''Ambassis jacksoniensis'', commonly known as the Port Jackson glassfish or Port Jackson perchlet, is a species of

fish A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...

in the family

Ambassidae The Asiatic glassfishes are a family, the Ambassidae, of freshwater and marine ray-finned fishes. Some species are known as perchlets. The family has also been called Chandidae, and some sources continue to use the name, but as Ambassidae was u ...

native to eastern Australia. It gains its common name from its transparent appearance.

Taxonomy

William John Macleay Sir William John Macleay (13 June 1820 – 7 December 1891) was a Scottish-Australian politician, naturalist, zoologist, and herpetologist. Early life Macleay was born at Wick, Caithness, Scotland, second son of Kenneth Macleay of Keiss and h ...

described the Port Jackson glassfish as ''Pseudambassis jacksoniensis'' in 1881 from a specimen collected in Port Jackson, noting that the length was three and a third times the fishes' height. The species name relates to the location it was described. It was classified in the new genus ''Velambassis'' by

Gilbert Whitley Gilbert Percy Whitley (9 June 1903 – 18 July 1975) was a British-born Australian Ichthyology, ichthyologist and malacologist who was curator of fishes at the Australian Museum in Sydney for about 40 years. Early life and education Gilbert Per ...

in 1935, on the basis of having weaker dorsal spines than other members of the family. Allen and Burgess found no reason for the species not to be in the genus ''

Ambassis ''Ambassis'' is a genus of ray-finned fish in the family Ambassidae, the Asiatic glassfishes. They are found widely in the Indo-Pacific region, with species in fresh, brackish and coastal marine waters. This genus includes fish known commonly as ...

'' and reassigned it there in 1990. This species and the co-occurring estuary glassfish ('' A. marianus'') are the only two members of the genus found in temperate waters. The others are found in the waters of northern Australia and southeast Asia.

Description

Reaching a

standard length Fish measurement is the measuring of individual fish and various parts of fish anatomy, their anatomies, for data used in many areas of ichthyology, including Taxonomy (biology), taxonomy and fishery biology. Overall length Standard length (SL) is ...

of , the Port Jackson glassfish has a silver and semi-transparent body and head covered with large cycloid scales. It has a short deeply-notched dorsal fin and forked tail fin. It is slimmer than the related ''A. marianus''—its body depth is 33 to 38% of standard length compared to the latter species' body depth of 37 to 44% of standard length. The Port Jackson glassfish also has a lateral line running the length of its body, while that of its relative is partial.

Distribution and habitat

The Port Jackson glassfish is native to coastal eastern Australia, from

Moreton Bay Moreton Bay is a bay located on the eastern coast of Australia from central Brisbane, Queensland. It is one of Queensland's most important coastal resources. The waters of Moreton Bay are a popular destination for recreational anglers and are ...

in Queensland through to

Narooma Narooma () is a town in the Australian state of New South Wales on the far south coast. The town is on the Princes Highway, which crosses the Wagonga Inlet to North Narooma. The heritage town of Tilba, New South Wales, Central Tilba is nearby t ...

in southern New South Wales. It lives in estuaries and protected brackish tidal streams that have mangroves growing along the margins.

Feeding

The Port Jackson glassfish feeds on

zooplankton Zooplankton are the heterotrophic component of the planktonic community (the " zoo-" prefix comes from ), having to consume other organisms to thrive. Plankton are aquatic organisms that are unable to swim effectively against currents. Consequent ...

, foraging from the water surface to the substrate. It is a food item of the little pied and

little black cormorant The little black cormorant (''Phalacrocorax sulcirostris'') is a member of the cormorant family of seabirds. It is common in smaller rivers and lakes throughout most areas of Australia and northern New Zealand, where it is known as the little bla ...

References

{{Taxonbar, from=Q1843701 Port Jackson glassfish Freshwater fish of Australia Port Jackson glassfish Taxa named by William John Macleay