Diplomonadida

Hexamita (hex-a-mite-a), a free living diplomonad flagellate. With two sets of four flagella (in each set) inserting near the front of the cell. Three of the flagella are visible on the right side, and bits of all four on the right. Normally associated with anoxic habitats. Phase contrast.

Hexamita (hex-a-mite-a), a free living diplomonad flagellate. Diplomonads are so-called because most members of the group have two nuclei, and have clusters of up to 4 flagella emerging from opposing sides of the cell. They arise in grooves, which are believed to correspond to the ventral grooves of the excavate flagellates. Normally associated with anoxic habitats. Diplomonads are probably best known because one their members, Giardia, is significant as a parasite of the intestinal system, and because it is prominent in studies on the evolution of eukaryotic cells - "clinging resolutely" to the base of the eukaryotic tree as our best candidate for the most primitive eukaryote. They occur in organically enriched habitats and habitats with low levels of oxygen. They eat bacteria and may be able feed osmotrophically. Phase contrast.

Hexamita (hex-a-mite-a), a free living diplomonad flagellate. Diplomonads are so-called because most members of the group have two nuclei, and have clusters of up to 4 flagella emerging from opposing sides of the cell. They arise in grooves, which are believed to correspond to the ventral grooves of the excavate flagellates. Normally associated with anoxic habitats. Diplomonads are probably best known because one their members, Giardia, is significant as a parasite of the intestinal system, and because it is prominent in studies on the evolution of eukaryotic cells - "clinging resolutely" to the base of the eukaryotic tree as our best candidate for the most primitive eukaryote. The two nuclei are at the anterior (top) and the junction between them is seen as a dark line. The flagellar grooves and some of the flagella are evident. Phase contrast.

Hexamita (hex-a-mite-a), a free living diplomonad flagellate. Diplomonads are so-called because most members of the group have two nuclei, and have clusters of up to 4 flagella emerging from opposing sides of the cell. They arise in grooves, which are believed to correspond to the ventral grooves of the excavate flagellates. Normally associated with anoxic habitats. Diplomonads are probably best known because one their members, Giardia, is significant as a parasite of the intestinal system, and because it is prominent in studies on the evolution of eukaryotic cells - "clinging resolutely" to the base of the eukaryotic tree as our best candidate for the most primitive eukaryote. The two nuclei are at the anterior (top) and the junction between them is seen as a dark line. The flagellar grooves and some of the flagella are evident. Phase contrast.

Hexamita (hex-a-mite-a), a free living diplomonad flagellate. Diplomonads are so-called because most members of the group have two nuclei, and have clusters of up to 4 flagella emerging from opposing sides of the cell. They arise in grooves, which are believed to correspond to the ventral grooves of the excavate flagellates. Normally associated with anoxic habitats. Diplomonads are probably best known because one their members, Giardia, is significant as a parasite of the intestinal system, and because it is prominent in studies on the evolution of eukaryotic cells - "clinging resolutely" to the base of the eukaryotic tree as our best candidate for the most primitive eukaryote. All flagella can be seen with an eye of faith. Phase contrast.

Hexamita (hecks-a-mite-a) inflata. Dujardin, 1838. Cells are roundish to ovoid and about 6 - 10 microns long. Several contractile vacuoles are seen. The posterior end of the cell may be pointed or rounded. Two nuclei are located anteriorly, and two longitudinal cytostomal tubes are visible below the equator of the cell and on the ventral side of the cell. There are two sets of 4 flagella (total eight flagella), two medium flagella are about 1.3 - 1.5 times the cell length, four short flagella are about the cell length. These flagella insert anterio-laterally into a small depression on the anterior part of the cell. Two long flagella emerge from the cytostomal tube and are about 2 times the length of the cell. The long flagella normally cross each other. The cells move by skidding or swimming. Relatively common.

Hexamita inflata Dujardin, 1838. Cells are roundish to ovoid and about 6 - 10 microns long. Several contractile vacuoles are seen. The posterior end of the cell may be pointed or rounded. Two nuclei are located anteriorly, and two longitudinal cytostomal tubes are visible below the equator of the cell and on the ventral side of the cell. There are two sets of 4 flagella (total eight flagella), two medium flagella are about 1.3 - 1.5 times the cell length, four short flagella are about the cell length. These flagella insert anterio-laterally into a small depression on the anterior part of the cell. Two long flagella emerge from the cytostomal tube and are about 2 times the length of the cell. The long flagella normally cross each other. The cells move by skidding or swimming.

Portrait of the diplomonad Hexamita inflata (Dujardin 1838).Collected from sapropelic bottom sediments of a freshwater pond near Boise, Idaho. Phase contrast.

Portrait of the diplomonad Hexamita inflata (Dujardin 1838).

Portrait of the diplomonad Hexamita inflata (Dujardin 1838).Collected from sapropelic bottom sediments of a freshwater pond near Boise, Idaho. Phase contrast.

Portrait of the diplomonad Hexamita inflata (Dujardin 1838).Collected from sapropelic bottom sediments of a freshwater pond near Boise, Idaho. Phase contrast.

Spironucleus (spire-owe-new-clee-us) is a diplomonad flagellate. Like most genera in the group, there are two anterior nuclei, and arising in association with each nucleus is a group of four flagella. The flagella insert at the head of a lateral groove. Most members of this genus are parasites. Differential interference contrast.

Spironucleus (spire-owe-new-clee-us)is a diplomonad flagellate. Like most genera in the group, there are two anterior nuclei, and arising in association with each nucleus is a group of four flagella. The flagella insert at the head of a lateral groove. Most members of this genus are parasites. Differential interference contrast.

Giardia (gee-arr-dee-a), a diplomonad flagellate that is a common inhabitant of the human intestine. These are diplomonads, they have two nuclei (anterior), and two sets with four flagella each arising from the front end of the cell but extending to the side or posteriorly. Normally they clamp onto cells of the intestine, and heavy infections can lead to cells being ripped from the gut wall leading to bloody diarrhoea. Phase contrast.

Giardia (gee-arr-dee-a), a diplomonad flagellate that is a common inhabitant of the human intestine. These are diplomonads, they have two nuclei (anterior), and two sets with four flagella each arising from the front end of the cell but extending to the side or posteriorly. Normally they clamp onto cells of the intestine, and heavy infections can lead to cells being ripped from the gut wall leading to bloody diarrhoea. Phase contrast.