Baikal pellets

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The division of living beings into systematics is a continuous subject of research. Different systematic classifications exist side by side and one after the other. The taxon treated here has become obsolete due to new research or is not part of the group systematics presented in the German-language Wikipedia.

The Baikal pellets (Cottocomephoridae Berg , 1907) are a no longer generally recognized family of small freshwater fish that occur in the Siberian Lake Baikal , its tributaries and some other Siberian rivers ( Angara , Irkut , Selenga ).

features

Baikal globules are 14 to 24 centimeters long. They have a thick, broad head with a large mouth and a body that tapers backwards to the caudal fin. The pectoral fins are large, the pelvic fins are far forward below the pectoral fins. The hard-rayed and the longer, soft-rayed part of the dorsal fin are clearly separated from each other by an indentation. Baikal pellets are usually camouflaged gray or blackish in color. In species that live at greater depths, reddish, brown, brownish-yellow to pale yellow tones with light spots on the upper side of the body dominate. The size of the eyes also depends on the depth of the habitat. Deep sea species have large eyes and a well-developed lateral line organ . Cottocomephoridae feed mainly on amphipods (amphipods), are demersal (bottom to falling eggs) and are themselves an important food for larger fish of Lake Baikal and the Baikal seal . Some Baikal groups are pelagic . All Baikal pellets lack the postcleithra (a bone in the shoulder girdle).

Systematics

Phylogenetically are the cottocomephoridae, as well as in deeper layers of Baikal endemic living abyssocottidae (Abyssocottidae) and comephorus (Comephoridae) within the genus Cottus from the family of bullhead (Cottidae). The American ichthyologist Joseph S. Nelson therefore no longer lists the family in his standard work on the fish system, Fishes of the World, and puts the genera and species of the Baikal group into the bullheads.

Genera and species

There are nine species in four genera:

literature

Individual evidence

  1. Leocottus kesslerii on Fishbase.org (English)
  2. Batrachocottus nikolskii on Fishbase.org (English)
  3. Andrew P. Kinziger, Robert M. Wood, David A. Neely: Molecular Systematics of the Genus Cottus (Scorpaeniformes: Cottidae). Copeia , 2005 (2): 303-311. 2005. doi : 10.1643 / CI-03-290R1
  4. Leo Smith, Ward C. Wheeler: Polyphyly of the mail-cheeked fishes (Teleostei: Scorpaeniformes): evidence from mitochondrial and nuclear sequence data , Molecular Phylogenetics and Evolution Volume 32, Issue 2, August 2004, Pages 627-646 doi : 10.1016 /j.ympev.2004.02.006

Web links