Cysticerci of Taenia mustelae in the fox squirrel.

The liver of a fox squirrel (Sciurus niger rufiventer) contained many clear, spherical cysts approximately 1 mm in diameter throughout the parenchyma. On dissection, most of these exhibited a dense, white area with four muscular suckers at a single point on the bladder. Based on the size of the organisms, the characteristically tiny hooks on the scolex and the location of the cysts in this host, the parasites were identified as cysticerci of Taenia mustelae. This is the first report in this host. The parasites were surrounded by an intense inflammatory response consisting primarily of lymphocytes mixed with some eosinophils, and early deposition of fibrous connective tissue.