-
Rhabdomonas, a swimming colourless euglenid. One flagellum emerges from near the anterior apex of the cell and beats in a figure-of-eight pattern. Surface with slightly spiralling ridges. Phase contrast.
-
Rhabdomonas spiralis (PRINGSHEIM,1942).Collected from a freshwater pond near Boise, Idaho.July 2007. DIC.
-
Portrait of Menoidium a colorless euglenoid flagellate. Strongly flattened. One side curved with the other more straight. One emergent flagellum. Stigma absent. Paramylon bodies are dimorphic with smaller round and larger elongate ring forms. Swims rotating on long axis. Highly refractile. From standing freshwater near Boise, Idaho. Brightfield.
-
Portrait of Menoidium a colorless euglenoid flagellate. Strongly flattened. One side curved with the other more straight. One emergent flagellum. Stigma absent. Paramylon bodies are dimorphic with smaller round and larger elongate ring forms. Swims rotating on long axis. From standing freshwater near Boise, Idaho. Phase contrast.
-
-
Menoidium pellucidum. 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.
-
Menoidium pellucidum. Empty pellicle observed in freshwater habitats in the vicinity of Broome, Western Australia in September 2003. This work was supported by the Australian Biological Resources Study.
-
Menoidium pellucidum. 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.
-
Anisonema (a-nice-o-neme-a), heterotrophic euglenid, glides over the substrate, with an anterior flagellum sweeping in front of the cell and with a long recurrent flagellum trailing over the substrate. As is common in the euglenids, the flagella seem to be very thick - especially as we can see here the recurrent flagellum. Occasionally jerks backwards. Common in intertidal sediments. Phase contrast.
-
Anisonema (a-nice-o-neme-a), a genus of heterotrophic euglenids commonly found in sediments. With one flagellum sweeping from side to side in front of the cell, and with a second flagellum following a hooked curve and then trailing behind the cell. The cells may periodically jerk backwards. Body not metabolic, no mouth visible by light microscopy. Phase contrast.
-
-
Anisonema has no chloroplasts. It has two flagella. One projects from the front of the cell and sweeps from side to side, the second flagellum trails behind the cell. This euglenid was collected at Obsidian Creek.
-
Gliding Anisonema cell, the anterior flagellum is to the top and beats with a sweeping motion, the second flagellum adheres to the substrate and tarils behind the moving cell. Phase contrast microscopy.
-
Anisonema (a-nice-o-neme-a) is one of the gliding heterotrophic euglenids, common. It has a distinctive pattern of movement, moving forwards with one thicker flagellum trailing and the other flagellum extending in front and sweeping from side to side in front of the cell, and then periodically jerking backwards. This movement is associated with the strong recurrent flagellum which, as it leaves the cell, follows a curve or hook. The genus is defined in part by not having a mouth that is visible by light microscopy, but this cell has clearly been eating diatoms. Differential Interference Contrast.
-
Anisonema (a nice-owe-knee-ma) acinus Dujardin, 1841. Cell outline is like a grain of barley. Cells are 21 to 40 microns long, 13 to 17 microns wide, flattened with a ventral groove, which diminishes posteriorly. There are about nine longitudinal pellicular grooves on each of the ventral and dorsal faces of the cell. In some cells, the grooves are fine and difficult to see but in a few cells they are deeper. The cells have a chisel-shaped ingestion organelle, which is difficult to observe at times. The anterior flagellum is about 1.5 times cell length and beats freely from side to side. The trailing posterior flagellum is about 1.7 to 3.2 times the length of the cell, is thicker than the anterior flagellum, lies in the ventral groove, and tapers posteriorly. The cells contain diatoms up to 25 microns long and one cell had four diatoms as long as 13 microns The flagellar pocket is located in the left side of the cell and the nucleus is in the right side. The cells glide smoothly, but jerk backwards when changing direction. Commonly observed.
-
Anisonema acinus Dujardin, 1841. Cell outline is like a grain of barley. Cells are 21 to 40 microns long, 13 to 17 microns wide, flattened with a ventral groove, which diminishes posteriorly. There are about nine longitudinal pellicular grooves on each of the ventral and dorsal faces of the cell. In some cells, the grooves are fine and difficult to see but in a few cells they are deeper. There is debate as to whether this species has an ingestion organelle, it was described without such an organelle, in some cells no organelle is seen, but in other cells otherwise indistinguishable from mouthless cells, a mouth can be seen. The anterior flagellum is about 1.5 times cell length and beats freely from side to side. The cells may eat large particles of food, such as diatoms. The trailing posterior flagellum is about 1.7 to 3.2 times the length of the cell, is thicker than the anterior flagellum, lies in the ventral groove, and tapers posteriorly. The flagellar pocket is located in the left side of the cell and the nucleus is in the right side. The cells glide smoothly, but jerk backwards when changing direction.
-
Anisonema acinus. 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.
-
Heterotrophic euglenoid photographed using DIC microscopy. Isolated by M. Virginia Sanchez Puerta from Little Sippewisset Pond, Woods Hole, MA, USA in October 2005
-
Anisonema ovale Klebs, 1893. Cells are oval, rigid and measure 11 microns long and 7 microns wide. The cell surface is smooth. The anterior flagellum is about the cell length and the posterior one is 1.5 times the cell length. Looks like Protaspis tegere and further study may reveal that this is not really an Anisonema.
-
Anisonema emarginatum Stokes, 1885. Cells are oval, rigid and 14 microns long. The cell surface is smooth. The anterior flagellum is about 2 times the cell length and the posterior one is about 2.5 times the cell length. Does not look like Anisonema.
-
Anisonema orbiculatum Lackey, 1940. Cells are 12-25 microns long, circular in outline, slightly rounded above but flattened ventrally, except for a wide, rather deep groove in the median plane. There are two flagella, emerging on the left ventral side through a somewhat crescentic sub-terminal mouth opening into a shallow gullet. Below this also on the left side is a relatively conspicuous nucleus. The short anterior flagellum is thin, about body length, the trailer stout, about twice body length and carried straight bade. No stigma or color. Numerous inclusions, mostly small spheres, in the cytoplasm. Pellicle firm, smooth. Movement principally a steady glide forward. No observed ingestion of food. Reproduction not seen.
-
Anisonema pusillum Stokes, 1886. Cells are spindle-shaped, rigid and 11 microns long. Dorsally convex and ventrally concave. The anterior flagellum is about the cell length and the posterior one is about 3 times the cell length. Although initially assigned to the genus Anisonema, it seems improbable that this assignment is correct.
-
Euglenopsis zabra Norris, 1961. Cells colourless, cylindrical, usually with a more or less pointed posterior end. A wide shallow groove extending only a short distance is present at the anterior end of the cell. A single flagellum approximately as long as the cell emerged from the center of the groove. The flagellar pocket is small and very difficult to see. Striations are not evident on the periplast. The protoplast contained a large number of small granules and one very large golden granule that was probably an ingested food body. The nucleus is near the base of the flagellar pocket. The cells are only slightly metabolic and swim slowly, rotating and with the flagellum directed forward. Length of cell 18 to 23. microns, width 5 to 10 microns
-
Sphenomonas quadrangularis Stein, 1878. Biflagellated, gliding euglenid, rigid, 17 - 30 microns (average 23.0 microns) long and 8 - 15 microns (average 11.5 microns) wide. Cell shape ellipsoid, anterior end of cell pointed, apically slightly oblique, posterior end of cell broadly rounded. Pellicle hyaline with 4 longitudinal strongly developed keels, each containing a series of small paramylon grains. In cruciate the cell shape looks square with concave sides and roundish angles. The anterior flagellum is about one or one and a half of the cell length and the recurrent flagellum about one quarter to one thirth of the cell length. The centre of cell always contains a large hyaline inclusion. The reservoir is situated in mid-line in the first quarter of the cell with an associated contractile vacuole.