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Deeply keeled, compressed bodies and large eyes typify sweepers, their form somehwat like [[hatchetfish]]; both cycloid and ctenoid [[scale (zoology)|scale]]s may be present. The small, short [[dorsal fin]] begins before the body's midpoint and may have 4-7 spines; the [[anal fin]] is extensive and usually has 3 spines. The mouth is subterminal and strongly oblique. Species of the genus ''[[Parapriacanthus]]'' have much more cylindrical bodies.
Deeply keeled, compressed bodies and large eyes typify sweepers, their form somehwat like [[hatchetfish]]; both cycloid and ctenoid [[scale (zoology)|scale]]s may be present. The small, short [[dorsal fin]] begins before the body's midpoint and may have 4-7 spines; the [[anal fin]] is extensive and usually has 3 spines. The mouth is subterminal and strongly oblique. Species of the genus ''[[Parapriacanthus]]'' have much more cylindrical bodies.


Some species possess [[photophore]]s. All but the [[Curved Sweeper]] (''Pempheris poeyi'') possess a [[gas bladder]]. The largest species is the [[Common Bullseye]] (''Pempheris multiradiata'') at 28 centimetres in length; most other species measure 16 centimetres or less. Coloration is relatively subdued.
Some species possess [[photophore]]s. All but the [[curved sweeper]] (''Pempheris poeyi'') possess a [[gas bladder]]. The largest species is the [[common bullseye]] (''Pempheris multiradiata'') at 28 centimetres in length; most other species measure 16 centimetres or less. Coloration is relatively subdued.


== Behaviour ==
== Behaviour ==
Characteristically shallow water, schooling fish (especially as juveniles), sweepers are [[nocturnal]] and seek shelter under ledges or in the caves, nooks and crannies of [[reef]]s or eroded, rocky shorelines during the day. They are often found sharing these hiding places with [[cardinalfish]]es and [[bigeye]]s, fellow nightowls. At night, sweepers forage for [[zooplankton]], their primary food items.
Characteristically shallow water, schooling fish (especially as juveniles), sweepers are [[nocturnal]] and seek shelter under ledges or in the caves, nooks and crannies of [[reef]]s or eroded, rocky shorelines during the day. They are often found sharing these hiding places with [[cardinalfish]]es and [[bigeye]]s, fellow nightowls. At night, sweepers forage for [[zooplankton]], their primary food items.


At least one species, the [[Small-scale Bullseye]] (''Pempheris compressa'') of [[Australia]], is known to enter coastal [[estuary|estuaries]] whilst young.
At least one species, the [[small-scale bullseye]] (''Pempheris compressa'') of [[Australia]], is known to enter coastal [[estuary|estuaries]] whilst young.


== Species ==
== Species ==

Revision as of 07:59, 2 June 2006

In football (soccer), "sweeper" is a defensive position. For more details, see libero.

Sweepers
Glassy Sweepers
Scientific classification
Kingdom:
Phylum:
Class:
Order:
Family:
Pempheridae
Genera

Parapriacanthus
Pempheris
See text for species.

Sweepers are small, tropical marine (occasionally brackish) perciform fish of the family Pempheridae. Found in the western Atlantic Ocean and Indo-Pacific region, the family contains approximately 26 species in two genera. One species (Pempheris xanthoptera ) is the target of subsistence fisheries in Japan, where the fish is much enjoyed for its taste. Sweepers are occasionally kept in the marine aquarium.

Physical description

Deeply keeled, compressed bodies and large eyes typify sweepers, their form somehwat like hatchetfish; both cycloid and ctenoid scales may be present. The small, short dorsal fin begins before the body's midpoint and may have 4-7 spines; the anal fin is extensive and usually has 3 spines. The mouth is subterminal and strongly oblique. Species of the genus Parapriacanthus have much more cylindrical bodies.

Some species possess photophores. All but the curved sweeper (Pempheris poeyi) possess a gas bladder. The largest species is the common bullseye (Pempheris multiradiata) at 28 centimetres in length; most other species measure 16 centimetres or less. Coloration is relatively subdued.

Behaviour

Characteristically shallow water, schooling fish (especially as juveniles), sweepers are nocturnal and seek shelter under ledges or in the caves, nooks and crannies of reefs or eroded, rocky shorelines during the day. They are often found sharing these hiding places with cardinalfishes and bigeyes, fellow nightowls. At night, sweepers forage for zooplankton, their primary food items.

At least one species, the small-scale bullseye (Pempheris compressa) of Australia, is known to enter coastal estuaries whilst young.

Species

There are 26 species in two genera:

Reference

  • Froese, Rainer; Pauly, Daniel (eds.). "Family Pempheridae". FishBase. November 2005 version.