EIMERIAN SPECIES (APICOMPLEXA, EIMERIINA) IN GUNNISONS PRAIRIE DOGS (CYNOMYS-GUNNISONI ZUNIENSIS) AND ROCK SQUIRRELS (SPERMOPHILUS-VARIEGATUS GRAMMURUS) FROM SOUTHEASTERN UTAH

Eimeria callospermophili-morainensis (prevalence = 78.9%), E. beechevi (62.6%), E. spermophili (9.8%), E. bilamellata (8.1%), E. larimerensi s (3.3%), E. cynomysis (1.6%), and 1 unidentified eimerian species wer e recovered from 123 fecal samples of Gunnison's prairie dogs (Cynomys gunnisoni zuniensis) collected in southeastern Utah. Eimeria spermoph ili has not been reported previously in any prairie dog species, and G unnison's prairie dog is a new host record for 7 of the preceding spec ies. Eighty-five percent of the samples contained at least 1 eimerian species, with multispecific infections of 2-4 species in 65% of the 12 3 samples. Species richness was 2.0 species/infected host. Eimeria bee cheyi (100%), E. morainensis (85.7%), E. callospermophili (57.1%), and E. bilamellata (28.6%) also were recovered from 7 rock squirrels (Spe rmophilus variegatus grammurus). Individuals harbored from 2-5 eimeria n species (species richness = 3.5). Eimeria beecheyi and E. morainensi s have not been reported previously infecting rock squirrels. The unid entified eimerian species was recovered from 6 of the 123 prairie dog samples (4.9%) and 5 (71.4%) rock squirrels live-trapped in southeaste rn Utah. The eimerian complex described for these 2 sympatric host spe cies is similar to those described in Wyoming ground squirrels and sev eral other sciurid species. We propose that the ability of the spermop hiline species of Eimeria to infect related host species contributes t o the stability and persistence of this eimerian guild.