Colours

Distinguishing features

A small to medium sized parrotfish that can have considerable colour variation. Terminal phase males are generally lime-green with a yellowish patch toward the tail. The dorsal, ventral and tail fins are blue, while the pectoral fin is green with a thin purple stripe. The scales are edged with purple. The fish can however darken its colour to a brownish-green from time to time (see image below). The initial phase fish are generally dark maroon-brown with pink around the lips, and often with a double row of 4 white spots along the side. These fish can too change colour, with a lighter colour pattern frequently seen in the larger IP fish. The juvenile is dark brown with a series of horizontal white stripes

Size

Depth range

Synonyms

Similar taxa

Distribution

Distribution and habitat preferences

Possibly the most common Scarid at Lizard Island, it is found in nearly all habitats, but most common on shallow flats and lagoonal and backreef patch reefs.

Found in most locations around the Island.

Behaviour

The Greenfin Parrotfish, along with others from the genus Chlorurus, have exposed teeth in powerful jaws, and they use an excavating mode of feeding. They take benthic turf algae from dead coral surfaces, and due to their high numbers are considered important agents of bioerosion. Spawning takes place in the summer months at reef passes and points with good water flow. This species reaches 8-9 years of age, with both males and females present in the initial phase, but only males in the green terminal phase. There are strong differences in the demography of this species between Lizard Island and the outer barrier reef. Population density at Lizard is 50% lower than at the outer barrier, however fish at Lizard grow faster, live longer, and suffer less mortality.

Web resources

References