Protozoans, are generally microscopic, unicellular organisms that are classified by the cellular structures responsible for movement (Pseudopodia, Flagella and Cilia). Protozoans possess membrane bound cellular organelles such as Nuclei, Food Vacuoles, and Lysosomes. Food is captured in many different ways, however in most cases, after capture, it is contained in a spherical bubble (Food Vacuole ) that is formed from the cell membrane and released into the cell interior.Food vacuoles fuse with membrane bound lysosomes that contain digestive enzymes. The enzymes break down food into units that protozoans can use for their own metabolic needs. In freshwater environments, water constantly passes into protozoan cells osmotically. If unchecked, the cell membrane will stretch and rupture. To counter this process most freshwater forms as well as those that live in low salinity environments have contractile vacuoles that collect the incoming water and then move it to the outside.
Flagellates are often classified as to whether or not they contain chloroplasts. Phytoflagellates (Autotrophs) (Euglena, Phacus and the dinoflagellates) contain chloroplasts allowing them to manufacture their own food photosynthetically. They generally have two anterior flagella, one of which is often shorter than the other. Zooflagellates on the other hand lack chloroplasts, have one to several flagella, and are heterotrophs. This division is somewhat arbitrary since many “phytoflagellate”genera such as Euglena have populations that lack chloroplasts.
A. Flagellated Protozoans Belonging To The Phylum Euglenozoa: Anisoma, Bodo, Euglena, Peranema, Phacus, and Petalomonas
1. Anisoma (Class Euglenophyceae, Family Sphenomonadaceae)
Anisonema, about 40 microns long, is flattened somewhat, from side to side. There are two visible flagella. The posterior flagellum has a broad base and is longer than the anterior flagellum; it can attach to the substratum and contract, pulling the cell body rapidly backwards with a jerky motion. The end of the flagellum often forms a hook-shaped loop. The shorter anterior flagellum waves (rotates) from side to side, pulling the cell body smoothly forward. The cell body sometimes rotates, either to the right or left, around the anterior-posterior longitudinal, central axis as they move forward. Food (Bacteria, detritus, and micro protozoans ) is taken into an anterior reservoir and incorporated into food vacuoles. Anisonema has a posterior contractile vacuole and lacks chloroplasts
2. Bodo (Class Kinetoplastea , Order Bodonida )
Bodo, about 15 microns long, has two flagella that arise from an anterior reservoir. One of them trails a relatively long distance beyond the posterior end of the cell body. The other flagellum is held straight out in front of the cell body. The tip of this flagellum rotates in a circle and is responsible for pulling the ciliate forward. The posterior section of the trailing flagellum often attaches to the substratum and then contracts pulling the entire flagellate backwards. Feeding was not observed, however detritus, bacteria and small protozoans have been observed in food vacuoles. Bodo lacks chloroplasts.
3. Petalomonas (Class Euglenophyceae, Family Sphenomonadaceae)
Petalomonas, about 45 microns long, has a single, long flagellum extending forward in a straight line. The anterior tip of the flagellum rotates, pulling the animal forward. The cell body of the flagellate is rigid and lacks chloroplasts. The cell has characteristic, thick, longitudinal, dorsal ridges and valleys. Small, round, green algal cells that seem to be contained in food vacuoles were observed.
3 . Euglena (Class Euglenophyceae , Family Euglenaceae )
Both types (1 and 2) of Euglena have one, thick, anterior flagellum. Both rotate on their central, longitudinal, anterior-posterior axis as they move forward. Both have a red stigma (Eye spot) at the anterior end and both have chloroplasts. Type 1 is flexible allowing the flagellate to roll up into a ball and extend the thinner anterior portion outward (Euglenoid Motion). Euglenoid motion allows the flagellate to push their way through thick sediments such as mud. The chloroplasts in Type 1 are round. Type 2 is relatively inflexible and unable to roll into a ball. Also, the chloroplasts in Type 2 are more elongate.
http://vimeo.com/115430609 (Zottoli) Euglena Type 2. X600. Anatomy and Movement
4. Phacus (Class Euglenophyceae, Family Euglenaceae)
Phacus, about 25 microns long, has a single flagellum extending from the anterior end. The cell body is rigid and as it moves forward it spirals around its central, longitudinal, anterior-posterior axis. The cell has many, round chloroplasts.
5. Peranema (Class Euglenophyceae, Family Peranemaceae)
Peranema is a flexible, flattened, colorless (Lacks Chloroplasts) euglenoid flagellate. The animal glides through the water with a slight side to side movement. A long flagellum extends in a more or less straight line anteriorly. The flagellum tip rotates in a circle drawing the animal forward. Peranema can move to the right or left by moving the entire flagellum in the desired direction. They can also change direction by contracting the cell body into a ball and extending the anterior end in along a new path. A second, much smaller flagellum (usually not visible) arises, along with the first from a “flask-shaped” clear, reservoir located at the anterior end. I observed Peranema force a small Euglena into a second reservoir, next to the reservoir containing the flagella, and form a food vacuole around it. Prey, too large to consume directly, may be taken into the reservoir and poked with an internal rod until they rupture. The released cytoplasm can then be incorporated into a food vacuole. They feed on detritus, bacteria and protozoans, etc.
B. Flagellated Protozoan Belonging To The Phylum Cryptozoa, Family Campylomonadaceae: Chilomonas
Chilomonas
Chilomonas, about 30 microns long, is abundant at all stations. The cell body, round in cross-section, is inflexible. Round starch grains fill most of the cell body. They lack chloroplasts. Two flagella, one short and one long, emerge from a slight depression at the anterior end (Visible). The flagellates move from side to side propelled by the flagella. Chilomonas rotates to the left or right, on its central anterior-posterior axis as it moves forward. When the flagellate touches an obstacle, it quickly moves away and reverses direction. It may repeat the process several times before it completes the process. There is one anterior contractile vacuole.
C. Flagellate In The Phylum Chrysophyta, Family Ochromondaceae: Uroglenopsis
Uroglenopsis
Uroglenopsis is a colonial chrysophyte. The cells have flagella that are directed outward. The cells do not seem to be connected with one other
Protozoans (Ciliates, Flagellates and Amoeboid Forms) , Desmids and Diatoms found in Mid to Upper Intertidal Sediments at two Freshwater Intertidal sites in Merrymeeting Bay and one site in the Lower Reaches of the Androscoggin River 
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