EIMERIAN GUILDS (APICOMPLEXA, EIMERIIDAE) IN RICHARDSONS (SPERMOPHILUS-RICHARDSONII) AND WYOMING (SPERMOPHILUS-ELEGANS) GROUND-SQUIRRELS

Feces of Richardson's ground squirrels (Spermophilus richardsonii) wer e examined to determine occurrence and prevalence of eimerian species and to compare eimerian guilds in these hosts to previously described guilds from Wyoming ground squirrels (Spermophilus elegans). Six speci es of Eimeria were collected from 100 Richardson's ground squirrels: E imeria beecheyi (36% infected); Eimeria bilamellata (13%); Eimeria cal lospermophili-Eimeria morainensis complex (41%); Eimeria lateralis (6% ); and Eimeria spermophili (9%). The species composition and prevalenc es were essentially identical in the 2 congeneric hosts. Three species were consistently more (>30%) and 3 were consistently less (<20%) pre valent in both host species. Furthermore, in both squirrel species the rare species were more prevalent in juveniles. Eimerian guilds such a s these may be common to many species of ground-dwelling sciurid squir rels. The report of E. beecheyi in Richardson's ground squirrels const itutes a new host record for this species.