keeled boxfish

fish

Also known as: Aracanidae

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Last updated

June 30, 2026

Quick Summary

Keeled boxfish belong to the family Aracanidae and are related to the boxfish family, Ostraciontidae. These marine fish are found in warm, tropical seas worldwide. They are distinguished by a hard, boxlike carapace made of fused bony plates that covers most of their body, offering protection. Some species also have hornlike projections on their heads, leading to the alternative name "cowfish."

Keeled boxfish have a keel along their underside and openings behind their dorsal and anal fins. They are typically small, with the largest species reaching about 50 cm (20 inches) in length. While often attractively colored, boxfish can exude a toxic substance when handled, which can be lethal to other fish kept with them.1

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boxfish
…to the boxfishes are the keeled boxfishes of the family Aracanidae. These fishes also have a carapace, but there is a keel along the underside and openings behind the dorsal and anal fins. The members of this group are found from Japan to Australia.
Read More
…to the boxfishes are the keeled boxfishes of the family Aracanidae. These fishes also have a carapace, but there is a keel along the underside and openings behind the dorsal and anal fins. The members of this group are found from Japan to Australia.
Read More