page_title: Porcupine ray
section_title: Human interactions
hierarchical_section_title: Porcupine ray / Human interactions
caption_attribution_description: Français&#160;: Gros plan sur la queue d'une raie porc-épic (Urogymnus asperrimus) aux Maldives (Landaagiraavaru, atoll de Baa). English: Close-up on the tail of a porcupine ray (Urogymnus asperrimus) in Maldives (Landaagiraavaru, Baa atoll).
context_page_description: The porcupine ray is a rare species of stingray in the family Dasyatidae. This bottom-dweller is found throughout the tropical Indo-Pacific, as well as off West Africa. It favors sand, coral rubble, and seagrass habitats in inshore waters to a depth of 30 m. A large and heavy-bodied species reaching 1.2–1.5 m in width, the porcupine ray has a nearly circular, plain-colored pectoral fin disc and a thin tail without any fin folds. Uniquely within its family, it lacks a venomous stinging spine. However, an adult ray can still defend itself ably with the many large, sharp thorns found over its disc and tail.
  The diet of the porcupine ray consists mainly of benthic invertebrates and bony fishes, which it digs up from the sea floor. It is aplacental viviparous, in which the developing embryos are nourished by histotroph produced by the mother. The porcupine ray has long been valued for its rough and durable skin, which was made into a shagreen leather once used for various utilitarian and ornamental purposes, such as to cover sword hilts and shields. It is caught incidentally by coastal fisheries.
context_section_description: Despite not having a sting, the porcupine ray is capable of injuring humans with its many sharp thorns. It is reportedly bold and tolerant of being approached closely underwater. The tough, thorny skin of this ray, made into a form of leather called shagreen, had many historical uses. In particular, it was used to cover the hilts of various melee weapons, as its extremely rough texture prevented slippage during battle. For example, the Japanese deemed it the only species whose skin was acceptable for covering sword grips. The Malayans used it to cover shields. The skin was also used ornamentally, such as by the Chinese, who dyed it and ground down the thorns to yield a mottled pattern. The native inhabitants of Funafuti Atoll used dried portions of the ray's tail as a rasp-like tool.
  Presently, the porcupine ray is caught incidentally in trawls, tangle nets, and beach seines. Its skin continues to be highly valued, while the meat and cartilage may also be used. In the Farasan Islands and some other places in the Red Sea, its liver is eaten as a seasonal dish. However, the economic importance of this ray is limited by how difficult it is to handle. The multispecies coastal fisheries that catch the porcupine ray are largely unregulated, which seems to have resulted in its dramatic decline or local extinction in the Bay of Bengal, the Gulf of Thailand, and likely elsewhere in its range. Potential additional threats to this species include habitat degradation from coastal development, and depletion of its food supply from overfishing. As a result, the International Union for Conservation of Nature has assessed it as vulnerable.
caption: Close-up on the tail of a porcupine ray (Landaa Giraavaru, Maldives)
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