Rastrimonas

Rastrimonas is a monotypic genus of parasitic alveolates in the phylum Apicomplexa. It contains the single species Rastrimonas subtilis. It was described in 2002 from the free-living cryptomonad and placed in the new genus Cryptophagus.^[1] The following year this was renamed Rastrimonas.^[2]

Life cycle[]

The life cycle begins with the adhesion of the anterior tip of the parasite, followed by the penetration of the flagellated sporozoite, into a specialized region at the base of the flagellum of an individual Chilomonas. The trophozoite grows within the host cytoplasm.

After 4 to 5 successive nuclear mitoses the sporozoites bud on the surface where they acquire flagella, micronemes, and other apical structures. Mitosis is closed with an external spindle lacking a .

A sporangium is not formed, but a cyst may occur within the host.

Description[]

The sporozoite has an elongated shape with an apical complex, a central nucleus and two flagellae which are inserted at the base of the .

Two microtubular roots lie deep to the plasma membrane and are attached to each basal body.

The apical complex consistes of a set of 10–14 micronemes and a train of dumbbell-like vesicles which converge toward the tip of the pseudoconoid. The micronemes are outlined by a four microtubule fibre. The dumbbell-like vesicles are associated with a three microtubules in a rakelike fibre.

The mitochondrial network has few cristae and a fairly reduced dense matrix.

One large vacuole containing microfilamentous material is present and is connected to the nuclear envelope.

The Golgi body is situated close to the nucleus.

References[]