Piroplasmida


Piroplasmida is an order of parasites in the phylum Apicomplexa. They divide by binary fission and as sporozoan parasites they possess sexual and asexual phases. They include the tick parasites Babesia and Theileria.

Description

They are minute rounded or parasites found within erythrocytes, or other circulating or endothelial cells of vertebrates, where they reproduce by. The trophozoite stage is separated from erythrocyte by a single membrane. This distinguishes them from other blood parasites that usually have at least two membranes.
An complex with a polar ring and rhopteries occurs, but without a and usually without associated pellicular microtubules. They lack flagella and do not form either oocysts or spores.
The known vectors are ticks or leeches in which they undergo ; sexual reproduction probably occurs in the vector.