Gomphonema
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Gomphonema | ||||||||||||
Ehrenberg |
Gomphonema is a genus of diatoms (Bacillariophyta) with around 100 species in fresh water.
features
The representatives are single-celled diatoms that are mainly attached to simple or branched gelatinous stems. The cells have a two-counter shell, which is typical for diatoms. The shell is wedge-shaped when viewed from the side; when viewed from the shell, it consists of two different cell poles: the narrow foot pole is on the gelatinous stalk, the wider one is the head pole. Each cell contains a large, H-shaped plastid with a central pyrenoid . The plastid is colored golden brown by fucoxanthin , its lobes lie under the shells. Both shells have a clear, centrally located raphe . The cells are 8 to 130 micrometers long.
Asexual reproduction occurs through the typical dichotomy of diatoms. Sexual reproduction occurs through anisogamy , with two gametes being formed per cell . The cells then enlarge during the auxospore formation.
Occurrence
Gomphonema lives mainly attached to the substrate. They occur in stagnant or poorly flowing waters, regardless of the nutrient content.
supporting documents
- Karl-Heinz Linne von Berg, Michael Melkonian u. a .: The Kosmos algae guide. The most important freshwater algae under the microscope. Kosmos, Stuttgart 2004, ISBN 3-440-09719-6 , p. 218.