Bluehead Wrasse, Thalassoma amblycephalum (Bleeker, 1856)

Scientific name: Thalassoma amblycephalum
Alternative name/s:
Bluntheaded Wrasse, Two-tone Wrasse, Paddle-fin Wrasse
Bluehead Wrasse, Thalassoma amblycephalum Click to enlarge image
A Bluehead Wrasse at a depth of 13 m, North Solitary Island, New South Wales, 19 May 1997. Image: Ian Shaw
© Ian Shaw

Fast Facts

  • Classification
    Genus
    Thalassoma
    Species
    amblycephalum
    Family
    Labridae
    Order
    Perciformes
    Class
    Actinopterygii
    Subphylum
    Vertebrata
    Phylum
    Chordata
    Kingdom
    Animalia
  • Size Range
    The species grows to 16 cm in length.

Introduction

The Bluehead Wrasse changes colour as it grows. Juveniles and adults look very different.

Identification

The Bluehead Wrasse is an elongate species with a small mouth. There is a pair of canines at the front of both jaws. These are followed posteriorly by progressively smaller conical teeth. The caudal fin is truncate to emarginate becoming lunate in older males.

Initial phase fish are greenish to brownish above, and white below. They have a broad dark stripe along the side of the body. Terminal phase males have a bluish head followed posteriorly by a broad pale band in the pectoral region. The body is reddish with vertical green lines.

Distribution

The species occurs in tropical marine waters of the Indo-West and Central Pacific.

In Australia it is known from south-western to north-western Western Australia, and from the northern Great Barrier Reef, Queensland, south to southern New South Wales.

The map below shows the Australian distribution of the species based on public sightings and specimens in Australian Museums. Click on the map for detailed information. Source: Atlas of Living Australia.

Feeding and diet

It eats zooplankton.

References

  1. Allen, G.R. 1997. Marine Fishes of Tropical Australia and South-east Asia. Western Australian Museum. Pp. 292.
  2. Hutchins, B. & R. Swainston. 1986. Sea Fishes of Southern Australia. Complete Field Guide for Anglers and Divers. Swainston Publishing. Pp. 180.
  3. Kuiter, R.H. 2000. Coastal Fishes of South-eastern Australia. Gary Allen. Pp. 437.
  4. Randall, J.E., Allen, G.R. & R.C. Steene. 1997. Fishes of the Great Barrier Reef and Coral Sea. Crawford House Press. Pp. 557.