Chlorophyceae

This is an un-named species of Dunaliella, a green alga and member of the phytoplankton that is often associated with hypersaline conditions. The chloroplast is bowl-shaped and fills the base of the cell. There is a yellowy eyespot to the left side of the plastid in this image. The nucleus with nucleolus lies near the front of the cell. There are two equally long flagella which beat in a breast-stroke motion. Phase contrast micrograph. 

This image is of a sea-water lagoon in Western Australia. The water is red because of the very large numbers of Dunaliella salina, a green alga that is commercially harvested for carotenes as food additives and coloring agents.

Polytomella (paul-ee-toe-mell-a) is one of a small number of green (Viridaeplantae) algal genera which lack plastids. There are four flagella inserting in a square pattern - and only two opposed flagella can be seen in this image. The flagella insert in small dimples at the anterior end of the cell. Often found in habitats rich in organic matter and low in oxygen. Phase contrast.

This flagellated protozoa was observed from a perchlorate treating laboratory scale anaerobic bioreactor (ORP~ -200 mV) fed with acetate as substrate. It was characterized by a pair of anterior flagella, tailing body and intracellular starch granules. Krishnakumar B and Anupama V.N. of NIIST (CSIR) are involved in the bioreactor study. The phase contrast image shows cells with intracellular starch granules and the same released to the medium.

Gonium pectorale, a common colonial volvocid flagellate. Colonies usually consist of 16 cells (twelve peripheral and four central) in a plate-like arrangement of one layer. An extracellular matrix that is not easily seen connects cells. Cells have a cup-shaped chloroplast with a small anterior stigma. Lateral view of colony. From freshwater pond near Boise, Idaho. Phase contrast.

Gonium pectorale, a common colonial volvocid flagellate. Colonies usually consist of 16 cells (twelve peripheral and four central) in a plate-like arrangement of one layer. An extracellular matrix that is not easily seen connects cells. Cells have a cup-shaped chloroplast with a small anterior stigma. Anteroposterior view of colony. From freshwater pond near Boise, Idaho. Brightfield illumination.

Lateral view of Gonium pectorale (Muller), a common colonial volvocid flagellate. Colonies usually consist of 16 biflagellate cells (twelve peripheral and four central) in a plate-like arrangement of one layer. An extracellular matrix that is not easily seen connects cells. Cells have a cup-shaped chloroplast with a small anterior stigma. Lateral view of colony. Collected from a freshwater pond near Boise, Idaho. Brightfield

Anterior apical view of Gonium pectorale (Muller), a common colonial volvocid flagellate. Colonies usually consist of 16 biflagellate cells (twelve peripheral and four central) in a plate-like arrangement of one layer. An extracellular matrix (not easily seen without phase or differential intereference contrast techniques) connects cells. Cells have a cup-shaped chloroplast with a small anterior stigma. Collected from a freshwater pond near Boise, Idaho. DIC.

Anterior apical view of Gonium pectorale (Muller), a common colonial volvocid flagellate. Colonies usually consist of 16 biflagellate cells (twelve peripheral and four central) in a plate-like arrangement of one layer. An extracellular matrix that is not easily seen connects cells. Cells have a cup-shaped chloroplast with a small anterior stigma. Lateral view of colony. Collected from a freshwater pond near Boise, Idaho. DIC.

Tetrabaena socialis, a colonial volvocid flagellate. T. socialis was formerly known as Gonium sociale until the monospecific genus Tetrabaena was erected (Nozaki,H. and Itoh, M. J. Phycol. 30:353-365, 1994).The colonies are plate-shaped with four cells all oriented in the same direction. Extracellular matrix joining adjacent cells can be seen. The gelatinous envelope surrounding the whole colony is not seen in these images. The ovoid cells have two equal-length flagella, a small eyespot, large cup-shaped chloroplast and posterior round pyrenoid. From freshwater pond near Boise, Idaho. Oblique illumination.

Tetrabaena, a green alga (Chlorophyta) in which four cells form a colony within a delicate mucoid matrix. Each cell with two apical flagella. This image shows an eyespot in one cell.

Tetrabaena, a green alga (Chlorophyta) in which four cells form a colony within a delicate mucoid matrix. Each cell with two apical flagella that beat with a breast-stroke pattern.

Eudorina (you-door-ine-a) is a colonial volvocid - motile green alga. In this case 16 cells are embedded in a sphere of common mucus. Each individual cell has two flagella, and a cup-shaped chloroplast - a bit like a Chlamydomonas cell. There are a number of related genera which form colonies using mucus as a common matrix, but they differ in the numbers of cells involved, how tightly packed they are, and the shape of the colony. Differential interference contrast.

Eudorina (you-door-ine-a) is a colonial volvocid - motile green alga. In this case 16 cells are embedded in a sphere of common mucus. Each individual cell has two flagella, and a cup-shaped chloroplast - a bit like a Chlamydomonas cell. There are a number of related genera which form colonies using mucus as a common matrix, but they differ in the numbers of cells involved, how tightly packed they are, and the shape of the colony. This image illustrates the way that a daughter colony of tightly packed cells is formed within a parental colony. Phase contrast.

Eudorina (you-door-ine-a) is a colonial volvocid - motile green alga. In this case 16 cells are embedded in a sphere of common mucus. Each individual cell has two flagella, and a cup-shaped chloroplast - a bit like a Chlamydomonas cell. There are a number of related genera which form colonies using mucus as a common matrix, but they differ in the numbers of cells involved, how tightly packed they are, and the shape of the colony. This image illustrates the flagella very well Phase contrast.

Eudorina, a motile colonial volvocid flagellate. Colonies may be cylindrical, elliptical or spherical as seen in this image. Colonies may be composed of 8 to 128 cells. This colony is composed of 16 individuals embedded in a clear gelatinous matrix. Two equal length flagella protrude through the matrix from each cell. Cells may be arranged in tiers or more randomly as seen here. One large bright green cup-shaped chloroplast. Small red stigma. Sexual and asexual reproduction occurs. From temporary rainwater pool in grass field near Boise, Idaho. Phase contrast.

Eudorina, a motile colonial volvocid flagellate. Colonies may be cylindrical, elliptical or spherical as seen in this image. Colonies may be composed of 8 to 128 cells. This colony is composed of 16 individuals embedded in a clear gelatinous matrix. Two equal length flagella protrude through the matrix from each cell. Cells may be arranged in tiers or more randomly as seen here. One large bright green cup-shaped chloroplast. Small red stigma. Sexual and asexual reproduction occurs. From temporary rainwater pool in grass field near Boise, Idaho. Brightfield.

Portrait of Pandorina. Colonial flagellate with bright green chloroplasts. Usually 8-16 cells each with 2 equal-length flagella all enclosed within clear gelatinous envelope. From freshwater pond near Boise, Idaho. Brightfield.

Pandorina morum is rare in Lake Kinneret. This specimen was collected at the shore by the Kinneret Limnological Laboratory in March 2006.

Volvox (vol-vox) is the iconic colonial volvocid - motile green alga. In this case hundred of cells are embedded in a sphere of common mucus. Each individual cell is tiny, linked to others by fine threads of cytoplasm, has two flagella, and a cup-shaped chloroplast - a bit like a Chlamydomonas cell. There are a number of related genera which form colonies using mucus as a common matrix, but they differ in the numbers of cells involved, how tightly packed they are, and the shape of the colony. Differential interference contrast.

Volvox (vol-vox) is the iconic colonial volvocid - motile green alga. In this case hundred of cells are embedded in a sphere of common mucus. Each individual cell is tiny, linked to others by fine threads of cytoplasm, has two flagella, and a cup-shaped chloroplast - a bit like a Chlamydomonas cell. There are a number of related genera which form colonies using mucus as a common matrix, but they differ in the numbers of cells involved, how tightly packed they are, and the shape of the colony. This is a detail of the surface of the colony, showing the flagella projecting from beyond the edge of the mucus. Differential interference contrast.