Pennantfish, Alectis ciliaris (Bloch, 1787)

Introduction

Juvenile Pennantfish have beautiful trailing filaments from the dorsal and anal fins. Individuals are sometimes seen swimming next to wharves and docks around the Sydney region.

Identification

Juvenile Pennantfish have very elongate trailing filaments from the dorsal and anal fins. These are not present in adults.

Two species of Alectis are known from Australian waters. The Juvenile Diamond Trevally, Alectis indica, can be distinguished from the Pennantfish by the presence of filaments on the pelvic fins. The Adult Pennantfish has a more rounded upper head profile than the angular head of the Diamond Trevally.

Habitat

It is a pelagic species that lives in inshore and continental shelf waters from the surface to about 100 m.

Distribution

The Pennantfish occurs circumglobally in tropical and some temperate waters

In Australia it is known from south-western Western Australia, around the tropical north of the country to the southern coast of 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. Allen, G.R. & R. Swainston. 1988. The Marine Fishes of North-Western Australia. A Field Guide for Anglers and Divers. Western Australian Museum. Pp. 201.
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. Sainsbury, K.J., Kailola, P.J., & G.G. Leyland. 1985. Continental Shelf Fishes of northern and north-western Australia. An illustrated Guide. CSIRO Division of Fisheries Research. Pp. 375.