Desmidiaceae

End view Staurastrum dilatatum (Ehrenberg,1838) Ralfs, 1848.The four-armed semi-cells are rotated 45 degrees with respect to each other.From freshwater aquaculture tub near Boise, Idaho December 2005. DIC.

Differential interference contrast.

Cosmarium, one of the many desmids - most of which have the appearance of mirror imaged cells joined together, but typically with only one nucleus. With cellulose cell wall, bright green chloroplasts. Differential interference contrast.

Micrasterias(mike-raz-tear-ee-ass) is a genus of unicellular algae in the family Desmidiaceae. The cells are flattened and disc-like. The cells of the genus Micrasterias are organized in two semi-cells that are mirror images of each other. The semicells have a distinctive shape with an intricate lobes and indentation. At the end of the lobes the cell wall may sometimes form notches or short spines. The nucleus is located in the centre between the semicells. Each semicell has a chloroplast with some pyrenoids. Usually found in oligotrophic, acid waters. This specimen was collected in a moor located in the Salzburger Land, Austria. Differential interference contrast.

Cosmarium pachydermum P. LUNDELL  The cells are up to 1.4 times longer than wide and coarsely elliptical in shape. The cell halves are semicircular. The central cuts are narrowly rounded on the inside and extend strongly to the outside. The cell wall is thick. Some areas are covered closely, others are covered loosely with standing pores. The vertex view is broadly elliptical.  Length 100 - 120 µm, width 70 - 90 µm. Occurrence: acidophilic alga, widely spread in sphagnum bogs  

The image shows the jelly envelope with symbiontic bacteria. Scale bar indicates 25 µm.  Sample from sphagnum pond situated in the northern alpine region of Austria near Salzburg. Images were taken using Zeiss Universal with Olympus C7070 CCD camera.

[taxonomy:genus=Pleurotaenium] Desmid green alga Date: 9 Sep 2011, originally collected mid-Aug Location: Freshwater fish pond in concrete tank, outside Life Science Lab 7. Walls were covered in filamentous cyanobacteria, and the bottom with fish waste. Water was mostly clear. Pipetted sample from floc at bottom of tube which has settled after > two weeks Microscope: Bright-field with closed condenser aperture. Camera: Nikon D7000 Collector: Brandon Seah Scale: 20830 pixels/mm = 20.8 pixels/µm (40x)

Melgar de Tera, Castille and Leon, Spain

Sobrado, Galicia, Spain

Rozas de Puerto Real, Comunidad de Madrid, Espaa

Galende, Castille and Leon, Spain

Galende, Castille and Leon, Spain

Ribadelago, Castille and Leon, Spain

Ribadelago de Franco, Castilla y Len, Espaa

Canencia, Comunidad de Madrid, Espaa

Soba, Cantabria, Spain

Castilla y Len, Espaa

Ribadelago de Franco, Castille and Leon, Spain

Neila, Castille and Leon, Spain

Ribadelago de Franco, Castille and Leon, Spain

Ribadelago de Franco, Castille and Leon, Spain

Seville, Andalusia, Spain

Galende, Castille and Leon, Spain

Canencia, Madrid, Spain