Pascal Kobeh / Porcupinefish (Diodon holocanthus) close up skin detail, Sulu Sea, Philippines

Georgette Douwma / Freckled / Spiny porcupinefish (Diodon holocanthus) Lembeh, Sulawesi, Indonesia.

Georgette Douwma / Freckled or Spiny porcupinefish (Diodon holocanthus) with Funnel weed (Padina gymnospora) Lembeh, Sulawesi, Indonesia.

Pascal Kobeh / Close-up of Shortspine porcupinefish (Diodon holocanthus), coast of Dhofar and Hallaniyat islands, Oman. Arabian Sea.

Pascal Kobeh / Longspined porcupinefish / balloonfish (Diodon holocanthus) on reef, San Salvador Island / Colombus Island, Bahamas. Caribbean.

Pascal Kobeh / Longspined porcupinefish / balloonfish (Diodon holocanthus) Baja California peninsula, Mexico. Sea of Cortez.

Jeff Rotman / Short spined porcupine fish (Diodon holacanthus) in Lembeh Strait, Celebes Sea, Sulawesi, Indonesia.

Claudio Contreras / Balloonfish (Diodon holocanthus), Cabo Pulmo National Park, Sea of Cortez (Gulf of California), Mexico, July

Sue Daly / Long-spined porcupinefish (Diodon holocanthus) on wreck of the Rainbow Warrior, Cavalli Islands, New Zealand, February

MYN / Paul Marcellini / Longspined burrfish / Balloon fish (Diodon holocanthus) Florida, USA, November. meetyourneighbours.net project

MYN / Paul Marcellini / Longspined burrfish / Balloon fish (Diodon holocanthus) Florida, USA, November. meetyourneighbours.net project

Michele Westmorland / Balloon fish (Diodon holocanthus) on seabed, St Vincent, West-Indies, Caribbean, May.