Bluebridle Parrotfish (species: Scarus dimidiatus) in Lizard Island Field Guide (Lizard Island Field Guide)
Scarus dimidiatus
Bluebridle Parrotfish

©Renato Morais: Terminal phase Scarus dimidiatus at Horseshoe Reef, Lizard Island.

©Paul Asman: Terminal phase Scarus dimidiatus at Lizard Island. Note pair of oblique bands between eye and pectoral fin, purple above yellow/green.

©Anne Hoggett: Initial phase Scarus dimidiatus at lagoon bommie, Lizard Island.
Kingdom Animalia
Phylum Chordata
Class Actinopterygii
Order Perciformes
Family Scaridae
Genus Scarus
Species Scarus dimidiatus



Distinguishing features

Initial phase individuals are yellow with a grey head and three grey saddles on back. Terminal phase individuals are dark purple/blue at rear, front part of body is abruptly paler green/blue with a purple patch forward of the eye to the snout. Two oblique bands exend from the eye to the pectoral fin, a purple one above a yellow one. (Adapted from Allen et al, 2003).


  • Up to 22 cm (Length of initial phase (Allen et al, 2003))
  • Up to 30 cm (Length of terminal phase (Allen et al, 2003))

Depth range

  • Depth range data is not yet available.



©Atlas of Living Australia: Australian distribution

Web resources


References that assist with identification

  • Allen, G., R. Steene, P. Humann and N. Deloach (2003). Reef fish identification: Tropical Pacific New World Publications Inc., Jacksonville, FL, USA.
  • Bellwood, D.R. and J.H. Choat (1989). A description of the juvenile phase colour patterns of 24 parrotfish species (Family Scaridae) from the Great Barrier Reef, Australia, Records of the Australian Museum, 41: 1-41. LIRS catalog number 264.

Other references

  • Bellwood, D.R. (1985). The functional morphology, systematics and behavioural ecology of parrotfishes (Family Scaridae), Ph.D. thesis, James Cook University, Townsville. LIRS catalog number 310.
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