page_title: Porcupine ray
section_title: Biology and ecology
hierarchical_section_title: Porcupine ray / Biology and ecology
caption_attribution_description: English: Porcupine Ray - Vilamendhoo Island Lagoon - Maldives
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: The porcupine ray can sometimes be observed lying still on the bottom in the open or inside caves. It is known to form groups at Ningaloo Reef. Its diet consists primarily of sipunculids, polychaete worms, crustaceans, and bony fishes. When feeding, it plows deeply into the bottom, expelling excess sediment from its spiracles in a plume visible from a long distance away. Parasites documented from this ray include the tapeworm Rhinebothrium devaneyi, the nematode Echinocephalus overstreeti, and the capsalid monogeneans Dendromonocotyle urogymni and Neoentobdella baggioi. The porcupine ray is aplacental viviparous, with the developing embryos sustained to term by histotroph ("uterine milk") secreted by the mother. Mangrove forests serve as important habitat for juvenile rays. Males and females mature sexually at about 90 and 100 cm (35 and 39 in) across, respectively.
caption: Porcupine ray digging itself into the sand of the lagoon, eating what it finds
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