Centrolophus niger

The black ruff is a medusafish, the only member of the genus Centrolophus. It is a pelagic fish found in all tropical and temperate oceans at depths of 0 to 1,000 m. Its length is typically up to 60 cm (24 in), but it may reach 150 cm (60 in). Other common names include rudderfish and blackfish.

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