Two distinct borehole geometries cylindrical and paraboloidal, are reported in brachiopod shells from the Edwardsville Formation (Lower Mississippian) of southern Indiana. The cylindrical boreholes are interpreted to be the result of an infaunal, parasitic polychaete worm. The boreholes with a paraboloid geometry reflect predatory behavior and closely match the geometry of boreholes produced by Recent boring gastropods. Because a gastropod that could have been responsible for the paraboloid boreholes is not present in the fauna and because gastropods currently are not believed to have attained a boring habit until the Mesozoic, the paraboloid boreholes are only questionably assigned a gastropod origin. These boreholes add further questions to the evolutionary history of predatory boring gastropods.