Euglenas

Euglena velata. Plastids with pyrenoids. Cell observed in freshwater habitats in the vicinity of Broome, Western Australia in September 2003. This image was taken using differential interference contrast optics.   This work was supported by the Australian Biological Resources Study.

Euglena velata. Cell observed in freshwater habitats in the vicinity of Broome, Western Australia in September 2003. This image was taken using differential interference contrast optics.   This work was supported by the Australian Biological Resources Study.

Euglena velata. Cell observed in freshwater habitats in the vicinity of Broome, Western Australia in September 2003. This image was taken using differential interference contrast optics.   This work was supported by the Australian Biological Resources Study.

This image shows two species of Euglena, Euglena velata (the green cells) and Euglena sanguinea (the red cells). Low magnification image.

Euglena velata is a medium-sized Euglena with large flat plastids with central pyrenoid regions. The cytoplasm often has many fine granules. Differential interference contrast optics.

Euglena velata is a medium-sized Euglena with large flat plastids with central pyrenoid regions. The cytoplasm often has many fine granules. Eyespot and paramylon polysaccharide by-product are visible. Animations by Rosemary Arbur of flagellar beat patterns are available here.Differential interference contrast optics.

Portrait of the euglenoid flagellate (Ehrenberg,1830).Collectedfrom a slow-flowing freshwaterstream near Boise, Idaho. November,2005.DIC.

Euglena agilis. Cell observed in freshwater habitats in the vicinity of Broome, Western Australia in September 2003. This image was taken using differential interference contrast optics.   This work was supported by the Australian Biological Resources Study.

Euglena agilis. Cell observed in freshwater habitats in the vicinity of Broome, Western Australia in September 2003. This image was taken using phase contrast optics.   This work was supported by the Australian Biological Resources Study.

Euglena mutabilis (you-glean-a mew-tab-ill-iss), is a moderately long but usually thin worm-like euglena. It may or may not have an emerging flagellum, and distinguished from similarly-shaped species by the relatively small number of large chloroplasts. The image also shows (from anterior - top): flagellar pocket, stigma or eyespot, small paramylon granules, and nucleus in the middle of the cell. Typically very metabolic - squirming a lot as is suggested by the different profiles in this image. Differential interference contrast.

Euglena mutabilis is a worm like gliding Euglena which rarely swims. With more than 10 (up to 100), disk-shaped, plastids situated just below surface. Plastids are disc shaped and pressed against the inner face of the pellicle. Phase contrast.

Euglena (you-glean-a) is the iconic genus of euglenoid flagellates. The body is typically spindle-shaped, although two flagella arise in a pocket within the cell only one emerges (and sometimes none). The body can squirm, and the cell has one to many chloroplasts. At the anterior of the body a thin channel (flagellar canal) leads to the flagellar pocket, and alongside this is a contractile vacuole. A red eyespot or stigma is assoicated with the bottom of the flagellar canal. This image is included to show the pattern of beat of the flagellum. It is called a whiplash beat because a loop is made to progress along the flagellum. Flagella are usually held pointed to the side and slightly to the rear. The progression of the loop along the flagellum makes the cell move forward in a spiral path. Phase contrast.

Euglena (you-glean-a) is the iconic genus of euglenoid flagellates. The body is typically spindle-shaped, although two flagella arise in a pocket within the cell only one emerges (and sometimes none). The body can squirm, and the cell has one to many chloroplasts. At the anterior of the body, a thin channel (flagellar canal) leads to the flagellar pocket, and alongside this is a contractile vacuole. A red eyespot or stigma is associated with the bottom of the flagellar canal. Phase contrast.

Euglena (you-glee-na) is the iconic representative of the euglenids, a group of flagellates common in freshwaters and marine sediments. Some euglenids have bright green chloroplasts, such as this one, and there is also a small red eyespot located close to the anterior (to the right, here) of the cell. This species, probably E. mutabilis, is worm-like, squirms and has no emergent flagella. Differential interference contrast. Material from Nymph Creek and Nymph Lake, thermal sites within Yellowstone National Park, photograph by Kathy Sheehan and David Patterson.

Euglena sanguinea - a brightfield portrait of this slow swimming species pigmented with hematochrome granules. Granules aggregate as seen here in low light conditions and disperse with increases in either water temperature or light intensity. Flagellum typically body length but not seen here. Small spindle shaped chloroplasts often spirally aligned with pellicular striations. Also referred to as E. rubra. Collected from freshwater pond near Boise, Idaho.

Detail of the anterior end of a Euglena cell, collected at Beaver Lake, showing the flagellar pocket, a very short flagellum with a swollen basal region (the flagellum is not long enough even to project from the front of the cell). The eyespot is closely associated with the flagellum.

This image of Euglena, collected from Beaver Lake, emphasizes the disk- shaped chloroplasts. The front of the cell is to the left. The light area is called the reservoir. Adjacent to this region is the red eyespot that helps to control the direction in which the cells move. The granular region in the center of the cell is the nucleus.

Euglena. Cyst observed in freshwater habitats in the vicinity of Broome, Western Australia in September 2003. This image was taken using differential interference contrast optics.   This work was supported by the Australian Biological Resources Study.

Euglena. Cyst observed in freshwater habitats in the vicinity of Broome, Western Australia in September 2003. This image was taken using differential interference contrast optics.   This work was supported by the Australian Biological Resources Study.

Euglena. The picture to the left shows euglenids and some diatoms concentrated within a narrow beam of light using photokinetic reactions to changing light intensities. The image to the right shows the cells beginning to move outwards after the beam of light has been 'opened up'.   This work was supported by the Australian Biological Resources Study.

Single cell without an emergent flagellum. The eyespot is the red structure near the front of the cell, and there is a contractile vacuole near it. the clear, slightly speckled, region near the center of the cell is the nucleus.

Collected from Cumloden Swamp on July 8, 2002.