Babesia crassa n.sp. (Sporozoa, Babesiidae) of domestic sheep in Iran.

A large Babesia sp., isolated from a sheep in Iran, provided to be serologically and morphologically different from B, motasi and B. ovis. The parasite, designated B. crassa n. sp., is characterized by the frequent occurrence of four organisms in one erythrocyte, which is the result of quadruple division and, in other cases, of two successive binary divisions. Parasited resulting from the first of two successive binary divisions are exceptionally broad. B. crassa appears to be of low pathogenicity for sheep and goats, to which it is also infective. The vector is unknown.