Euglenas

This phase contrast micrograph of an un-named species of euglena shows the way that euglenid flagella beat. The flagellum is thrown into loops and these are pushed along the flagellum from base to tip. Several loops can be seen here. Cell with grass-green plastids and red eyespot.

Euglena. Collected by ATOL team in Cedar Pond, Woods Hole during the Protistology Workshop at MBL, October-November 2005. Isolation and art by Adrian Reyes-Prieto.

Moving Euglena. By Bob Moore and Dan Lahr

Moving Euglena. By Bob Moore and Dan Lahr.

Euglena sanguinea. Cell observed in freshwater habitats in the vicinity of Broome, Western Australia in September 2003.  This work was supported by the Australian Biological Resources Study.

Euglena sanguinea. Detail showing the red granules which give this species its distinctive colour. Cell observed in freshwater habitats in the vicinity of Broome, Western Australia in September 2003.  This work was supported by the Australian Biological Resources Study.

Portrait of Euglena sanguinea (probably synonymous with E. rubra and some other red euglenae). This species has numerous red granules containing astaxanthin among other carotenoids scattered in the cytoplasm. The granules, which may provide protection of cell structures from UV-B radiation, concentrate in a central mass under low light conditions and disperse in bright light (as seen in this image). The cell is has a blunt point posteriorly and a broadly rounded anterior. The large stigma (left anterior in this image) has the same coloration as the red cytoplasmic granules. The plastids are elongate, thin and tend to parallel the fine pellicular striations. The flagellum is about body length. Cells are flexible but not highly metabolic. The central nucleus is seen in this image. Small paramylon grains of various shapes are scattered through the cytoplasm. Swimming is slow with rotation around the long axis. Cells often appear to glide on the substrate. From stagnant fresh water with abundant rotting vegetation near Boise, Idaho. DIC optics

Portrait of Euglena sanguinea (probably synonymous with E. rubra and some other red euglenae). This species has numerous red granules containing astaxanthin among other carotenoids scattered in the cytoplasm. The granules, which may provide protection of cell structures from UV-B radiation, concentrate in a central mass under low light conditions (as seen in this image) and disperse in bright light. The cell is has a blunt point posteriorly and a broadly rounded anterior. The large stigma (mid-anterior in this image) has the same coloration as the red cytoplasmic granules. The plastids are elongate, thin and tend to parallel the fine pellicular striations. The flagellum is about body length. Cells are flexible but not highly metabolic. The nucleus is seen in the posterior 1/3 in this image. Small paramylon grains of various shapes are scattered through the cytoplasm. Swimming is slow with rotation around the long axis. Cells often appear to glide on the substrate. From stagnant fresh water with abundant rotting vegetation near Boise, Idaho. DIC optics.

"Palmelloid" or resting phase of Euglena sanguinea. This species has numerous red granules containing astaxanthin among other carotenoids scattered in the cytoplasm. The granules, which may provide protection of cell structures from UV-B radiation, concentrate in a central mass under low light conditions and disperse in bright light. Under inhospitable conditions cells enter the palmelloid phase. The normally elongate cells shed their flagella and encyst within a clear mucous coat (seen in this image) and reduce metabolic activity. Cell division within the mucous cysts may occur with the aggregate of cells spreading to form large sheets. From stagnant fresh water with abundant rotting vegetation near Boise, Idaho. DIC optics.

Euglena sanguinea is one of several nominal species in the genus that are capable of producing dark red granules. This species can withdraw and extend the granules in the cell, and the species may occur in sufficient numbers to color water green or red (from which they have got the ne 'traffic-light euglena'). The anterior flagellum is often short or does not emerge at all.

Euglena sanguinea is one of several nominal species in the genus that are capable of producing dark red granules. This species can withdraw and extend the granules in the cell. The anterior flagellum is often short or does not emerge at all. In this cell the flagellum is well developed. The larger clear inclusions are paramylon deposits.

Euglena sanguinea is one of several nominal species in the genus that are capable of producing dark red granules. This image focussed on the surface shows the strand-like margins of the green platids, various spherical paramylon granules, and the red color. Differential interference contrast image.