The silver sweep (''Scorpis lineolata''), also known as the false pompano, sweep, trumps or windawindawi, is a species of marine ray-finned fish from the

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end subfamily botanical names with "-oideae", and zoologi ...

Scorpidinae of the sea chub family Kyphosidae. It is native to the southwestern Pacific Ocean from Australia to New Zealand.

Description

The silver sweep has deep and strongly compressed body with a thin caudal peduncle. The head is moderately sized with an almost straight dorsal profile, a short snout and quite large eyes. The mouth is small and oblique with small but strong teeth in the jaws arranged in broad bands with the outer band being enlarged and recurved. Most of the body is covered in very small ctenoid scales and there is a gently curved

lateral line The lateral line, also called the lateral line organ (LLO), is a system of sensory organs found in fish, used to detect movement, vibration, and pressure gradients in the surrounding water. The sensory ability is achieved via modified epithelial ...

. The dorsal fin continuous with a very short first spine, there are a 10 spines which progressively become higher towards the tail, the first rays in the soft-rayed portion of the dorsal fin is only slightly higher than the spiny portion giving the dorsal fin an almost straight profile. The soft-rayed part of the dorsal fin contains 26-28 soft rays. The

anal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...

has 3 spines and 27-28 soft rays. The soft portion of the dorsal fin is notably longer than they spiny portion. It has small pectoral fin are small with the uppermost rays being the longest. The

pelvic fin Pelvic fins or ventral fins are paired fins located on the ventral surface of fish. The paired pelvic fins are homologous to the hindlimbs of tetrapods. Structure and function Structure In actinopterygians, the pelvic fin consists of two en ...

s are also small and are located below and to the rear of the pectoral fins. Silver sweeps are greyish, blue-grey or green-grey dorsally and silver-grey ventrally, with the edge of the gill cover and the base of the pectoral fin being blackish. This species can reach a length of .

Distribution

The silver sweep is found in the southwestern Pacific Ocean off Australia and New Zealand. In Australia it is found from Moreton Bay in Queensland south to Tasmania and west as far as Victor Harbor, South Australia. It is also found in the Tasman Sea around Lord Howe Island and

Norfolk Island Norfolk Island (, ; Norfuk: ''Norf'k Ailen'') is an external territory of Australia located in the Pacific Ocean between New Zealand and New Caledonia, directly east of Australia's Evans Head and about from Lord Howe Island. Together with ...

. Silver sweep are a common fish on the east coast of Australia, particularly in New South Wales. In New Zealand silver sweep are distributed around the coast of the

North Island The North Island, also officially named Te Ika-a-Māui, is one of the two main islands of New Zealand, separated from the larger but much less populous South Island by the Cook Strait. The island's area is , making it the world's 14th-largest ...

Habitat and biology

Adult silver sweeps are found on coastal reefs at depths down to at least , It feeds on plankton over rock reefs where it forms schools while juveniles settle in tide pools and can be found in the brackish waters of estuaries. They spawn in the winter with the peak breeding season between May and August. The eggs are pelagic. The young fish grow very quickly for the first 2–3 years but growth slows down significantly after sexual maturity, although they may live over 50 years. Silver sweeps have separate sexes.

Taxonomy

The silver sweep was first formally described by the

Austrian Austrian may refer to: * Austrians, someone from Austria or of Austrian descent ** Someone who is considered an Austrian citizen, see Austrian nationality law * Austrian German dialect * Something associated with the country Austria, for example: ...

ichthyologist Ichthyology is the branch of zoology devoted to the study of fish, including bony fish ( Osteichthyes), cartilaginous fish (Chondrichthyes), and jawless fish (Agnatha). According to FishBase, 33,400 species of fish had been described as of Octobe ...

Rudolf Kner in 1865 with the type locality given as

Sydney Sydney ( ) is the capital city of the state of New South Wales, and the most populous city in both Australia and Oceania. Located on Australia's east coast, the metropolis surrounds Sydney Harbour and extends about towards the Blue Mountain ...

in New South Wales.

Fisheries

The silver sweep is of secondary importance as a target for commercial fisheries and is caught using

purse seine Seine fishing (or seine-haul fishing; ) is a method of fishing that employs a surrounding net, called a seine, that hangs vertically in the water with its bottom edge held down by weights and its top edge buoyed by floats. Seine nets can be dep ...

s and trap nets. Since 1997-98 the amount landed in New South Wales has declined from nearly 15t to less than 50t. About 60t are caught annually in New South Wales by recreational fishermen. The flesh of the silver sweep is said to be firm and of excellent quality.

References

{{Taxonbar, from=Q2611007

Silver sweep The silver sweep (''Scorpis lineolata''), also known as the false pompano, sweep, trumps or windawindawi, is a species of marine ray-finned fish from the subfamily Scorpidinae of the sea chub family Kyphosidae. It is native to the southwestern ...

Taxa named by Rudolf Kner Fish described in 1865