The Euglenozoa are a large group of flagellate protozoa. They include a variety of common free-living species, as well as a few important parasites, some of which infect humans. There are two main subgroups, the euglenids and kinetoplastids. Euglenozoa are unicellular, mostly around 15-40 µm in size, although some euglenids get up to 500 µm long. Flagellata from Ernst Haeckels Artforms of Nature, 1904 Parasitic excavate (Giardia lamblia) Green alga (Chlamydomonas) Flagellates are cells with one or more whip-like organelles called flagella. ... Major groups Phototrophs    Euglenales    Eutreptiales Osmotrophs    Rhabdomonadales Phagotrophs    ?Heteronematales    ?Sphenomonadales The euglenids (also spelled euglenoids) are one of the best-known groups of flagellates, commonly found in freshwater especially when it is rich in organic materials, with a few marine and endosymbiotic members. ... Orders Trypanosomatida Bodonida The kinetoplastids are a group of flagellate protozoa, including a number of parasites responsible for serious diseases in humans and other animals, as well as various forms found in soil and aquatic environments. ... To help compare different orders of magnitude this page lists lengths between 10 micrometre and 100 micrometre (10-5 m and 10-4 m). ...

Most euglenozoa have two flagella, which are inserted parallel to one another in an apical or subapical pocket. In some these are associated with a cytostome or mouth, used to ingest bacteria or other small organisms. This is supported by one of three sets of microtubules that arise from the flagellar bases; the other two support the dorsal and ventral surfaces of the cell.^[2] A cytostome or cell mouth is a part of a cell specialized for phagocytosis, usually in the form of a microtubule-supported funnel or groove. ... Phyla Actinobacteria Aquificae Chlamydiae Bacteroidetes/Chlorobi Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Lentisphaerae Nitrospirae Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Verrucomicrobia Bacteria (singular: bacterium) are unicellular microorganisms. ... Microtubules are one of the components of the cytoskeleton. ...

Some other euglenozoa feed through the absorption, and many euglenids possess chloroplasts and so obtain energy through photosynthesis. These chloroplasts are surrounded by three membranes and contain chlorophylls a and b, along with other pigments^[1], so are probably derived from a captured green alga. Reproduction occurs exclusively through cell division. During mitosis, the nuclear membrane remains intact, and the spindle microtubules form inside of it.^[2] Chloroplasts are organelles found in plant cells and eukaryotic algae that conduct photosynthesis. ... This article needs additional references or sources for verification. ... Chlorophyll gives leaves their green color Space-filling model of the chlorophyll molecule Chlorophyll is a green pigment found in most plants, algae, and cyanobacteria. ... Divisions Chlorophyta Charophyta Streptophytina (Subdivision) The green algae are the large group of algae from which the embryophytes (higher plants) emerged. ... Mitosis is the process in which a cell duplicates its chromosomes to generate two identical cells. ...

The group is characterized by the ultrastructure of the flagella. In addition to the normal supporting microtubules or axoneme, each contains a rod (called paraxonemal), which has a tubular structure in one flagellum and a latticed structure in the other. Based on this, two smaller groups have been included here: the diplonemids and Postgaardi.^[3] An axoneme is the core scaffold of the eukaryotic cilia and flagella, which are projections from the cell made up of microtubules. ...

The euglenozoa are generally accepted as monophyletic. They are related to Percolozoa; the two share mitochondria with disc-shaped cristae, which only occurs in a few other groups.^[4] Both probably belong to a larger group of eukaryotes called the excavates.^[5] The Percolozoa are a group of colorless protists including many that can transform between amoeboid, flagellate, and encysted stages, collectively referred to as schizopyrenids or amoeboflagellates. ... The excavates are a major line of protists, often known as Excavata. ...

References

1. ^ ^{a b} T. Cavalier-Smith (1981). "Eukaryote Kingdoms: Seven or Nine?". BioSystems 14: 461-481. 
2. ^ ^{a b} David J. Patterson (1999). "The Diversity of Eukaryotes". American Naturalist 145: S96-S124. 
3. ^ Alastair G.B. Simpson (1997). "The Identity and Composition of Euglenozoa". Archiv für Protistenkunde 148: 318-328. 
4. ^ Baldauf et al. (2000). "A Kingdom-Level Phylogeny of Eukaryotes Based On Combined Protein Data". Science 290: 972-977. 
5. ^ Alastair G. Simpson (2003). "Cytoskeletal organization, phylogenetic affinities and systematics in the contentious taxon Excavata (Eukaryota)". International Journal of Systematic and Evolutionary Microbiology 53: 1759-1777.