-
Phase contrast image of Stephanopyxis sp. (after being cleared with bleach) isolated from the waters near Martha's Vineyard . Photo courtesy of Andrew Schurko.
-
Stephanopyxis (steff-ann-o-pick-sus) palmeriana, a filament-forming centric diatom in which the cells are linked together by processes arising from the valves. The valves are the parts of the shell or frustule at the ends of each cell, and are more sculpted than the girdle bands, and so refract more light appearing brighter in this image, which includes many resting cells. The golden colour from plastids which contain chlorophylls a and c, but more significantly with carotenoids such as fucoxanthin which provide the distinctive colour. Dark ground illumination.
data on this strain.
-
-
Grove, O, Galicia, Spain
-
Aulacoseira granulata.Scale bar indicates 25 m. The specimen was gathered in the wetlands of Oderbruch (Oder valley 100 km north east of Berlin). The image was built up using several photomicrographic frames with manual stacking technique. Images were taken using Zeiss Universal with Olympus C7070 CCD camera.For more look at
www.protisten.de/english/gallery_main/gallery_main.htmlFor high-resolution images please ask postmaster@protisten.de.
-
-
Aulacoseira (formerly Melosira) granulata (Bacillariophyta, Centrales) is one of the most common diatoms of Lake Kinneret, and certainly the major phytoplankton biomass contributor in winter (Dec â Feb), when the water column is homothermal. Typically, it occupies the entire 43 m water column. At the end of the winter bloom in early March the filaments sink and remain in the sediments in a dormant form with compressed chloroplasts till they are resuspended when the lake destratifies the following fall. It is a relatively large filamentous diatom, with cell diameter of 9 â 15 μm (median: 12.4 μm), cell height of 27-37 μm (median: 31 μm), and mean cell volume of 3700 μm3. The Kinneret Aulacoseira granulata filaments are straight, typically with 8 - 24 cells per filament. The picture shows the typical equal length marginal spines at the perimeter of the end-cell, these are âlinking spinesâ which hold adjacent cells together. The chloroplasts fill the entire cells. This specimen was sampled from the shore of the lake in June 2006. Aulacoseira granulata is a widespread centric diatom in the phytoplankton of lakes, reservoirs and rivers world-wide but particularly in African lakes and rivers, including the Nile River, L Naivasha, Kenya. It is typical of carbonate-rich, moderately eutrophic to eutrophic waters. It is used as indicator species of water with relatively low concentrations of salts, pH less than 9, and high silica concentrations.
-
SEM image of a Stephanopyxis sp. valve. Original sample isolated from the waters near Martha's Vineyard as part of the 2005 ATOL Protistology Workshop. Image courtesy of Shauna Murray and Andrew Schurko.
-
Stephanopyxis (steff-ann-o-pick-sus) palmeriana, a filament-forming centric diatom in which the cells are linked together by processes arising from the valves. The valves are the hemispherical regions at the ends of the cell, and have a hexagonal texture, and the girdle is the region in the middle. The golden colour from plastids which contain chlorophylls a and c, but more significantly with carotenoids such as fucoxanthin which provide the distinctive colour. Differential interference microscopy.
data on this strain.
-
Valvar view. Scale bar indicates 25 µm. Sample from North Sea near Heligoland (spring diatom bloom). The image was built up using several photomicrographic frames with manual stacking technique. Images were taken using Zeiss Universal with Olympus C7070 CCD camera.
-
Talamanca, Catalonia, Spain
-
Filaments of different thickness typical of the winter (Jan-Feb) A. granulata bloom development season in Lake Kinneret
-
SEM image showing the valves of Stephanopyxis sp. Original sample isolated from the waters near Martha's Vineyard as part of the 2005 ATOL Protistology Workshop. SEM image courtesy of Shauna Murray and Andrew Schurko.
-
Stephanopyxis (steff-ann-o-pick-sus) palmeriana, a filament-forming centric diatom in which the cells are linked together by processes arising from the valves - as shown here. The golden plastids contain chlorophylls a and c, but more significantly with carotenoids such as fucoxanthin which provide the distinctive colour. Differential interference microscopy.
data on this strain.
-
Scanning electron microscope image of valve. The organism is tentatively identified as C. radiatus. Sample taken from the water column off Martha's Vineyard, Massachusetts. Image by Charley O'Kelly and Shauna Murray.
-
Sogo, Castille and Leon, Spain
-
Centric diatom, seen from valve view. This is an empty frustule of a large marine species. The pattern of pores in the frustule is used in identification. Marine. Phase contrast.
-
Stephanopyxis (steff-ann-o-pick-sus) palmeriana, a filament-forming centric diatom in which the cells are linked together by processes arising from the valves. The valves are the hemispherical regions at the ends of the cell, and have a hexagonal texture. Differential interference microscopy.
data on this strain.
-
Scanning electron micrograph showing detail of the frustule of this diatom. The larger depressions are called areolae, and perforated region is called the cribrum, within which each perforation is referred to as a cribellum. The same term probably also refers to the perforations in the margins of the areolae. The species is probably C. radiatus. Sample from the water column off Martha's Vineyard. Images by Charley O'Kelly and Shauna Murray.
-
Aguilar Del Rio Alhama, La Rioja, Spain
-
Coscinodiscus (coss-co-no-disc-us) a centric diatom, seen from valve view. This is an empty frustule of a large marine species. The pattern of pores in the frustule is used in identification. Marine. Phase contrast.
-
This species is easily identified by its hexagonal central area and its division into usually six sectors with alternating raised and depressed areas. It is a cosmopolitan species andcan be abundant in cold to temperate coastal waters
-
This species has a very fine aerolation. It can be distinguished from other species by the central hyaline area and the hyaline lines radiating from it between the areolae. It also has a distinctive shape in girdle view. The valve is very high (often higher than wide) and the valve margin appears to undulate slightly.
-
Aguilar del Ro Alhama, La Rioja, Espaa