Dissolution of Molluscan Calcite by the Attached Foraminifer Vasiglobulina, New Genus (Vasiglobulininae, New Subfamily)

Abstract

The new foraminiferal genus Vasiglobulina comprises polymorphine species which possess an apertural system of hollow tubules radiating outward from the distal end of the final chamber lumen to the exterior surface of the test. The type species, Vasiglobulina alabamensis (Cushman and McGlamery), occurs in Gulf Coast sedimentary rocks which were deposited under shallow marine conditions during the upper Eocene to lower Miocene Epochs. It is ornamented by exterior spines which penetrate mollusc fragments, establishing a unique mode of permanent epifaunal attachment. These unusual morphological features furnish the bases for significant paleoecological and functional inferences. Five previously described species from Gulf Coast and European Tertiary localities are assigned to Vasiglobulina, establishing its known geologic range as upper Eocene to Pliocene.