Foureye Butterflyfish in Cozumel

A pale disc with fine dark chevrons and one large dark eyespot ringed in white near the tail — plus a dark bar through the real eye. The false eye is the whole point of the name.

Quick ID

Where You Will See It In Cozumel

Foureye Butterflyfish works the 6 to 65 foot band. On this island that means the sheltered west-coast reefs, and the shallow east-side entries when the sea is flat — these are the sites where the depth and the habitat line up for it.

Without a boat. It is worth looking for at El Islote, El Mirador and El Presidente — all shore entries, so you dive them on your own schedule.

On an ordinary beginner boat dive. It should be within reach at Yucab, Casa Blanca, Chankanaab Bolones, Columbia Shallows and El Cielo. No advanced certification needed.

Deeper, and on the walls. It is also plausible on Palancar Bricks, Palancar Caves, Palancar Horseshoe and Paso del Cedral.

Conditions change the odds more than the site does — the current, the time of day and how much the group has already stirred up the sand. Ask your guide what they have been seeing that week.

Behaviour

Pairs for life and feeds on coral polyps and small invertebrates. The rear eyespot and the masked real eye are a matched pair of tricks: a predator aims at the wrong end and the fish escapes forwards.

Commonly Confused With

• Banded butterflyfish — Banded butterflyfish has bold black vertical bands and no rear eyespot.
• Spotfin butterflyfish — Spotfin is plainer with a small dark spot on the trailing dorsal fin.

Diving Etiquette And Safety

Nothing required.

Part of the Cozumel marine life guide · see Cozumel dive sites · plan your Cozumel dive trip

Photo: James St. John, CC BY 2.0, via Wikimedia Commons.