| Ranina ranina | |
|---|---|
 | |
Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Malacostraca |
| Order: | Decapoda |
| Suborder: | Pleocyemata |
| Infraorder: | Brachyura |
| Family: | Raninidae |
| Genus: | Ranina |
| Species: | R. ranina |
| Binomial name | |
| Ranina ranina | |
| Synonyms[1] | |
| |
Ranina ranina, also known as theHuỳnh Đế crab,[2](red) frog crab orspanner crab,[3] is aspecies ofcrab[4] found throughouttropical andsubtropicalhabitats.[5] It is often fished for its meat.[6]
It may grow up to 15.0 centimetres (5.9 in) long, and may weigh up to 900 grams (2.0 lb).[7] Thecarapace is wider at the front, reddish brown in color, with ten white spots.[5]Ranina ranina is mainlynocturnal, and remains buried in thesand during the day.[3]Ranina ranina is easily distinguished from other crab species in its habitat due to its red carapace and elongated midsection.[7]
Spanner crabs inhabit coastal waters along the east coast of Australia, from Yeppoon in Queensland to the North coast of New South Wales. There is also a population to the north of Perth in Western Australia.[7]Ranina ranina is abundant in the coastal waters of south-western Mindanao, Philippines. These crabs are also found in the eastern coast of Africa, across the Indian Ocean to Indonesia, Japan and Hawaii and Vietnam.[8]
Ranina ranina inhabits depths of 10–100 metres (33–328 ft) on sandy-smooth substrata in which they bury themselves from where they attack small bottom-dwelling fish.[9] When waiting for prey,Ranina ranina will cover itself with sand, but leave its eye and mouthparts sticking out to help detect its food.[3] Offshore areas within this range in a subtropical or tropical environment serves as a habitat forRanina ranina, but they must have ample sand forRanina ranina to flourish, as covering themselves in sand is instrumental in their method of catching prey. The Ranina Ranina crab is a popular species of crab that gets fished, in Australia, 96% of the female crab doesn’t get fished. In one location during spawning season, the decrease in females being hunted doesn’t apply. Meaning that the specific area of Tallows Beach is the focus of spawning migration.
The species is commercially exploited over much of itsrange, but the largest fishery is in Australia, where the annual commercial catch an estimated at 3,592 tonnes (7,919,000 lb).[5][10] InQueensland, only adults above 100 mm (3.9 in)carapace length may be landed.[11] In thePhilippines in 2008, prices forRanina ranina were around 200–300pesos perkilogram.[5]Ranina ranina populations have been surveyed to avoidoverfishing and are currently stable.[12]
AlthoughRanina ranina is a target of commercial fishing operations, little is known about the species' biology, population dynamics and ecology.[11] Attempts have been made to growRanina ranina in captivity, but have so far been met with little success.[3]
Ranina ranina is a regional specialty in some regions of the Philippines where it is known ascuracha. It is generally eaten steamed ashalabos, or cooked in coconut milk asginataan. A notable variant of the latter is thecuracha Alavar ofZamboanga City.[13][14]
In Vietnam the species is named as "Huỳnh Đế crab", literally means "emperor crab". The names refer to the fact thatR. ranina is one of the favorite high-ranked cuisine of historical Vietnamese monarchs.[15] It is the delicacy harvested in the provincesBình Định andQuảng Ngãi, and is hailed "monarch of all the crab".[16]
Media related toRanina ranina at Wikimedia Commons
Data related toRanina ranina at Wikispecies