Cosmarium

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Cosmarium
Cosmarium ochthodes (size: 62 µm × 47 µm)

Cosmarium ochthodes (size: 62 µm × 47 µm)

Systematics
without rank: Chloroplastida
without rank: Charophyta
Class : Ornamental algae (Zygnemophyceae)
Order : Ornamental algae (Desmidiales)
Family : Desmidiaceae
Genre : Cosmarium
Scientific name
Cosmarium
Ralfs

Cosmarium (of gr. Kosmarion = "small jewelry") is the name of a relative with about 1,000 representatives described species-rich genus of ornamental algae . The genus belongs to the Desmidiaceae family.

description

Cosmarien consist of two half-cells, usually 5 to 50 µm in size, which are connected by a so-called isthmus , which contains the cell nucleus . In contrast to the similar genus Micrasterias , the often kidney-shaped half-cells are not incised or lobed. However, the cell walls of numerous species are sculptured in a characteristic way, so that empty cell walls of dead Cosmaria are used as identifying features .

In contrast to the cell walls of the similar genera Staurodesmus , Staurastrum and Xanthidium, they never have spines. In addition to these features, the cell size, width and their ratio serve as important identifying features. Cosmarien usually occur in relatively clean, soft water and therefore belong e.g. B. on the flora of the moors . Species such as Cosmarium cucurbita and Cosmarium pygmaeum are considered sphagnophilic . In addition to species that are closely tied to certain living conditions , there are others that are more common and z. B. colonize small ponds or damp earth, gravel and sand places. Since biotopes with clean, soft water have become rarer, numerous Cosmarium species are now endangered species (see Red List of Endangered Species ).

Representative

  • Cosmarium vexatum

  • Cosmarium quadratum (68 × 37 µm)

  • Cosmarium pseudamoenum (48 × 25 µm)

literature

  • Urania plant kingdom . Volume 2: Moose, Farne, Nacktsamer, 1st edition 1992, Urania-Verlag, Leipzig 1992, ISBN 3-332-00495-6

Web links

Commons : Cosmarium  - collection of images, videos and audio files