sweeper

Sweepers
Glassy Sweepers
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Actinopterygii Order: Perciformes 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 somewhat 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

Red Sea dwarf sweepers (Parapriacanthus guentheri)

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:

• Genus Parapriacanthus
  • Parapriacanthus dispar (Herre, 1935).
  • Slender bullseye, Parapriacanthus elongatus (McCulloch, 1911).
  • Parapriacanthus marei Fourmanoir, 1971.
  • Pigmy sweeper, Parapriacanthus ransonneti Steindachner, 1870.
• Genus Pempheris
  • New Zealand bigeye, Pempheris adspersa Griffin, 1927.
  • Dusky sweeper, Pempheris adusta Bleeker, 1877.
  • Black-tipped bullseye, Pempheris affinis McCulloch, 1911.
  • Bronze sweeper, Pempheris analis Waite, 1910.
  • Small-scale bullseye, Pempheris compressa (White, 1790).
  • Pempheris japonica Döderlein, 1883.
  • Klunzinger's bullseye, Pempheris klunzingeri McCulloch, 1911.
  • Black-edged sweeper, Pempheris mangula Cuvier, 1829.
  • Pempheris molucca Cuvier, 1829.
  • Common bullseye, Pempheris multiradiata Klunzinger, 1880.
  • Pempheris nyctereutes Jordan & Evermann, 1902.
  • Pempheris ornata Mooi & Jubb, 1996.
  • Pempheris otaitensis Cuvier, 1831.
  • Silver sweeper, Pempheris oualensis Cuvier, 1831.
  • Curved sweeper, Pempheris poeyi Bean, 1885.
  • Pempheris rapa Mooi, 1998.
  • Glassy sweeper, Pempheris schomburgkii Müller & Troschel, 1848.
  • Pempheris schreineri Miranda-Ribeiro, 1915.
  • Black-stripe sweeper, Pempheris schwenkii Bleeker, 1855.
  • Vanikoro sweeper, Pempheris vanicolensis Cuvier, 1831.
  • Pempheris xanthoptera Tominaga, 1963.
  • Pempheris ypsilychnus Mooi & Jubb, 1996.

References

• "Pempheridae". FishBase. Ed. Rainer Froese and Daniel Pauly. November 2005 version. N.p.: FishBase, 2005.