Abstract
Babesia moshkovskiiwas found in the blood of 6 of 30 downy (D) Prairie Falcons and in none of 5 adults (A) from Wyoming. Intestinal parasites included Neodiplostomum (C) spathula (A,3), Cladotaenia globifera, (A,1), Physaloptera sp., (A,1), and Serratospiculum amaculatum, (a,4). ornithodorus concanensis, (D,3), Thrassis francisi, (D,1), Opisocrostis sp., (D.1), Degeeriella rufa, (D,2), Simulium (E.) canonicola (D,2), and an unidentified hippoboscid fly, (D,2) were external parasites. It is considered that the soft tick, O. concanensis, is the most likely vector of the hematozoon. The morphological forms of B.moshkovskii are described and discussed. This is the first report of an avian babesoid on this continent.