Small dogfish
| Small dogfish | ||||||||||||
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Small dogfish ( Umbra pygmaea ) |
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| Scientific name | ||||||||||||
| Umbra pygmaea | ||||||||||||
| ( DeKay , 1842) |
The small dogfish ( Umbra pygmaea ) is a small freshwater fish from the order of the pike-like (Esociformes). It lives in eastern North America from southwest New York (including Long Island ) to the St. Johns River in Florida and west to the Aucilla River in Florida and Georgia . It has been introduced locally in Western and Central Europe (Central France, Northern Germany).
features
The small dogfish has a stocky, elongated body that is only slightly flattened on the sides and is 11.5 cm (males) to 15 cm (females) long. The length of the mouth corresponds to the diameter of the eye. The gill rays are short and numerous. The dorsal fin sits far back, its upper edge is rounded. The anal and caudal fin are also rounded. The attachment of the pelvic fin is well in front of the beginning of the dorsal fin. The small dogfish has a dark green back and yellow-green sides, on which 10 to 12 narrow, dark to brownish-green longitudinal stripes can be seen. There is a dark transverse bar on the tail fin stalk.
- Fin formula : dorsal 14–15, anal 8–11, caudal 18–20.
- Scale formula : LR 35–37.
Way of life
The fish live in swamps, in quiet areas of streams and small rivers over sandy and muddy bottoms, mostly in dense vegetation. They tolerate a low oxygen content in the water, high water temperatures and a pH value of 4.0 to 7.0. Young fish often live in small groups of 10 to 12 animals. The small dogfish feed on small invertebrates , e.g. B. worms, small molluscs , hoppers , water fleas and insects. It spawns from March to April. The female presumably takes care of the brood and guards the eggs deposited in a prepared nest. The fry hatch after five to ten days. They do not become sexually mature until they are two years old.
literature
- Fritz Terofal: Steinbach's natural guide, freshwater fish. Ulmer, Stuttgart 2003, ISBN 3-80014-296-1
Web links
- Small dogfish on Fishbase.org (English)
- Umbra pygmaea inthe IUCN 2013 Red List of Threatened Species . Listed by: NatureServe, 2012. Retrieved November 25, 2013.