Sydney Scorpionfish, Scorpaenopsis insperatus Motomura, 2004

Introduction

The Sydney Scorpionfish is a small fish that superficially looks like the Red Rockcod. Both species have 12 venomous dorsal fin spines and mottled reddish colouration.

Identification

It differs from the other species in the genus Scorpaenopsis by the presence of only one spine on the upper operculum and 30 to 34 scale rows along the side of the body.

Habitat

The species name insperatus is derived from Latin and means 'unexpected'. It refers to the unexpected discovery of this species in Sydney Harbour, a large waterbody that is surrounded by Australia's most populated city. Another unexpected aspect of the discovery of this fish was that fishes in the genus Scorpaenopsis are mostly found in tropical and subtropical waters. The Sydney Scorpionfish is found 850 km further south into temperate waters than all other species in the genus.

The two known specimens were collected on a course gravelly, sand bottom.

Distribution

Only two specimens of the Sydney Scorpionfish are currently known. They are the male holotype and one paratype. Both specimens were collected by M. Lockett, K. Parkinson and J. Pogonoski at a depth of 14 m at Chowder Bay, Sydney Harbour, New South Wales on 24 May 2001. The species was described by Dr Hiroyuki Motomura, who was a Postdoctoral Research Fellow at the Australian Museum, 2003-2005.

Chowder Bay is located close to the northern entrance to Sydney Harbour. The Royal Australian Navy restricts access to the area, and fishing, diving and swimming are prohibited. The fish were collected as part of a survey of exotic marine species in Sydney Harbour that was commissioned by the Sydney Ports Corporation. Museum staff and helpers sampled 57 sites, including the Chowder Bay location.

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

Unknown. Presumably a predator like other scorpionfishes.

Danger to humans

Rarely encountered, but like other scorpionfishes the dorsal spines are probably venomous.

References

1. Motomura, H. 2004. Scorpaenopsis insperatus: A new species of Scorpionfish from Sydney Harbour, New South Wales, Australia (Scorpaeniformes: Scorpaenidae). Copeia. 2004(3): 546-550.