiptasia. They are known to command high prices on the pet market.
The Galatheoidea are a superfamily of decapod crustaceans comprising the porcelain crabs and some squat lobsters. Squat lobsters within the three families of the superfamily Chirostyloidea are not closely related to the squat lobsters within the Galatheoidea. The fossil record of the superfamily extends back to the Middle Jurassic genus Palaeomunidopsis.
Porcellana is a genus of decapod crustaceans in the widespread family Porcellanidae, the porcelain crabs, which superficially resemble true crabs. The genus Porcellana includes the following species:
Allopetrolisthes spinifrons is a species of porcelain crab. It displays "hypercarcinisation", whereby the resemblance to a true crab is enhanced by sexual dimorphism of the abdomen. It lives along the Pacific coast of Peru and Chile, as a symbiont of a sea anemone.
Allopetrolisthes is a genus of porcelain crabs, comprising three species:
Pilumnus is a genus of crabs, containing the following species:
Polyonyx is a genus of porcelain crabs in the family Porcellanidae. There are at least 42 described species in Polyonyx.
Pachycheles is a genus of porcelain crabs in the family Porcellanidae. There are more than 40 described species in Pachycheles.
Periclimenes, commonly known as glass shrimp or cleaner shrimp, is a commensal and often symbiotic genus of semi-transparent shrimp within the family Palaemonidae. Species of this large genus feature a wide variety of coloration and patterns, widespread distribution throughout much of the world's tropical oceans, and are often sought out for aquarium trade.