Articles | Volume 21, issue 1
https://doi.org/10.1144/jm.21.1.1
https://doi.org/10.1144/jm.21.1.1
01 May 2002
 | 01 May 2002

Classification of the meridionally costellate Cretaceous planktonic foraminifera

Hamed A. El-Nakhal

Abstract. The meridionally arranged rugosity, which is restricted to the Cretaceous globigerines, is given a superfamily taxonomic status. The globigerines displaying this type of ornamentation are placed in the Rugoglobigerinacea which is subdivided into two families the Rugoglobigerinidae and the Abathomphalidae. The Rugoglobigerinidae includes the forms having an umbilical primary aperture with a tegillum (Rugoglobigerina Brönnimann, Trinitella Brönnimann, and Plummerita Brönnimann). The Abathomphalidae includes the genera which have an umbilical–extraumbilical to spiro-umbilical primary aperture with a tegillum (Abathomphalus Bolli, Loeblich & Tappan, and Kassabella El-Nakhal), or a porticus (Meridionalla El-Nakhal, and Badriella n. gen.). Badriella is introduced as a new genus with B. mouradi n. sp. (= hypotype of Praeglobotruncana loeblichae Douglas) as a type species, to accommodate the meridionally costellate species with compressed chambers and umbilical–extraumbilical primary aperture, which were previously assigned to Praeglobotruncana Bermudez. The Rugoglobigerinacea may have evolved from a hedbergelline ancestor during the latest Albian via the development of the meridinally arranged rugosity.