Common in the Solitary Islands Marine Park. Distributed throughout the Indo-Pacific region: from Cocos Island in the eastern Indian Ocean to the Line and Tuamoto islands, north to southern Japan. In Australia recorded from north of Shark Bay in Western Australia, the Coral Sea and the Great Barrier Reef in Queensland south to northern New South Wales and including Lord Howe Island.
Frequents reef slopes and flats, rocky shoreline, weed areas exposed to surge. Usually not deeper than 15 m.
Various stages similar colouration, juveniles and females have pink belly. Mature males have near horizontal pink line on cheek under eye which is enclosed by pink semicircular band starting from the eye and ending under the lower jaw, see top photograph. Juveniles difficult to distinguish from the similar H. nebulosus, sub adult pictured in lower photograph. More likely encountered in shallower surge zones around rocky reefs. Feeds on benthic crustaceans, molluscs, polychaetes, forams, fishes, and fish eggs. Grows to 12 cm.
R. Stuart-Smith, G. Edgar, A. Green, I. Shaw, Tropical Marine Fishes of Australia. Reed New Holland Publishers, 2015. p.311.
Atlas of Living Australia website at https://bie.ala.org.au/search?q=Halichoeres+margaritaceus. Accessed 30/05/18.
FishBase. Froese, R. and D. Pauly. Editors. 2018. World Wide Web electronic publication. https://fishbase.ca/summary/Halichoeres-margaritaceus.html. Accessed 30/05/18.