Scarus guacamaia Cuvier, 1829

Common Name and Size Rank

Scarus guacamaia (common name rainbow parrotfish) is the second largest parrotfish species, after the humphead parrotfish.

Size and Lifespan

It is the largest parrotfish found in the Atlantic, reaching up to 1.2 m (3.9 ft) in length, 20 kg in weight, and a maximum age of 16 years.

Coloration and Morphology

It has an overall greenish-brown colouration, with dull orange fins that feature green patches, and blue-green dental plates.

Sexual Dimorphism

Male and female individuals of this species look identical.

Closely Related Species

It is most closely related to two other large-bodied parrotfish species: Scarus coelestinus and Scarus trispinosus.

Distribution

This species has a relatively wide distribution across the western Atlantic, ranging from Bermuda, through South Florida, the Bahamas and the Caribbean, to Venezuela.

Habitat and Depth Range

It inhabits coral reefs, mangroves and sea grass beds in shallow waters, at depths between 3 and 25 m.

Diet

Scarus guacamaia is primarily a detritivore, feeding on detritus, bacterial colonies and meiofauna, though it also consumes sponges.

Juvenile Habitat

Young rainbow parrotfish mostly recruit to mangrove habitats.