Synonym: Eimeria palustris Hertel and Duszynski, 1987, nomen preocc; non Eimeria palustris Barnard, Ernst and Stevens, 1971.

Type host: Sorex tenellus Merriam, 1895, Inyo shrew.

Other hosts: Sorex cinereus Kerr, 1792, Maskd shre; Sorex fontinalis Hollister, 1911, Maryland shrew; Sorex fumeus Miller, 1895, Smokey shrew; Sorex haydeni Baird, 1858, Hayden shrew; Sorex longirostris Bachman, 1837, Southeastern shrew; Sorex ornatus Merriam, 1895, Ornate shrew; Sorex pacificus Coues, 1877, Pacific shrew; Sorex palustris Richardson, 1828, Northern water shrew; Sorex trowbridgii Baird, 1858, Trowbridge shreww; Sorex vagrans Baird, 1858, Vagrant shrew.

Type locality: NORTH AMERICA: U.S.A., New Mexico, Santa Fe County, 8 km N, 12.9 km E, Santa Fe.

Geographic distribution: NORTH AMERICA: Canada, Manitoba, Ontario; U.S.A., Arizona, California, Colorado, Florida, Massachusetts, Minnesota, New Mexico, Oregon, Pennsylvania, Vermont, Virginia, Washington.

Description of oocyst: Oocyst shape: shperoid to slightly subspheroid; number of walls: only 1 obvious layer; wall thickness: < or = 1.0; wall characteristics: yellow, slightly sculptured and gives striated appearance in optical cross section; L x W: 17.1 x 16.6 (12-22 x 12-21) L/W ratio: 1.0 (1.0-1.3) M: absent; OR: absent; PG: usually 1-2. Distinctive features of oocyst: striated appearance of wall when viewed in cross section.

Description of sporocysts and sporozoites: Sporocyst shape: ovoid; L x W: 10.8 x 6.5 (6-14 x 4-8); L/W ratio: 1.7 (1.0-2.9) SB: present; SSB: absent; PSB: absent; SR: present; SR characteristics: dispersed granules; SP: with 1-2 distinct RBs. Distinctive features of sporocyst: small size with high L/W ratio.

Prevalence: 12/63 (19%) S. cinereus; 2/7 (29%) S. fontinalis; 5/16 (31%) S> fumeus; 1/4 (25%) S. haydeni; 5/8 (63%) S. longirostris; 1/2 (50%) S. ornatus; 1/12 (8%) S. pacificus; 8/41 (20%) S. palustris; 1/2 (50%) S. tenellus; 4/105 (4%) S/ trowbridge; 14/112 (12.5%) S. vagrans.

Sporulation: Exogenous. Oocysts sporulated in 7-10 days in 2.5% aqueous (w/v) potassium dichromate solution at ~23 º C.

Prepatent and patent periods: Unknown.

Site of infection: Unknown. oocysts recovered from feces and intestinal contents.

Materials deposited: Skin, skull, skeleton and tissues of the symbiotype host are preserved in the Mammal Division of the MSB, UNM: MSB No. 41120 (NK 1027, female), J.M. Evans #010, 8 July 1979. Photosyntypes in the USNPC No. 86351.

Remarks: Sporulated oocysts of E. longirostris somewhat resemble those of Eimeria suncus Ahluwalia, Singh, Arora, Mandal and Sarkar, 1979 from the common house shrew (Suncus suncus) in India. They differ from oocysts of E. suncus by having a single-layered, rough oocyst wall (vs. bilayered, smooth), in L/W ratio (1.0 vs. 1.3), by lacking a micropyle cap and by the presence of PBs.

References: Hertel and Duszynski (1987)