Chlorophyceae

Pediastrum solare.

Pediastrum trochiscus.

Pediastrum tetras.

Portrait of the hydrodictyacean, pediastrum tetras (Ehrenberg) Ralfs,1844.Collected from a freshwater pond near Boise, Idaho. July 2005. DIC.

Portrait of Vitreochlamys fluviatilis, formerly Sphaerellopsis fluviatilis. The genus name, Sphaerellopsis (Korchikoff, 1925) was preoccupied by an Ascomycete fungus. This fungus Sphaerellopsis filum (Cooke, 1883) is a hyperparasite of another fungus, willow rust (Melampsora). Batko renamed this volvocid flagellate genus Vitreochlamys. This genus is similar to Chlamydomonas (some consider it synonymous) but differs from it by having a protoplast and surrounding gelatinous sheath that are fusiform. There are two equal length flagella. The nucleus is central. There is a large cup-shaped chloroplast and a posterior pyrenoid. Two anterior contractile vacuoles are located near the flagellar bases. There is a small anterior stigma. From a freshwater pond near Boise, Idaho. Oblique illumination. 

Portrait (lateral view) of the chaetophoralean alga, Aphanochaete repens (Braun, 1849). A. repens is epiphytic on filamentous algae (in this case Oedegonium). The cells are cylindrical to cuboid, some bearing one long clear seta with a bulbous base. The cells arrange themselves in files with short branches along the long axis of their host algal filament. Collected from a freshwater pond near Boise, Idaho June 2004. DIC optics.

Portrait (lateral view) of the chaetophoralean alga, Aphanochaete repens (Braun, 1849). A. repens is epiphytic on filamentous algae (in this case Oedegonium). The cells are cylindrical to cuboid, some bearing one clear seta with a bulbous base. The cells arrange themselves in files with short branches along the long axis of their host algal filament. Collected from a freshwater pond near Boise, Idaho June 2004. DIC optics.

Portrait (lateral view) of the chaetophoralean alga, Aphanochaete polychaete (Fritsch, 1902). A. polychate is epiphytic on filamentous algae (in this case Oedegonium). The cells are cylindrical to cuboid, bearing more than one clear seta with a bulbous base (some cells here appear to have only one seta, the others being out of the focal plane of the image ). The multiple setae of A. polychaete differentiate it from A. repens which has only one seta per cell. The cells arrange themselves in files with short branches along the long axis of their host algal filament. Collected from a freshwater pond near Boise, Idaho June 2004. DIC optics.

Asterococcus (a-stir-owe-cock-us) superbus. The large round or ellipsoid cells of Asterococcus occur singly or in groups with up to 8 cells embedded in a well-developed mucilage envelope. Groups reach 180 microns in diameter. The gelatinous sheaths are normally colourless and in concentrically arranged layers. The sheaths may be coloured brown by iron hydroxide. The single chloroplast is star-shaped and the pyrenoids are arranged in the center of the cell. The nucleus is located in a gap between the strands of the chlororoplast, together with two contractile vacuoles. No eyespot. Common in freshwater ponds and lakes. This image is of a squashed colony of Asterococcus superbus. The concentrically arranged layers of the gelatinous sheaths are clearly visible. The cells measuring 22 - 26 microns in diameter. Differential interference contrast.

Portrait of the filamentous green alga, Chaetophora elegans (Roth; Agardh, 1812). Globular or lobulated colonies are embedded in a gelatinous matrix. The branching filaments terminate in tapered tips or long thin multicellular hair-like projections seen on the left in this image. The cells are cylindrical, containing a single parietal chloroplast and one to several pyrenoids. Branch filaments and axial filaments are similar in appearance. Collected from a freshwater pond near Boise, Idaho October 2004. DIC.

Detail of the filamentous green alga, Chaetophora elegans (Roth; Agardh, 1812). Globular or lobulated colonies are embedded in a gelatinous matrix. The branching filaments terminate in tapered tips or long thin multicellular hair-like projections. The cells are cylindrical, containing a single parietal chloroplast and one to several pyrenoids. Branch filaments and axial filaments are similar in appearance. Collected from a freshwater pond near Boise, Idaho October 2004. DIC.

Portrait of the planktonic chlorococcalean alga Golenkinia radiata (Chodat,1894) Korshikov,1953.Cells are solitary, spherical with multiple radiating fine spines at least 2-3 times cell width in length.There is a single cup-shaped chloroplast.Collected from a freshwater pond near Boise, Idaho. DIC.

Portrait of the planktonic chlorococcalean alga Golenkinia radiata (Chodat,1894) Korshikov,1953.Cells are solitary, spherical with multiple radiating fine spines at least 2-3 times cell width in length.The thin gelatinous sheath is seen in this image.There is a single cup-shaped chloroplast.The single pyrenoid is seen here.Collected from a freshwater pond near Boise, Idaho. DIC.

Portrait of the planktonic chlorococcalean alga Golenkinia radiata (Chodat,1894) Korshikov,1953.Cells are solitary, spherical with multiple radiating fine spines at least 2-3 times cell width in length.There is a single cup-shaped chloroplast.Collected from a freshwater pond near Boise, Idaho. Phase contrast.

In vivo portrait of the volvocid flagellate,  Volvulina steinii Playfair,1915. Collected from a temporary rainwater puddle on a grass lawn in Boise, Idaho 43°36'49.03"" N 116° 13' 23.77"" W elev. 2674 ft.March 2006.Brightfield.

Portartit of the volvocid flagellate, Volvulina steinii Playfair,1915. The cells are hemispherical with the flattened face of each toward the exterior in contact with the thin investing gelatinous envelope.The inner limit of the envelope is visible here. the thickness of the investing layer of the gelatinous envelope is indicated here by debris adhering to its exterior surface.Each of the 16 cells in the colony bears two equal-length flagella (seen here in the cell at 12 o'clock). Only cells at the ""anterior"" end of the colony have eyespots. each cell has two contractile vacuoles (seen here in the cell at 12 o'clock.Collected from a temporary rainwater puddle on a grass lawn in Boise, Idaho  In vivo portrait of the volvocid flagellate,   43°36'49.03"" N 116° 13' 23.77"" W elev. 2674 ft. elev. 2674 ft.  March 2006.  DIC.

In vivo portartit of slightly compressed volvocid flagellate, Volvulina steinii Playfair,1915 showing the two contractile vacuoles. The single nucleus of several cells is visible. Only the ""anterior"" cells of the colony have red eyespots. Collected from a temporary rainwater puddle on a grass lawn in Boise, Idaho.  43°36'49.03"" N 116° 13' 23.77"" W elev. 2674 ft. March 2006.  DIC.    

In vivo surface view of the volvocid flagellate, Volvulina steinii Playfair,1915. Collected from a temporary rainwater puddle on a grass lawn in Boise, Idaho 43° 36' 49.03"" N 116° 13' 23.77"" W elev. 2674 ft. March 2006. DIC.

Treubaria setigera is relatively rare in Lake Kinneret. This specimen was collected at the shore by the Kinneret Limnological Laboratory in March 2006.

Close-up view of Asterococcus limneticus. In the center of the cell we see a pyrenoid amidst the stellate chloroplast. In addition, the right cell shows the nucleus (1) and the two contractile vacuoles (2).   Sample from sphagnum pond Dosenmoor near Neumuenster (Schleswig-Holstein, Germany). Images were taken using Zeiss Axioplan with Canon 600D CCD camera.  Image under Creative Commons License V 3.0 (CC BY-NC-SA).

Scenedesmus flexuosus(Lemmermann) Ahlstrom. DIC.