Common Name: Threadfin Butterflyfish

Distribution: Common in Solitary Islands Marine Park. Widespread tropical Indo-Pacific, central Pacific from New South Wales to Japan, also east Africa and Red Sea. In Australia north Western Australia, across the tropical north through Queensland and south to central New South Wales, and including Lord Howe Island.

Ecological Notes: Frequents a variety of habitats from rich coral reefs to weedy and rubble covered areas. Juveniles in protected bays, estuaries, harbours and under jetties. Depth to at least 60 m.

Additional Notes: Adult fish have distinctive long filament trailing from top of dorsal fin and a large black blotch near trailing edge, with offset chevron pattern on side. Similar C. trifascialis has aligned chevron pattern without the black spot, C. vagabundus has offset chevron pattern and black bars in front of and on tail. Omnivorous, feeds primarily on small invertebrates, worms, coral polyps and algae. Small juvenile shown in bottom photograph. Grows to 23 cm.

References: R. Stuart-Smith, G. Edgar, A. Green, I. Shaw, Tropical Marine Fishes of Australia. Reed New Holland Publishers, 2015. p.201.

FishBase. Froese, R. and D. Pauly. Editors. 2018. World Wide Web electronic publication. http://fishbase.ca/summary/Chaetodon-auriga.html. Accessed 02/05/18.