As its common name implies, the Spotted Sweetlips can be recognised by its spotted pattern that alters with growth.
Juvenile Harlequin Sweetlips under 7-8cm in length, are brown with large dark-edged, white spots (see bottom image). They swim with the head pointing down and with exaggerated fin movements resulting in an undulating motion. At this size the Harlequin Sweetlips is believed to be a nudibranch or flatworm mimic (see video). As juveniles grow, the brown base colour disappears and dark brown spots develop. Adults are white with dark brown spots on the body and fins.
Juveniles live in lagoons, but adults live in deeper water and are often observed under ledges or in caves.
This species is occurs in tropical marine waters of the Indo-West Pacific.
In Australia it is known from north-western Western Australia and the Great Barrier Reef.
The map below shows the Australian distribution of the species based on public sightings and specimens in Australian Museums. Source: Atlas of Living Australia.
Ozcam map of Spotted Sweetlips specimens in the Australian Museums. http://ozcam.ala.org.au/occurrences/search?q=Plectorhinchus%20chaetodonoides&zoom=off#mapView
- Allen, G.R. 1997. Marine Fishes of Tropical Australia and South-east Asia. Western Australian Museum. Pp. 292.
- Allen, G.R. & R. Swainston. 1988. The Marine Fishes of North-Western Australia. A Field Guide for Anglers and Divers. Western Australian Museum. Pp. 201.
- Kuiter, R.H. 1996. Guide to Sea Fishes of Australia. New Holland. Pp. 433.
- Randall, J.E., Allen, G.R. & R.C. Steene. 1997. Fishes of the Great Barrier Reef and Coral Sea. Crawford House Press. Pp. 557.