Tench - WikiHQ

The tench or doctor fish (Tinca tinca) is a fresh- and brackish-water fish of the order Cypriniformes found throughout Eurasia from Western Europe including Britain and Ireland east into Asia as far as the Ob and Yenisei Rivers. It is also found in Lake Baikal. It normally inhabits slow-moving freshwater habitats, particularly lakes and lowland rivers.

Taxonomy

The tench was first formally described in as Cyprinus tinca by Carl Linnaeus in 1758 in the 10th edition of Systema Naturae with its type locality given as "European lakes". In 1764 François Alexandre Pierre de Garsault proposed the new monospecific genus Tinca, with Cyprinus tinca as the type species by absolute tautonymy. while other authorities classified both these genera in the subfamily Leuciscinae with other Eurasian minnows, but more recent phylogenetic studies have supported it belonging to its own family Tincidae. The Tincidae was first proposed as a name in 1878 by David Starr Jordan.

Evolution

thumb|left|Fossil specimen of [[Tinca furcata]]The Tincidae have a rather comprehensive fossil record in Europe. They first appear during the Late Oligocene with the fossil genera †Tarsichthys Troschel, 1854 and the potentially synonymous †Palaeotinca Obrhelová, 1969.

For the extant Tinca, the fossil species †Tinca furcata Agassiz, 1832 is known from Late Miocene-aged deposits near Ohningen, and the contemporaneous †Tinca micropygoptera Agassiz, 1839 is known from near Steinheim am Albuch. The extinct species †Tinca sayanica Sytchevskaya, 1989 is known from the Late Miocene or Early Pliocene of Mongolia. †Tinca pliocenica Gaudant, 1998 is known from the Pliocene of Germany. From the Late Miocene onwards, Tinca remains are overall widespread in freshwater deposits of Europe and West Asia, although they are usually not assignable to species. The earliest remains of the modern Tinca tinca are from the late Pliocene of the Netherlands.

Ecology

thumb|On exhibition, in [[Prague]]The tench is most often found in still waters with a clay or muddy substrate and abundant vegetation. This species is rare in clear waters across stony substrate, and is absent altogether from fast-flowing streams. It tolerates water with a low oxygen concentration, and snails and pea clams in well-vegetated waters.

Breeding takes place in shallow water usually among aquatic plants where the sticky green eggs can be deposited. Growth is rapid, and fish may reach a weight of within the first year.

Morphology

Tench have a stocky, carp-like shape and olive-green skin, darker above and almost golden below. The tail fin is square in shape. The other fins are distinctly rounded in shape.

left|thumb|In [[England]]

Maximum size is , though most specimens are much smaller. A record fish caught in 2001 in England had a weight of . The eyes are small and red-orange in colour. and noticeable muscles around the base of these fins generally absent in females. Males also possess a very thick and flattened outer ray to the ventral fins.

Angling

Large tench may be found in gravel pits or deep, slow-moving waters with a clay or silt bottom and copious aquatic vegetation. The best methods and bait to catch tench are float fishing and ledgering with a swim feeder using maggots, sweetcorn, pellets, bread, and worms. Fish over in weight are very strong fighters when caught on a rod.