Gravenche
| Gravenche | ||||||||||||
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Gravenche ( Coregonus hiemalis ) |
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| Scientific name | ||||||||||||
| Coregonus hiemalis | ||||||||||||
| Jurine , 1825 |
The Gravenche ( Coregonus hiemalis ), also known locally as Kleine Fera or Kilch , is a freshwater fish from Lake Geneva that is believed to be extinct . The name Kilch is not only used for this species, but for several related taxa in the foothills of the Alps.
Systematics
The taxonomic status of the Gravenche is controversial as there are no preserved specimens in museums. In 1959 it was considered by Emile Dottrens as a subspecies of the lavaret ( Coregonus lavaretus ). However, other experts, including Maurice Kottelat and Jörg Freyhof , consider Coregonus hiemalis to be an endemic , independent species in Lake Geneva .
description
The gravenche was similar to the gang fish . They reached a total length of 25 to 32 centimeters. The eye diameter was 18 to 22 percent of the head length. There were 25 to 33 gill spines. The back was arched. The dorsal head profile and muzzle were rounded. Its head was thicker and the fins were relatively longer than those of the Féra. Her caudal fin was cut less deeply.
Way of life
The Gravenche had a benthopelagic way of life, which means that they mostly stayed near the ground. It was found at great depths and fed on animal plankton. The spawning season was in mid-December.
distribution
The Gravenche is or was endemic to the deep water areas of Lake Geneva. Older literature references name the Ammersee , the Chiemsee and the Bodensee for Coregonus hiemalis . However, these relate more to the Ammersee kilch ( Coregonus bavaricus ), the Chiemsee kilch ( Coregonus sp. ) And the Bodensee kilch ( Coregonus gutturosus )
die out
Together with Féra ( Coregonus fera ), which is also considered to be extinct , the Gravenche was one of the most heavily caught food fish on Lake Geneva. Around 1890, the quota for these two species was 68% of all fish caught in Lake Geneva. Overfishing ensured that it was extremely rare as early as the 1920s and has not been detected since 1950.
literature
- Maurice Kottelat: European Freshwater Fishes. An heuristic checklist of the freshwater fishes of Europe (exclusive of former USSR), with an introduction for non-systematists and comments on nomenclature and conservation ; Biologia: Section Zoology vol. 52/5, Slovak Academic Press, Bratislava 1997, ISBN 80-85665-87-5
Web links
- Gravenche on Fishbase.org (English)
- Meyers Konversationslexikon - Renke
- Corégone féra (fr.)
- Coregonus hiemalis in the endangered Red List species the IUCN 2008. Posted by: Freyhof, J. & Kottelat, M., 2008. Accessed on 18 November, 2008.