Mixotricha paradoxa is a species of protozoan that lives inside the gut of the Australian termite species Mastotermes darwiniensis. It is composed of five different organisms: three bacterial ectosymbionts live on its surface for locomotion and at least one endosymbiont lives inside to help digest cellulose in wood to produce acetate for its host(s). Mixotricha mitochondria degenerated in hydrogenosomes and mitosomes and lost the ability to produce energy aerobically by oxidative phosphorylation. The mitochondria-derived nuclear genes were however conserved. Discovery The name was given by the Australian biologist J.L. Sutherland, who first described Mixotricha in 1933. The name means "the paradoxical being with mixed-up hairs" because this protist has both cilia and flagella, which was not supposed to be the case with protists where they were supposed to have one or the other but not both. Behavior Mixotricha is a species of protozoan that lives inside the gut of the Australian termite species Mastotermes darwiniensis and has multiple bacterial symbionts. Mixotricha is a large protozoan long and contains hundreds of thousands of bacteria. It is an endosymbiont and digests cellulose for the termite. Trichomonads like Mixotricha reproduce by a special form of longitudinal fission, leading to large numbers of trophozoites in a relatively short time. Cysts never form, so transmission from one host to another is always based on direct contact between the sites they occupy. Anatomy Species of the order Trichomonadida typically have four to six flagella at the cell's apical pole, one of which is recurrent - that is, it runs along a surface wave, giving the aspect of an undulating membrane. Mixotricha paradoxa have four weak flagella that serve as rudders. It has four large flagella at the front end, three pointing forwards and one backward. The basal bodies are also bacteria, not spirochaetes but oval, pill-shaped bacteria. There is a one-to-one relationship between a bracket, a spirochaete, and a basal bacterium. Each bracket has one spirochaete running through it and one pill bacterium at its base as the basal body. It has not been shown definitely, but the basal bodies could also be making cellulases that digest wood. Endosymbionts for biochemical processes At least one endosymbiont lives inside the protist to help digest cellulose and lignin, a major component of the wood the termites eat. The cellulose gets converted to glucose then to acetate, and the lignin is digested directly to acetate. The acetate probably crosses