Difflugia fragosa Hempel, 1902
Diagnosis: Shell composed of fine sandgraines, irregular in form, about one and a half times as long as wide, widest at fundus, thence tapering to the mouth where it is slightly constricted; mouth irregular, slightly notched. Fundus with one to eight spines or bulges, rounded at tip. These originate at about the middle of the test, giving an irregular outline to the test when seen from above. Pseudopodia simple, fine and few in number.
Dimensions: Length 230 µm, width 150 µm.
Ecology: Fresh water, Illinois River, USA
Literature: Hempel, A. (1902): A list of the Protozoa and Rotifera found in the Illinois River and adjacent lakes at Havana - Bull. Illinois State Labor. of Nat. Hist., Urbana, Ill., p. 320-321.