Euglenophyceae

Phacus monilatus. 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.

Phacus balatonicus, short flattened euglenoid flagellate with no or negligible point at the posterior end, pellicle typically with single longitudinal fold in addition to the fine ridges. Many small discoid chloroplasts. Red stigma. Central circular paramylon body . This individual has shed its flagellum. From freshwater pond near Boise,Idaho. Brightfield.

Phacus contortus (BOURRELLY,1952). DIC.

Phacus contortus (BOURRELLY,1952). Brightfield.

Phacus contortus (BOURRELLY,1952). DIC.

Phacus contortus (BOURRELLY,1952).Brightfield.

Phacus pleuronectes, euglenoid flagellate with a rigid, leaf-shaped pellicle with fine longitudinal striations and short curved spinous posterior. Many discoid chloroplasts. Usually with one large circular central paramylon body (although two are seen in this individual). Red stigma. From freshwater pond near Boise, Idaho. Brightfield

Phacus pyrum or P. rudicula, a small euglenoid flagellate having a pyriform rigid pellicle thrown into folds (P. pyrum is described as round in cross section while P. rudicula is said to be more flattened as is the cell shown here, but it is likely the two are different forms of the same species). With oblique ridges and tapering, pointed posterior. Red stigma. These individuals have shed their flagella which are usually about 1½ body length. From freshwater pond near Boise, Idaho. Oblique illumination.

Portrait of the euglenid flagellate, Eutreptia viridis (Perty, 1852). The cells are fusiform during swimming. The pellicle shows fine spiral striations. There are two equal length emergent flagella. The cells swim rapidly with the anterior end tracing a wide circle. When cells stop swimming they exhibit marked metaboly (euglenoid movement). There are numerous bright green discoid to ellipsoid chloroplasts. Paramylon granules are rod or disc-shaped. There is a prominent red eyespot associated with one of the flagella. There is an anterior subapical opening into the reservoir. A single contractile vacuole empties into the reservoir. The nucleus is central in swimming cells. Eutreptia has been most often reported from marine and brackish habitats but is also found uncommonly in fresh water.Collected from surface samples of a slow flowing organically enriched freshwater stream overgrown with duckweed (Lemnaceae) near Boise, Idaho. DIC.

Eutreptiella (you-trep-tea-ella), a marine euglenid. The autotrophic euglenids (the ones with chloroplasts) are usually thought of as being freshwater organisms. A small number of species are found in marine habitats - the most commonly reported being Eutreptia (flagella equal in length) and Eutreptiella (flagella unequal in length) . Both have two or more emergent flagella, and these beat actively to propel the cell through the water. Euglenids have chlorophyll b in the plastids, and this gives them a bright green colour. The eyespot (stigma) lies outside the plastids. Euglenids are distinguished, in part, by the ridges under the cell membrane. Differential interference contrast.

Eutreptiella (you-trep-tea-ella), a marine euglenid. The autotrophic euglenids (the ones with chloroplasts) are usually thought of as being freshwater organisms. A small number of species are found in marine habitats - the most commonly reported being Eutreptia (flagella equal in length) and Eutreptiella (flagella unequal in length) . Both have two or more emergent flagella, and these beat actively to propel the cell through the water. Euglenids have chlorophyll b in the plastids, and this gives them a bright green colour. The eyespot (stigma) lies outside the plastids. Euglenids are distinguished, in part, by the ridges under the cell membrane. This detailed image shows the pellicular ridges and the individual plastids. Differential interference contrast

Eutreptiella (you-trep-tea-ella), a marine euglenid. The autotrophic euglenids (the ones with chloroplasts) are usually thought of as being freshwater organisms. A small number of species are found in marine habitats - the most commonly reported being Eutreptia (flagella equal in length) and Eutreptiella (flagella unequal in length) . Both have two or more emergent flagella, and these beat actively to propel the cell through the water. Euglenids have chlorophyll b in the plastids, and this gives them a bright green colour. Differential interference contrast.

Eutreptiella (you-trep-tea-ella), a marine euglenid. The autotrophic euglenids (the ones with chloroplasts) are usually thought of as being freshwater organisms. A small number of species are found in marine habitats - the most commonly reported being Eutreptia (flagella equal in length) and Eutreptiella (flagella unequal in length) . Both have two or more emergent flagella, and these beat actively to propel the cell through the water. Euglenids have chlorophyll b in the plastids, and this gives them a bright green colour. The eyespot (stigma) lies outside the plastids. In this preparation some of the cells lacking flagella and aggregated to form a structure referred to as palmelloid. Differential interference contrast.

Eutreptiella (you-trep-tea-ella), a marine euglenid. The autotrophic euglenids (the ones with chloroplasts) are usually thought of as being freshwater organisms. A small number of species are found in marine habitats - the most commonly reported being Eutreptia (flagella equal in length) and Eutreptiella (flagella unequal in length) . Both have two or more emergent flagella, and these beat actively to propel the cell through the water. Euglenids have chlorophyll b in the plastids, and this gives them a bright green colour. The eyespot (stigma) lies outside the plastids. In this preparation some of the cells lacking flagella and aggregated to form a structure referred to as palmelloid. The central pyrenoid and radiating elements of the plastids are very evident. Differential interference contrast.

Colacium (coal-ace-ee-um) is a euglenid flagellate in which the cells are attached to the substrate b y means of a mucoid stalk. the euglenids are attached to the stalks by their anterior region. The individual cells may break free from the stalks and swim away, at which time they are indistinguishable from members of the genus Euglena. Plastids and eyespots can be discerned in some cells. Phase contrast.

Colacium (coal-ace-ee-um) is a euglenid flagellate in which the cells are attached to the substrate b y means of a mucoid stalk. the euglenids are attached to the stalks by their anterior region. The individual cells may break free from the stalks and swim away, at which time they are indistinguishable from members of the genus Euglena. detail of two cells showing plastids, region of nuclei, and eyespots (the refractile orange granules in the cells). Phase contrast.

Colacium (coal-ace-ee-um) is a euglenid flagellate in which the cells are attached to the substrate b y means of a mucoid stalk. the euglenids are attached to the stalks by their anterior region. The individual cells may break free from the stalks and swim away, at which time they are indistinguishable from members of the genus Euglena. Plastids and eyespots can be discerned in some cells as can the location of the nuclei. Phase contrast.

Colacium (coal-ace-ee-um) is a euglenid flagellate in which the cells are attached to the substrate b y means of a mucoid stalk. the euglenids are attached to the stalks by their anterior region. As in this species, the stalks may branch and form moderately large aggregates. The individual cells may break free from the stalks and swim away, at which time they are indistinguishable from members of the genus Euglena. Phase contrast.

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.