Amastigomonas

This image was made from samples taken during a scientific cruise in the Pacific. Water was filtered to concentrate the organisms that were present, then dried onto a thin sheet of plastic and then shadowed with a fine layer of metal to provide contrast. The preparation was then observed with an electron-microscope. This technique has been used to document the diversity of marine microbes, especially, protists in the oceans.

Phase contrast image of a cell from ATCC strain number 50062. Image taken April 2006. Image shows theca around cell and anterior flagellum. ATCC data on this organism.

Amastigomonas bermudensis Molina and Nerad, 1991. Biflagellate heterotrophic protists with a ventral groove whose marginal folds extend anteriorly forming a sleeve that encloses the anterior locomotory flagellum. Flagella smooth and not acronematic (tapered at the tip), originating at the base of the sleeve. Beating of anterior flagellum lateral antero-sinistral, tracing an acute arc. Cells gliding on the substrate and feeding on bacteria. Recurrent flagellum located in the left side of the ventral groove and held close to the cell surface. Cell dorso-ventrally flattened. Dorsal surface convex, covered by a five-layered membrane. Ventral groove used for ingestion of bacteria and marginal folds firmly appressed to the substratum. Mitochondria with tubular cristae. Golgi apparatus present. Three bands of microtubules associated with the kinetosomes. One of these, the" MLS", shows an adjacent electron-dense, rod-like body. Single cells 3.0-5.5 microns wide x 8.0-11.5 microns long. Flagellar sheath 3.5-4.5 microns

Amastigomonas marina (Mylnikov, 1989) Mylnikov, 1999. This species is very metabolic, amoeboid, oval or elongated-oval. The cell body is 5 - 8 microns long and 2 - 4 microns wide. The anterior flagellum is 3 - 5 microns in length and is located inside a proboscis. The posterior flagellum is 8 - 16 microns long and part lies in a ventral groove. Forms plasmodia.

Amastigomonas (a-ma-stig-o-moan-ass), a commonly encountered gliding flagella from soils, freshwater and marine habitats., Cell enclosed in the dorsal lorica which makes the front flagellum seem thick. Group shot. Phase contrast.

Amastigomonas (a-ma-stig-o-moan-ass), one of two genera of apusomonad flagellates. Extremely common and widespread. Moves by gliding with one projecting flagellum and one flagellum trailing under the cell (just visible in a lighter groove in the posterior right half of the cell). Apusomonads are distinguished by having the dorsal surface of the cell covered by a thick layer or theca. this extends around the base of the anterior flagellum (the edges of it are visible in the image as two lines on either side of the flagellum. The anterior flagellum is acronematic - the tip region is much narrower than the rest. Eats bacteria and detritus. From marine and freshwater habitats, mostly in sediments but associated with almost all submerged surfaces.

Amastigomonas (a-ma-stig-o-moan-ass), a commonly encountered gliding flagellate from soils, freshwater and marine habitats., Cell enclosed in the dorsal lorica which makes the front flagellum seem thick. Recurrent flagellum lies under the cell and can be made out as a darker curving region. Phase contrast. Poor picture.

Amastigomonas (a-ma-stig-owe-moan-ass) debruynei de Saedeleer, 1931. Cells are 5 to 6.5 microns long, dorso-ventrally flattened and flexible but not amoeboid. The anterior flagellum emerges from the tip of a laterally directed sleeve and beats in a small angle. The posterior flagellum is slightly longer than the length of the cell, lies in a groove along the margin of the cell, trails under the cell and occasionally protrudes behind the cell. Strands of cytoplasm may be drawn out behind the cell. The nucleus is situated in the anterior left of the cell. Commonly observed.

Amastigomonas debruynei De Saedeleer, 1931. Cells are 5 to 6.5 microns long, dorso-ventrally flattened and flexible but not amoeboid. The anterior flagellum emerges from the tip of a laterally directed sleeve and beats in a small angle. The posterior flagellum is slightly longer than the length of the cell, lies in a groove along the margin of the cell, trails under the cell and occasionally protrudes behind the cell. Strands of cytoplasm may be drawn out behind the cell. The nucleus is situated in the anterior left of the cell.

Amastigomonas (a-ma-stig-o-moan-ass), a commonly encountered gliding flagella from soils, freshwater and marine habitats., Cell enclosed in the dorsal lorica which makes the front flagellum seem thick. Recurrent flagellum lies under the cell and can be made out as a darker curving region. Phase contrast.

Amastigomonas (a-ma-stig-owe-moan-ass) mutabilis (Griessmann, 1913) Molina and Nerad, 1991. Cells are elliptical, 11 to 16 microns long, dorso-ventrally flattened and flexible. There is a flexible sleeve around the base of the anterior flagellum. The anterior flagellum is about 0.5 times the length of the cell and is the same thickness as the posterior flagellum. The recurrent posterior flagellum is slightly longer than the cell and trails under the body, to which it attaches loosely in a slight groove. The nucleus is situated subapically near the right margin of the cell. Some cells have granules along side the recurrent flagellum.

Amastigomonas mutabilis (Griessmann, 1913) Molina and Nerad, 1991. Cells are elliptical, 11 to 16 microns long, dorso-ventrally flattened and flexible. There is a flexible sleeve around the base of the anterior flagellum. The anterior flagellum is about 0.5 times the length of the cell and is the same thickness as the posterior flagellum. The recurrent posterior flagellum is slightly longer than the cell and trails under the body, to which it attaches loosely in a slight groove. The nucleus is situated subapically near the right margin of the cell. Some cells have granules along side the recurrent flagellum.