Location: Unknown. Oocysts found in feces.
Geographic Distribution: North America.
Prevalence: This species is relatively uncommon. Christensen (1941) found it in 6 calves in Alabama, never in large numbers. Hasche and Todd (1959) found it in 11% of 355 cattle in Wisconsin.
Morphology: This species has been described by Christensen (1941). The oocysts are 9 to 13 by 8 to 12 u with a mean of 11.0 by 10.4 u. Their length-width ratio is 1.00 to 1.3 with a mean of 1.06. They are typically subspherical, but vary from spherical to bluntly ellipsoidal. A micropyle is absent. The oocyst wall is thin, smooth, homogeneous, transparent, of uniform thickness thruout, and colorless to faintly yellowish. An oocyst residuum and polar granule are absent. The sporocysts are pale, spindle-shaped, without a sporocyst residuum. The sporulation time is 4 to 5 days.
The oocysts of this species might be confused with the smaller, subspherical oocysts of E. ellipsoidalis or E. zurnii, but Christensen (1941) considered that they can be differentiated by their more fragile appearance, their more delicate wall, and by their requiring 2 days longer to sporulate.
Life Cycle: Unknown.