Marine life identification guide > Pufferfish, porcupinefish & boxfish

Pufferfish, porcupinefish & boxfish species identification guide

You’ll find on this page species belonging to 3 closely related fish families: the Tetraodontidae (pufferfish), the Diodontidae (porcupinefish) and the Ostraciidae (boxfish, trunkfish). Puffers and porcupines are known for their capacity to puff up, while boxfish has kind of an exoskeleton, and sometimes small horns.

A fish able to “puff-up” when threatened

Pufferfish and porcupinefish are very easy to identify. They have the ability to “puff up” in a few seconds by swelling water if they are threatened or stressed. With this « balloon » shape, they appear much larger than they are, and are especially more difficult to bite for predators.

Blackspotted puffer
The blackspotted puffer, which can be light brown, grey, blue-grey or bright yellow, and sometimes grey with a yellow belly, is common on the coral reefs of the Indo-Pacific. Here, encountered in Lagon de la Saline, Réunion Island.

Porcupinefish also have large external spines, making them looking like “spiny balloons” when inflated. Most of the pufferfish species are also highly toxic: some parts of the fugu (species from the Takifugu genus), considered a delicacy in Japan, has enough poison to kill around thirty people.

Most species grow to 20 to 50cm in length, but the stellate pufferfish can grow to up to 120cm.

Boxfish have a more limited capacity to inflate themselves (only 20 to 30% of their volume), but have a very compact body, and can also release toxins in the event of aggression. They are a small family of around thirty species found in warm seas.

Where are pufferfish, porcupinefish and boxfish found?

Pufferfish, porcupinefish and boxfish are easy to spot when snorkeling the rocky beds and coral reefs of tropical and subtropical seas, often at very shallow depths.

The white-spotted puffer is common from the Red Sea to the Eastern Pacific, where it abounds on the rocky shores of Costa Rica. The guineafowl puffer, which is sometimes completely yellow, is also widely distributed on the reefs of the Indo-Pacific, for example in the lagoons of Reunion Island.

A snorkeler takes a picture of a yellow boxfish in Maldives
A snorkeler takes a picture of a yellow boxfish at Dhonveli‘s reef flat, Maldives.

If you snorkel in Egypt, Israel, or Jordan, you will certainly encounter the masked pufferfish, endemic to the Red Sea. Whilst pufferfish live mainly in saltwater, some species are also found in brackish water, such as the checkered puffer, commonly spotted at the edge of the mangroves in the Caribbean.

The long-spine porcupinefish and the spotfin porcupinefish are circumtropical, which means that they are present in all tropical seas of the planet.

In the Caribbean, the spotted trunkfish and the smooth trunkfish are both very common at shallow reefs. In the Indo-Pacific, you will often come across the yellow boxfish, whose juvenile exhibit an adorable bright yellow and black dots coloration.

The whitespotted boxfish, whose male and female have different colorations, is also common at many spots.

Caribbean & Western Atlantic species

Pufferfish, porcupinefish

Boxfish, trunkfish, cowfish

Indian & Pacific Oceans species

Pufferfish, porcupinefish

Boxfish, trunkfish, cowfish

Eastern Pacific Ocean species

Pufferfish, porcupinefish

Boxfish, trunkfish, cowfish

Mediterranean and Eastern Atlantic Ocean species


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