Late Cretaceous (Santonian-Maastrichtian) serial foraminifera with pore mounds or pore mound-based ornamentation structures

Abstract

Pore mounded ornamentation has been reported from Late Cretaceous (Santonian-Maastrichtian) benthic and planktic foraminifera with biserial and/or triserial chamber arrangement. This high resolution SEM/ESEM-based study shows that the pore mounds are morphologically diverse in shape (circular and elliptical) and degree of development (incipient and well-developed). Pore mound distribution patterns show significant variability, with scattered pore mounds observed most often. Pore mounds can fuse to form pore mound-based structures, such as keels [i.e., Pseudouvigerina cristata (Marsson, 1878)] and ornamented platforms [i.e., Trachelinella watersi (Cushman, 1927a)]. A new genus, Elongateporeia, is identified for a group of late Santonian-late Campanian biserial benthics with elongate to slit-like pores ornamented with incipient to well-developed elliptical pore mounds. Three new species are described: Bolivinoides mirabilis, Elongateporeia elongatoporosa and Neobulimina newjerseyensis.