An amastigote is a protist cell that does not have visible external

flagella A flagellum (; ) is a hairlike appendage that protrudes from certain plant and animal sperm cells, and from a wide range of microorganisms to provide motility. Many protists with flagella are termed as flagellates. A microorganism may have f ...

cilia The cilium, plural cilia (), is a membrane-bound organelle found on most types of eukaryotic cell, and certain microorganisms known as ciliates. Cilia are absent in bacteria and archaea. The cilium has the shape of a slender threadlike projecti ...

. The term is used mainly to describe an intracellular phase in the life-cycle of trypanosomes that replicates. It is also called the leishmanial stage, since in ''

Leishmania ''Leishmania'' is a parasitic protozoan, a single-celled organism of the genus '' Leishmania'' that are responsible for the disease leishmaniasis. They are spread by sandflies of the genus ''Phlebotomus'' in the Old World, and of the genus '' ...

'' it is the form the parasite takes in the vertebrate host, but occurs in all trypanosome genera.

References

Kinetoplastids {{Protist-stub