Macrophthalmus | |
---|---|
Macrophthalmus japonicus | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Malacostraca |
Order: | Decapoda |
Suborder: | Pleocyemata |
Infraorder: | Brachyura |
Family: | Macrophthalmidae |
Subfamily: | Macrophthalminae |
Genus: | Macrophthalmus Desmarest, 1823 |
Type species | |
Goneplax transversus Latreille, 1817 |
Macrophthalmus is a genus of crabs which are widespread across the Indo-Pacific. [1] It contains the following species (arranged into subgenera): [2] Species in this genus are often referred to as sentinel crabs.
The fiddler crab or calling crab can be one of the hundred species of semiterrestrial marine crabs in the family Ocypodidae. These crabs are well known for their extreme sexual dimorphism, where the male crabs have a major claw significantly larger than their minor claw, whilst females claws are both the same size. The name fiddler crab comes from the appearance of their small and large claw together, looking similar to a fiddle.
Xanthidae is a family of crabs known as gorilla crabs, mud crabs, pebble crabs or rubble crabs. Xanthid crabs are often brightly coloured and are highly poisonous, containing toxins which are not destroyed by cooking and for which no antidote is known. The toxins are similar to the tetrodotoxin and saxitoxin produced by puffer fish, and may be produced by bacteria in the genus Vibrio living in symbiosis with the crabs, mostly V. alginolyticus and V. parahaemolyticus.
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:
Majidae is a family of crabs, comprising around 200 marine species inside 52 genera, with a carapace that is longer than it is broad, and which forms a point at the front. The legs can be very long in some species, leading to the name "spider crab". The exoskeleton is covered with bristles to which the crab attaches algae and other items to act as camouflage.
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.
Callianassa is a genus of mud shrimps, in the family Callianassidae. Three of the species in this genus have been split off into a new genus, Pestarella, while others such as Callianassa filholi have been moved to Biffarius. The genus is named after the Nereid of the Greco-Roman mythology.
Pagurus is a genus of hermit crabs in the family Paguridae. Like other hermit crabs, their abdomen is not calcified and they use snail shells as protection. These marine decapod crustaceans are omnivorous, but mostly prey on small animals and scavenge carrion. Trigonocheirus and Pagurixus used to be considered subgenera of Pagurus, but the former is nowadays included in Orthopagurus, while the latter has been separated as a distinct genus.
The Varunidae are a family of thoracotrematan crabs. The delimitation of this family, part of the taxonomically confusing Grapsoidea, is undergoing revision. For a long time, they were placed at the rank of subfamily in the Grapsidae, but they appear to be closest to Macropthalmus and the Mictyridae, which are usually placed in the Ocypodoidea. It may thus be better to merge the latter superfamily with the Grapsoidea, retaining the latter name as it is older.
Paguristes is a genus of hermit crab in the family Diogenidae. It includes the following species :
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.
Etisus is a genus of crabs, containing the following extant species:
Leucosiidae is a family of crabs containing three subfamilies and a number of genera incertae sedis:
Pilodius is a genus of crabs in the family Xanthidae, containing the following species:
Liomera is a genus of crabs in the family Xanthidae. It contains the following species:
Pilumnus is a genus of crabs, containing the following species:
Pisinae is a subfamily of crabs in the family Epialtidae, comprising the following genera:
Pachycheles is a genus of porcelain crabs in the family Porcellanidae. There are more than 40 described species in Pachycheles.
Xiphonectes is a genus of crabs within the family Portunidae. Members of this genus are found distributed in the Indian and Pacific Ocean.