Fairy Basslet in Cozumel
Fairy Basslet (Gramma loreto) in Cozumel: how to identify it, where it is reliably seen, and what it is commonly confused with.
Purple at the front, yellow at the back, with a hard line between the two. Tiny, and usually upside down under a ledge — it orients its belly to the nearest surface, so on a cave roof it swims inverted.
Quick ID
| Scientific name | Gramma loreto |
|---|---|
| Group | Colourful Reef Fish |
| Typical size | Up to 8 cm |
| Depth range | 3–60 m |
| When to see it | Year-round |
| Active | Day |
| Conservation status | Least Concern |
How To Identify It
The front half is deep violet, the rear half golden yellow, with an abrupt transition and a dark stripe through the eye. Nothing else on a Caribbean reef looks like it.
Where You Will See It In Cozumel
Fairy Basslet works the 9 to 121 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 Mirador, El Presidente and Money Bar — all shore entries, so you dive them on your own schedule.
On an ordinary beginner boat dive. It should be within reach at Casa Blanca, Chankanaab Bolones, Columbia Shallows, El Cielo and La Francesa. No advanced certification needed.
Deeper, and on the walls. It is also plausible on Punta Tunich, San Francisco Wall, San Juan and Santa Rosa Wall.
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
Stays close to cover and orients to the nearest surface rather than to gravity, which is why they appear upside down under overhangs. They feed on zooplankton picked from the water just outside their shelter and dart back at any movement.
Commonly Confused With
- Royal gramma — The same fish. Fairy basslet and royal gramma are two names for Gramma loreto.
- Blackcap basslet — Purple with a black cap and no yellow rear.
Diving Etiquette And Safety
Keep fins off the reef and hands to yourself. Nothing here needs to be touched, moved or provoked to be seen well.
Part of the Cozumel marine life guide · see Cozumel dive sites · plan your Cozumel dive trip
Photo © Stephen Hoerler, courtesy of the Cozumel Coral Reef Restoration Program, used with permission.
Fairy Basslet Photos
Frequently Asked Questions
Why do fairy basslets swim upside down?
Is a fairy basslet the same as a royal gramma?
Where do you find fairy basslets in Cozumel?
Diving Cozumel soon?
Tell us your dates — we'll send options and connect you with the right dive shop.