Reef stonefish

The reef stonefish is a master of disguise, a squat, warty fish that looks just like a rock or dead coral on the sea floor. It rarely moves, waiting for prey to wander close enough to grab in an instant.

Also known as: synanceia verrucosa, dornorn, goblinfish, stone fish, stonefish

The reef stonefish is built to look exactly like a lump of rock or dead coral, and most divers never see one lying still on the bottom. The best giveaway is the eyes: unlike a rock, a stonefish has two small eyes pointing upward, each sitting above a shallow pit in the head.

This is a wide, flat-headed fish with tough, rough skin covered in warts and no scales. Colours range from brown or grey to patches of yellow, orange, or red, all arranged to match the surrounding rock and rubble. Fleshy pectoral fins sit low on the body, and small eyes point upward from the top of the head, each set just above a shallow pit. Along its back runs a row of stout, equal-length spines, thickly sheathed at the base where its venom glands sit. It reaches a maximum length of 40 cm, though 27 cm is more typical.

The reef stonefish lives on coral reefs and sandy or rubble-strewn reef flats across the Indo-Pacific, from the Red Sea and East Africa to French Polynesia and southern Japan. It also turned up in the eastern Mediterranean in the 2010s, apparently arriving through the Suez Canal or from released aquarium fish. It rests directly on the seabed or settles among rocks and coral, sometimes lying in shallow tide pools or under a covering of algae.

This ambush predator feeds on small fish, shrimp, and other crustaceans. It stays completely still on the bottom, then strikes at incredible speed the instant prey swims within reach.

Reef stonefish live mostly alone, only coming together briefly with a mate during the breeding season. A female lays unfertilised eggs on the reef floor, and a male then fertilises them as he passes by; more than one male may do this with the same female. The eggs are large, and the young hatch already well developed. Females grow larger than males.

venomous

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  Bullrout

  Notesthes robusta

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  Cockatoo Waspfish

  Ablabys taenianotus

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  Estuarine Stonefish

  Synanceia horrida

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  Red Indianfish

  Pataecus fronto

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  South Australian Cobbler

  Gymnapistes marmoratus

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  Southern Velvetfish

  Aploactisoma milesii