Juvenile Hairtail Blenny Click to enlarge image
A juvenile Hairtail Blenny in an aquarium. The fish was caught close to the surface during a fieldtrip to Lizard Island over January and February 2008. Image: Colin Wen
© Colin Wen

Fast Facts

  • Classification
  • Size Range
    The species grows to 53 cm in length.


The Hairtail Blenny is a very elongate banded fish that has an enormous fang on either side of the lower jaw.


The Hairtail Blenny has a long eel-like body with a high dorsal fin originating in front of the eyes. It has large eyes and two enormous curved fangs, one on either side near the front of the lower jaw.

This species is brownish-yellow with a series of brown bars. There is a blue-edged black ocellus anteriorly on the dorsal fin.


The Hairtail Blenny occurs on sandy or muddy substrates where it lives in the burrows of other fishes. It is also known to swim in open water.

Jeff Johnson stated that in March 2016 he identified several Xiphasia setifer from gut contents of Mahi Mahi caught around a FAD off Shellharbour, New South Wales. He stated that "I have had reports previously that Xiphasia are not confined to bottom-dwelling in burrows and often hang around floating objects in open water. Hence, not so strange that they would be taken by Mahi Mahi". See another report of predation by Mahi Mahi under 'Predators, Parasites and Diseases, below.

Amanda Hay reported that "We occasionally caught Xiphasia in light traps, so they definitely occur in mid-waters".


The Hairtail Blenny is found in tropical and warm temperate marine waters of the Indo-West Pacific. In Australia it is recorded from the central coast of Western Australia, around the tropical north and 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.

Other behaviours and adaptations

It enters burrows tail first. Divers usually see just the head of this fish projecting from the sand.


In May 2013, Marine Ranger, Jimmy Maher from the Lord Howe Island Marine Park sent images to the museum of Hairtail Blenny specimens that were removed from the stomach of a Mahi Mahi.


  1. Allen, G.R. 1997. Marine Fishes of Tropical Australia and South-east Asia. Western Australian Museum. Pp. 292.
  2. Kuiter, R.H. 1996. Guide to Sea Fishes of Australia. New Holland. Pp. 433.
  3. Randall, J.E., Allen, G.R. & R.C. Steene. 1997. Fishes of the Great Barrier Reef and Coral Sea. Crawford House Press. Pp. 557.