Type host: Cryptotis parva parva (Say, 1823), Least shrew.

Type locality: NORTH AMERICA: U.S.A., Texas, Dallas County, 2.4 km E. of DeSoto off FM 1382 on Ellerson Road.

Geographic distribution: NORTH AMERICA: U.S.A., Texas.

Description of oocyst: Oocyst shape: subspheroid; number of walls: 2; wall thickness: 1.2; wall characteristics: outer, apparntly smooth, ~2/3 of total thickness; L x W: 16.4 x 15.3 (14-18 x 13-17); L/W ratio: 1.1 (1.0-1.2); M: absent; OR: absent; PG: 1, always attached to inner surface of wall; Distinctive features of oocyst: attachment of PG to inner surface of wall.

Description of sporocysts and sporozoites: Sporocyst shape: ovoid; L x W: 10.6 x 7.0 (9-11 x 6-8) with a smooth, thin, single-layered wall ~0.4; L/W ratio: 1.5 (1.4-1.8; SB: present as a thickend end of the sporocyst; SSB: present, ~1.6 high x 3.2 wide; PSB: absent; SR: present; SR characteristics: a large diffuse mass of granules filling sporocyst, ~5.7 x 4.9 (5-8 x 4-6); SP: 9-11 x 2.4, aranged head to tail with posterior ends recurved around one end of sporocyst, each with a centrally located N, but without RB. Distinctive features of sporocyst: large SSB and the curved SP without RB.

Prevalence: 1/14 (7%)

Sporulation: Exogenous. Oocysts sporulated in 7 days in 2.5% (w/v) aqueous potassium dichromate solution at ~23 ºC.

Prepatent and patent periods: Unknown.

Site of infection: Unknown. Oocysts recoverd from feces and intestinal contents.

Materials deposited: Symbiotype host is preserved in the Arkansas State University Museum of Zoology, ASUMZ No. 17740 (male), C.T. McAllister #91, 29 May 1987. Photosyntypes in the USNPC No. 87395.

Remarks: No other eimerian from shrews has a PG that has been reported to stick to the inner wall of the oocyst along with sporocysts with a SSB.

References: McAllister and Upton (1989).