Hysterocarpus traskii
| Hysterocarpus traskii | ||||||||||||
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Young fish from the Russian River |
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| Systematics | ||||||||||||
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| Scientific name of the genus | ||||||||||||
| Hysterocarpus | ||||||||||||
| Gibbons , 1854 | ||||||||||||
| Scientific name of the species | ||||||||||||
| Hysterocarpus traskii | ||||||||||||
| Gibbons, 1854 | ||||||||||||
Hysterocarpus traskii is a freshwater fish from the surf perchfamily(Embiotocidae). He lives in Clear Lake , in the Sacramento River and in the San Joaquin River in California's Long Valley , as well as in the Russian River and in the Salinas River west of the California Coastal Mountains . Hysterocarpus traskii is the only species in the genus Hysterocarpus . The genus name is derived from the Greek “hystera” for uterus and refers to the viviparity of the species. The species epithet was given in honor of JB Trask, whocaughtthe type specimens and sent them to the American naturalist and ichthyologist William P. Gibbons .
features
Hysterocarpus traskii becomes 15 cm long. The species is high-backed and has a small, terminal mouth. Adults often have a pronounced hump between the head and dorsal fin. The coloring is variable. The back is usually dark, often with a purple or bluish tinge. The color of the underside can be whitish or yellowish. The flanks can be patterned or unbanded with narrow or wide transverse bands.
- Fins formula : dorsal XV – IXX / 9–15, anal III / 20–26, pectoral 17–19.
- Scale formula : SL 34–43.
Way of life
Hysterocarpus traskii lives above muddy or gravelly soils in lakes and the lower reaches of rivers and is mostly found under overhanging plants or between aquatic plants. The species rarely goes into brackish water . It feeds on zooplankton and hard-shelled, bottom-living invertebrates. Like all surfperch is Hysterocarpus traskii viviparous ( viviparous ). The males' sperm is transmitted through modified anal fin rays. The mating season extends from July to September. Depending on the size of the female, 22 to 83 fry are born from May to June.
literature
- Lawrence M. Page, Brooks M. Burr: A Field Guide to Freshwater Fishes: North America North of Mexico , Peterson Field Guides, ISBN 0-3959-1091-9
- Peter B. Moyle: Inland Fishes of California. University of California Press, 1976, ISBN 0-5200-2975-5
Web links
- Hysterocarpus traskii on Fishbase.org (English)
- Hysterocarpus traskii inthe IUCN Red List of Threatened Species 2013.2. Listed by: NatureServe, 2012. Retrieved January 12, 2014.