Type host: Blarina brevicauda (Say, 1823), short-tailed shrew.

Type locality: NORTH AMERICA: USA, Illinois, Champaign County, Philo.

Geographic distribution: NORTH AMERICA: USA, Illinois.

Description of oocyst: Oocyst shape: spheroid to subspheroid; number of walls: 2; wall thickness: 1.5; wall characteristics: outer light brown, ~3/4 of total thickness, with indistinct striations, inner smooth; L x W: 21.3 x 18.4 (18-23 x 15-20); L/W ratio: 1.2 (1.0 x 1.4); M: absent; OR: present; OR characteristics: clear homogeneous refractile globules of 2 sizes, 1 globule ~5 with 4-5 smaller globules ~1-2 each; PG: present (?); Distinctive features of oocyst: the purported presence of both an OR and PG and the striated appearance of the outer wall.

Description of sporocysts and sporozoites: Sporocyst shape: elongate-piriform; L x W: 13.2 x 6.7 (12-14 x 6-8); L/W ratio: 2.0; SB: present; SSB: absent; PSB: absent; SR: present; SR characteristics: numerous small, scatteres granules; SP: banana-shaped, with a small anterior and a larger posterior RB. Distinctive features of sporocyst: piriform shape, strongly pointed at one end and SP with 2 RB.

Prevalence: 3 of 6 (50%).

Sporulation: Exogenous. Oocysts sporulated in 2.5% potassium dichromate solution at 25-26º C in 10 days.

Prepatent and patent periods: Unknown.

Site of infection: Unknown. Oocysts recovered from intestinal contents.

Materials deposited: None.

Remarks: There is some confusion about the internal structure of the sporulated oocysts. Todd et al. (1986) did not tell how they distinguished the PG from the various small globules of the OR. Also, they describe two sizes of OR globules and a PG, but their line drawing does not distinguish between them.

References: Todd et al. (1986).