eimeria maxima eimeria maxima eimeria maxima is a protozoan that causes coccidiosis in poultry. it is located in the middle part of the intestine, on either side of meckel's diverticulum, and frequently ascends into the duodenum. the lesions it causes are limited to the middle of the small intestine. eimeria maxima eimeria maxima oocysts scientific classification domain: eukaryota clade: diaphoretickes clade: sar clade: alveolata phylum: apicomplexa class: conoidasida order: eucoccidiorida family: eimeriidae genus: eimeria species: e. maxima binomial name eimeria maximatyzzer, 1929