The spikefishes (family Triacanthodidae) are ray-finned fishes related to the pufferfishes and triggerfishes. They live in deep waters, below 50 metres (160 ft), but above the continental shelves. They are found in the Atlantic, Indian Ocean, and the west-central Pacific. The spikefishes are quite variable in form, with some species having tubular snouts (greatly elongated in Halimochirurgus and Macrorhamphosodes), and others have spoon-like teeth for scraping the scales off other fishes. Depending on the exact species involved, they reach a maximum length of about 5 22 centimetres (2.0 8.7 in).