The western pygmy perch (''Nannoperca vittata'') is a species of temperate perch endemic to southwestern Australia.

Description

The Western pygmy perch is a small fish with an olive, brown and green mottled body with tow orange stripes along the flanks. In the breeding season the males develop brighter colouration with golden mottling along the flanks, an reddish-orange abdomen and the fins darken. The females develop a bluish colour when breeding. It can reach TL.

Distribution

The Western pygmy perch is endemic to the south-western coastal drainages of Western Australia. Its range extends from the

Waychinicup River The Waychinicup River is located in the Great Southern region of Western Australia. The headwaters of the river are located near the town of Manypeaks along the South Coast Highway, with an elevation of approximately above sea level and flows ...

east of Albany to the

Arrowsmith River The Arrowsmith River lies within the Mid West region of Western Australia. The explorer George Grey found the river on 11 April 1839, on his second expedition along the west coast. He named it after the distinguished English cartographer Joh ...

north of Perth. It occurs in the majority of the river drainages within its range, as well as in lakes near the south coast.

Habitat and biology

The Western pygmy perch is found predominantly in lakes, streams, and swamps, and can withstand a degree of brackishness. They have a preference for living among vegetation in the shallows around the water perimeter, and acclimatise readily to a range of water temperatures from almost 0 to 25 °C. Pygmy perch are egg layers. They produce eggs singly, laying 12 to 15 over a period of up to three hours. During the breeding season (July to November), both sexes become noticeably more colorful. The eggs measure around 1.2 mm and are slightly adhesive, which allows them to cling to submerged plants, rocks, or debris. Spawning usually occurs in the latter part of the morning. Hatching occurs after around three days from laying. The 3-mm larvae look quite different from juveniles of the species and have no mouth for several days, but are recognizably perch-like after around 27 to 30 days. This species is mainly carnivorous, they eat various

diptera Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advanced ...

n larvae, including mosquitos, ostracods, and

copepods Copepods (; meaning "oar-feet") are a group of small crustaceans found in nearly every freshwater and saltwater habitat. Some species are planktonic (inhabiting sea waters), some are benthic (living on the ocean floor), a number of species have p ...

, and small quantities of

algae Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular mic ...

, and are adept at taking mosquitoes from the surface of the water. They attain sexual maturity at one year old, and can live as long as 5 years.

Uses

Pygmy perch may be safely kept in an aquarium along with tropical fish. They are considered safe with tadpoles, so are used in frog ponds to control mosquito larvae.

References

{{Taxonbar, from=Q6431678

western pygmy perch The western pygmy perch (''Nannoperca vittata'') is a species of temperate perch endemism, endemic to Southwest Australia, southwestern Australia. Description The Western pygmy perch is a small fish with an olive, brown and green mottled body wi ...

Freshwater fish of Western Australia

Taxa named by François-Louis Laporte, comte de Castelnau Endemic fauna of Southwest Australia