Common Silverbiddy, Gerres subfasciatus (Cuvier, 1830)

Scientific name: Gerres subfasciatus
Alternative name/s:
Common Silver Belly, Common Silverbelly, Ovate Silverbiddy, Roach, Silver Biddy, Silver-belly, Silverbelly, Silverbiddy, Southern Silverbiddy
Similar species:
Silverbelly (see Identification, above)
Silver Biddy, Gerres subfasciatus Click to enlarge image
A Silver Biddy at a depth of 4m, harbour entrance, Nambucca Heads, New South Wales, April 2000. Image: Erik Schlögl
© Erik Schlögl

Fast Facts

  • Classification
    Genus
    Gerres
    Species
    subfasciatus
    Family
    Gerreidae
    Order
    Perciformes
    Class
    Actinopterygii
    Subphylum
    Vertebrata
    Phylum
    Chordata
    Kingdom
    Animalia
  • Size Range
    The Common Silverbiddy grows to 20 cm in length.

Introduction

The Common Silverbiddy has a silver coloured body and highly protrusible jaws. The species occurs in estuaries and on coastal reefs in tropical and warm temperate areas of Australia.

Common Silverbiddy, Gerres subfasciatus

A Common Silverbiddy, Gerres subfasciatus, caught at Albion Park Rail, New South Wales, during the Lake Illawarra fieldtrip, May 2014.

Image: Mark McGrouther
© Australian Museum

Identification

The Common Silverbiddy has a silver coloured body and highly protrusible jaws. The dorsal fin is long based. Its anterior spines are black-tipped and are longer than those in the rest of the fin.

Like all fishes in the family Gerreidae, the jaws are highly protrusible. Both jaws can protrude out and down forming a tube. This adaptation to the mouth is used when the fish feeds on bottom-dwelling invertebrates.

Another species of Silver Biddy occurs in southern Australian waters - the Silverbelly Parequula melbournensis. This species is distinguishable from the Common Silverbiddy by its long-based anal fin and by the dorsal fin which is not elevated anteriorly.

I.45636-009 - Gerres subfasciatus

Gerres subfasciatus

Image: Mark McGrouther
© Australian Museum

Habitat

It lives in estuaries and on coastal reefs. It is usually observed in schools over sandy bottoms.

Distribution

The species occurs from south-western Western Australia, around the tropical north of the country, and south on the east coast to southern New South Wales.

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

References

  1. 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.
  2. Hutchins, B. & R. Swainston. 1986. Sea Fishes of Southern Australia. Complete Field Guide for Anglers and Divers. Swainston Publishing. Pp. 180. (as Roach)
  3. Kuiter, R.H. 1996. Guide to Sea Fishes of Australia. New Holland. Pp. 433.
  4. Kuiter, R.H. 2000. Coastal Fishes of South-eastern Australia. Gary Allen. Pp. 437.
  5. Yearsley, G.K., Last, P.R. & R.D. Ward. 1999. Australian Seafood Handbook, an identification guide to domestic species. CSIRO Marine Research. Pp. 461.