Flyspecked Hardyhead, Craterocephalus stercusmuscarum (Günther, 1867)

Scientific name: Craterocephalus stercusmuscarum
Alternative name/s:
Freshwater Hardyhead, Freshwater Silverside, Line-eye, Mitchellian Hardyhead, Northern Fresh Water Hardyhead, Speckled Crat, Worrell's Freshwater Hardyhead
Similar species:
The related Unspecked Hardyhead, Craterocephalus fulvus, was originally described as a subspecies of C. stercusmuscarum. This species occurs in coastal drainages from southern Queensland to northern New South Wales and the Murray-Darling River system.
A Fly-specked Hardyhead, Craterocephalus stercusmuscarum at SA Click to enlarge image
A Fly-specked Hardyhead at Sydney Aquarium. Image: Stuart Humphreys
© Australian Museum

Fast Facts

  • Classification
    Genus
    Craterocephalus
    Species
    stercusmuscarum
    Family
    Atherinidae
    Order
    Atheriniformes
    Class
    Actinopterygii
    Subphylum
    Vertebrata
    Phylum
    Chordata
    Kingdom
    Animalia
  • Size Range
    It grows to about 8 cm in length.

Introduction

The Flyspecked Hardyhead has a slender body covered with black dots. The species is endemic to Australia. It occurs in some freshwater streams of the Northern Territory to southern Queensland.

Identification

The Flyspecked Hardyhead has a slender body covered with black dots. This pattern gave rise to the common name. The fish is golden yellow to deep green above, changing to white below. A dusky to silver stripe runs from the snout to the caudal peduncle.

Fly-specked Hardyhead, Craterocephalus stercusmuscarum

A school of Flyspecked Hardyheads at Sydney Aquarium

Image: Stuart Humphreys
© Australian Museum

Distribution

The species is endemic to Australia. It occurs in some freshwater streams of the Northern Territory to southern Queensland.

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

Feeding and diet

The Flyspecked Hardyhead eats mainly mosquito larvae and aquatic insects. It will also eat crustaceans and has been observed eating algae in aquaria.

Economic impacts

It can be easily kept in aquaria but its natural colours often fade.

References

  1. Allen, G.R. 1989. Freshwater Fishes of Australia. T.F.H. Publications. Pp. 240. Ivantsoff, W. & L.E.L.M. Crowley. in McDowall, R.M. 1996. Freshwater Fishes of South-Eastern Australia. Reed Books. Pp. 247.
  2. Hoese, D.F., Bray, D.J., Paxton, J.R. & G.R. Allen. 2006. Fishes. In Beesley, P.L. & A. Wells. (eds) Zoological Catalogue of Australia. Volume 35. ABRS & CSIRO Publishing: Australia. parts 1-3, pages 1-2178.
  3. Merrick, J.R. & G.E. Schmida. 1984. Australian Freshwater Fishes. Biology and Management. John R. Merrick. Pp. 409.