| Charybdis feriata | |
|---|---|
 | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Subphylum: | Crustacea |
| Class: | Malacostraca |
| Order: | Decapoda |
| Suborder: | Pleocyemata |
| Infraorder: | Brachyura |
| Family: | Portunidae |
| Genus: | Charybdis |
| Species: | C. feriata |
| Binomial name | |
| Charybdis feriata | |
| Synonyms [1] | |
| |
Charybdis feriata, the crucifix crab, is a species of swimming crab in the family Portunidae. [1] It is found in the tropical and subtropical Indo-Pacific region.
This crab grows to a width of about 20 cm (8 in). The body is fan-shaped and the carapace is smooth, with some granular transverse lines. The front of the carapace bears six triangular teeth of similar size, and each side of the carapace bears six larger, truncated teeth which vary in size. The eyes are close together. There are three spines on the carpus of the cheliped (pincer leg), and smaller spines on the other joints. The hindmost pair of pleopods (walking legs) are paddle-shaped and are used in propulsion when swimming. The carapace is boldly patterned in cream and brown, and often bears a distinctive white cross on a dark background in the centre. The pincers are brown with white patches and the legs have brown and white bands. [2] [3]
This crab gets its common name from the cross-shaped mark on the carapace. Tradition has it that the Jesuit priest Francis Xavier lost his crucifix during a storm in Indonesia, possibly when he was trying to calm the waters. On the following day, while he was on the shore, a crab emerged from the sea holding his crucifix in its pincers. Saint Francis blessed the crab, and ever since, it has borne the mark of the cross on its shell. Some Catholics venerate the crab, and the shells are sometimes sold as religious trinkets or good luck charms. [4]
Charybdis feriata is native to the tropical and subtropical western Indo-Pacific region. Its range extends from East Africa, the Red Sea and the Persian Gulf to Japan, Indonesia and Australia. It is uncommon in Australia but is harvested commercially in parts of its range such as India. [4]
In February 2022, a female specimen was caught by some fishermen off the Genoese coast, in the area in front of the Lanterna, at a depth of about 50 meters using a lobster trammel net. Reported to the "DISTAV Fishing Biology Laboratory" of the University of Genoa, the specimen is transported to the Mediterranean department of the Genoa Aquarium, to be transferred to the curatorial tanks and to observe its behavior. This was not the first report of sighting or capture of this species of crab in the Mediterranean Sea, it had already been reported for the first time in 2004 in Spain, in the seas of Barcelona, the second in Livorno in 2015 and the third still in Spain, near Tarragona in 2017. [5]
Charybdis feriata inhabits shallow water, on both rocks and sandy bottoms. [4] Mating takes place between a hard-shelled male crab and a soft-shelled, freshly-moulted female crab. The male takes up a guarding "cradle" position before the female moults, straddling her and gripping her with his ambulatory legs. He dismounts while she is moulting, helping her to detach the old shell, before adopting the cradle position once more. Copulation is initiated a few hours later; the male turns the female over with his chelipeds and walking legs. She then positions herself underneath him, but facing in the opposite direction, with her abdomen extended and he inserts his gonopods into her genital openings. This position is maintained for about seven hours, during which time the male may walk around with the female attached. Afterwards the male adopts the cradle position again for a few hours, while she remains inactive until her shell has hardened. Spawning takes place about 17 days later, and as is the case with other crabs, the female carries the fertilised eggs under her abdomen. [6]
Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" (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. They first appeared during the Jurassic Period.
Cancer pagurus, commonly known as the edible crab or brown crab, is a species of crab found in the North Sea, North Atlantic Ocean, and perhaps the Mediterranean Sea. It is a robust crab of a reddish-brown colour, having an oval carapace with a characteristic "pie crust" edge and black tips to the claws. A mature adult may have a carapace width up to 25 centimetres and weigh up to 3 kilograms. C. pagurus is a nocturnal predator, targeting a range of molluscs and crustaceans. It is the subject of the largest crab fishery in Western Europe, centred on the coasts of the British Isles, with more than 60,000 tonnes caught annually.
The decapod is made up of 20 body segments grouped into two main body parts: the cephalothorax and the pleon (abdomen). Each segment may possess one pair of appendages, although in various groups these may be reduced or missing. They are, from head to tail:
Portunus pelagicus, also known as the flower crab, blue crab, blue swimmer crab, blue manna crab or sand crab, rajungan in Indonesian, and alimasag in Tagalog, Kapampangan, and Pangasinan, is a large crab found in the Indo-Pacific, including off the coasts of Indonesia, Cambodia, Thailand, the Philippines, and Vietnam; and in the intertidal estuaries around most of Australia and east to New Caledonia.
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.
Charybdis is a genus of swimming crabs in the family Portunidae; "Charybdis" is Greek for whirlpool.
Notomithrax ursus, known as the hairy seaweed crab, is a spider crab of the family Majidae.
Tachypleus tridentatus, commonly known as the Chinese horseshoe crab, Japanese horseshoe crab, or tri-spine horseshoe crab, is a species of horseshoe crab found in Southeast and East Asia, with records from China, Indonesia, Japan, South Korea, Malaysia, the Philippines, Taiwan, and Vietnam. It is found in coastal marine and brackish waters, and tolerates colder temperatures than the other Asian horseshoe crabs, although juveniles still need water warmer than 22 °C (72 °F) to moult.
Cancer productus, one of several species known as red rock crabs, is a crab of the genus Cancer found on the western coast of North America. This species is commonly nicknamed the Pearl of the Pacific Northwest.
Goneplax rhomboides is a species of crab. It is known by the common name angular crab because of its angular carapace. Although it is also called the square crab, its shell is in fact more trapezoidal than square. This species is also known as the mud-runner because they are able to run away quickly when threatened.
The coconut crab is a species of terrestrial hermit crab, also known as the robber crab or palm thief. It is the largest terrestrial arthropod in the world, with a weight of up to 4.1 kg (9 lb). It can grow to up to 1 m in width from the tip of one leg to the tip of another. It is found on islands across the Indian Ocean, and parts of the Pacific Ocean as far east as the Gambier Islands, Pitcairn Islands and Caroline Island, similar to the distribution of the coconut palm; it has been extirpated from most areas with a significant human population, including mainland Australia and Madagascar. Coconut crabs also live off the coast of Africa near Zanzibar.
Dromia personata, also known as the sponge crab or sleepy crab, is a species of crab found in the North Sea, the Mediterranean Sea, and connecting parts of the northeastern Atlantic Ocean. Like most other epibenthic crustaceans, the biomass of this species is especially dense in the Mediterranean continental shelf. It mainly resides from the lower shore to a depth of 50 meters (164 ft), often in caves. Occasionally, they are found living in depths as low as 110 meters (360 ft). They serve as prey for octopus, starfish, and other fish. Their last two pairs of legs are positioned dorsally, and are used to hold a sponge in place as camouflage.
Pisidia longicornis, the long-clawed porcelain crab, is a species of porcelain crab that lives in the north-eastern Atlantic Ocean. It varies from reddish to white, and grows to a carapace width of 1 cm (0.4 in). It was first named by Carl Linnaeus in 1767, although the etymology remains unclear.
Chionoecetes opilio, a species of snow crab, also known as opilio crab or opies, is a predominantly epifaunal crustacean native to shelf depths in the northwest Atlantic Ocean and north Pacific Ocean. It is a well-known commercial species of Chionoecetes, often caught with traps or by trawling. Seven species are in the genus Chionoecetes, all of which bear the name "snow crab". C. opilio is related to C. bairdi, commonly known as the tanner crab, and other crab species found in the cold, northern oceans.
Oregonia gracilis, commonly known as the graceful decorator crab, is a species of crab belonging to the family Oregoniidae. Like other decorator crabs it habitually attaches other organisms to its back. The sessile organisms are attached to hooked setae that act as a sort of velcro attachment. This decoration provides visual and chemical camouflage thus reducing predation risk. Pacific halibut are a major predator of O. gracilis. Other predators include octopus and sea otters. The main food source of O. gracilis is floating kelp and algae that they capture utilizing a waiting strategy in order to maintain cryptosis.
Macropodia rostrata, common names, the common spider crab, long-legged spider crab, long-legged crab, is a species of marine crab in the family Inachidae. The Macropodia Rostrata visually mimics many other types of small crabs with the exception of its long legs. By attaching algae to their thin legs, they can be confused with the stem of seaweed. This is both a defense mechanism and a predatory advantage, as unsuspecting fish will hide in seaweed beds from nearby predators. This behavior can be absent among larger crabs, and those that live at great depths like giant Japanese spider crabs.
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.
Charybdis natator, the ridged swimming crab, wrinkled swimming crab or rock crab, is a widespread Indo-Pacific species of swimming crab from the genus Charybdis. It gets its name from the ridges on the dorsal surface of the carapace. It is a crab species which is of minor importance in fisheries.
Charybdis hellerii, the Indo-Pacific swimming crab or spiny hands is a species of crab from the swimming crab family, the Portunidae. Its native range covers the Indian and Pacific Oceans but it has been introduced to the western Atlantic and has invaded the Mediterranean. It is a commercially exploited species in south-east Asia.