Crab
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Crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" (Greek: brachy = short, ura = tail), or where the reduced abdomen is entirely hidden under the thorax. They are generally covered with a thick exoskeleton, and are armed with a single pair of chelae (claws). About 6000 species are known.[1] Crabs are found in all of the world's oceans. Additionally, there are also many freshwater and terrestrial crabs, particularly in tropical regions. Crabs vary in size from the pea crab, only a few millimetres wide, to the Japanese spider crab, with a leg span of up to 4 m.[2]
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[edit] Diet
Crabs are 8 legged omnivores, some feeding primarily on algae, others taking any type of food, including mollusks, worms, other crustaceans, fungi, bacteria and detritus, depending on their availability and the crab species. For many crabs, a mixed diet of plant and animal matter results in the fastest growth and greatest fitness.
[edit] Crab fishery
Crabs make up 20% of all marine crustaceans caught and farmed worldwide, with over 1½ million tonnes being consumed annually. Of that total, one species accounts for one fifth: Portunus trituberculatus. Other important taxa include Portunus pelagicus, several species in the genus Chionoecetes, the blue crab (Callinectes sapidus), Charybdis spp., Cancer pagurus, the Dungeness crab (Cancer magister) and Scylla serrata, each of which provides more than 20,000 tonnes annually [3].
[edit] Gallery
 Masked crab, Corystes cassivelaunus |
 Circular crab, Atelecyclus rotundatus |
 The terrestrial halloween crab, Geocarcinus ruricola |
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 Arrow crab Stenorhynchus seticornis |
 "Sally lightfoot", Grapsus grapsus |
 Thumbnail crab, Thia scutellata |
 Japanese spider crab, Macrocheira kaempferi |
.jpg/120px-Ocypode_quadrata_(2).jpg) Ghost crab, Ocypode quadrata |
 Fiddler crab, Uca pugnax |
 Lyreidus tridentatus, a raninid |
 Hepatus epheliticus, a calico crab |
 Crab larva (megalopa) |
[edit] Cultural influences of the crab
The Moche people of ancient Peru worshipped nature, especially the sea.[4] They placed emphasis on animals and often depicted crabs in their art.[5]
[edit] References
- ^ Walters, Martin & Johnson, Jinny. The World of Animals. Bath, Somerset: Parragon, 2007.
- ^ Biggest, Smallest, Fastest, Deepest: Marine Animal Records. OceanLink. Retrieved on September 22, 2006.
- ^ Global Capture Production 1950-2004. FAO. Retrieved on August 26, 2006.
- ^ Benson, Elizabeth, The Mochica: A Culture of Peru. New York, NY: Praeger Press. 1972
- ^ Berrin, Katherine & Larco Museum. The Spirit of Ancient Peru:Treasures from the Museo Arqueológico Rafael Larco Herrera. New York: Thames and Hudson, 1997.
