Disseminated eosinophilic myositis was diagnosed in an alpaca that had been imported to the USA from Peru 5 years earlier. The myositis was associated with macroscopically visible large sarcocysts that were characterized histologically by septate compartments containing bradyzoites, and ultrastructurally by cyst walls composed of anastomosing villous protrusions. Two hours before death, the alpaca aborted an 8-month-gestation fetus, but no lesions were found in the uterus, placenta or fetus. Additional macroscopical findings included haemoabdomen and myofibre haemorrhage, degeneration and necrosis. It is believed that this is the first described case of clinical disease associated with a Sarcocystis sp. (probably S. aucheniae) in camelids.