Entosphenus minimus

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Entosphenus minimus
Systematics
Superclass : Round mouths (Cyclostomata)
Class : Petromyzontida
Order : Lampreys (petromyzontiformes)
Family : Petromyzontidae
Genre : Entosphenus
Type : Entosphenus minimus
Scientific name
Entosphenus minimus
( Bond & Kan , 1973)

Miller Lake Lamprey (Syn .: Lampetra minima , English common name : Miller Lake Lamprey ) is a Neunaugenart which is endemic in some outflows of Miller Lakes in Klamath County in the US state of Oregon found. It used to be at home in Miller Lake; there it wasdeliberately exterminatedin 1958 through the use of pesticides .

description

Entosphenus minimus is the smallest lamprey species with a length of 72 to 129 millimeters. The sucking mouth is equipped with thirteen to seventeen horn teeth. The core muscles are usually made up of 60 to 65 muscle sections.

Way of life

The eyeless and toothless Querder (larvae) stay in the soft sediment of the water bed and filter detritus and plankton from the water flowing by. After about five years they metamorphose and live parasitically as adults by suckling the blood of living fish.

status

Distribution area of Entosphenus minimus .
Miller Lake is located north-northeast of Crater Lake, here just outside the map section (upper edge).

Entosphenus minimus was thought to be extinct or lost between 1958 and 1992. Since the lampreys parasitized the brood (finger-length fry) of trout , they were viewed by fish farmers at Miller Lake as a plague and fought with pesticides such as toxaphene . At first it was probably not known that it was a unique species of lampreys that only occurs here. It was then long assumed that the only population in Miller Lake was found and wiped out by the pesticides. In 1992, however, an adult specimen of the species was rediscovered in the upper reaches of the Williamson River . Further searches in the 1990s revealed that the lamprey populations in Miller Creek , Jack Creek, and Sycan River also belong to the species Entosphenus minimus .

After the rediscovery formerly classified as "extinct" kind of was IUCN first in the Red List category "insufficient data" ( data deficient ) and in 2013 in the category "endangered" ( vulnerable provided).

Sources and further information

literature

  • Kan, TT & CE Bond: Notes on the biology of the Miller Lake lamprey LAMPETRA (ENTOSPHENUS) MINIMA . Northwest Science 55 (1981): 70-74.
  • David Stephen Lee et al .: Atlas of North American Freshwater Fishes . North Carolina State Museum of Natural History, Raleigh 1980, ISBN 0-917134-03-6 .
  • Lawrence M. Page & Brooks M. Burr: Peterson Field Guide Series - A Field Guide to Freshwater Fishes: North America North of Mexico . Houghton Mifflin Company, Boston, New York 1991, ISBN 0-395-91091-9 .

Web links