The royal gramma or fairy basslet, Gamma loreto, is a member of the family Grammidae.
Although only three inches when fully grown, the vibrant purple and yellow colours of these shy fish make them stand out on the reef.
Native to the Caribbean, they prefer quiet, low-light overhangs on the coral reef in 50-100-foot depths. They have a propensity to swim upside down, darting out short distances to engulf passing plankton. They are also known to be cleaners of other reef fish, meaning they will pluck dead tissue and eat parasites off their bodies.
All royal grammas are born female, with one dominant fish in the small group becoming male.
It is always a treat to see divers doing headstands to have a good look at these beauties.
Tom Byrnes is the owner/operator of Cayman Marine Lab. He acquired his Coast Guard Captain’s Licence when he was a teenager and worked as a commercial fisherman in his youth. He got his first diving certificate in 1974 with the YMCA. He has worked in the local dive industry for more than 35 years and has a PhD in marine biology.