Caspine lamprey

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Caspine lamprey
Systematics
Superclass : Round mouths (Cyclostomata)
Class : Petromyzontida
Order : Lampreys (petromyzontiformes)
Family : Petromyzontidae
Genre : Caspiomyzon
Type : Caspine lamprey
Scientific name of the  genus
Caspiomyzon
Berg , 1906
Scientific name of the  species
Caspiomyzon wagneri
( Kessler , 1870)

The Caspian lamprey ( Caspiomyzon wagneri ) is the only member of the genus Caspiomyzon from the order of lamprey (Petromyzontiformes).

features

The Caspine lamprey has an eel-like, scaly body. Like all lampreys, it has a cartilaginous skeleton, no vertebrae and no pair of fins. Its maxillary plate is narrow and has only one blunt tooth. On the other hand, there are 5 teeth on the lower jaw plate, of which the two outer ones sometimes have 2 cusps. The inner area of ​​the mouth disc is covered with blunt horn teeth, while the outer area has weak, rounded horn teeth arranged in inclined arches. The front tongue plate has a row of teeth of the same size on its front edge, there is no central depression of the tongue plate. The dorsal fins of the adult animals are, depending on the stage of maturity, separated by a wide space or are in contact with each other. The second dorsal fin is connected to the caudal fin.

The back of the species is light greenish to dark olive in color, marbling or dark spots are not present. The flanks and the belly are light and have a silvery sheen. The caspine lamprey usually reaches a length of 20 to 40 cm, specimens up to 55 cm are rare and weighs 200 g.

distribution

The Caspine lamprey is endemic to the Caspian Sea as well as flowing rivers such as the Volga (including its tributaries Kama and Oka ), Urals , Terek, and Kura .

Way of life

The caspine lamprey is a non-parasitic species that ascends in large flocks in the rivers from October to December. From this point on, the animals stop eating. After the hibernation, the species spawns from March to May. The females spawn between 20,000 and 36,000 eggs in nest pits at suitable sandy and gravelly spots in the river bed, depending on their size. After spawning, the animals die.

swell

literature

  • Gunter Steinbach (ed.): Freshwater fish (The colored nature guides). Mosaik Verlag, Munich 1984.

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