Punctuationlism and Gradualistic Evolutionary Trends of Eight Phylogenetic Lineages of Maastrichtian to Eocene and Recent Benthic Foraminifera from the Tethys

Abstract

Minor differences in the morphology of the test, wall structure, arrangement of chambers and apertures, size are recognized as being of decisive specific or subspecific value. Twenty four phylogenetic lineages were produced by puncuated equilibrium and gradualistic evolutionary trends which observed within 50 benthic foraminiferal species and subspecies belonging to 18 genera throughout the Maastrichtian to Priabonian forms in Tethys as well as one recent species by the present authors and others. In this study, new eight lineages are presented: Clavulina parisiensis d'Orbigny ˃ C. pseudoparisensis Anan, Laevidentalina granti (Plummer) ˃ L. salimi Anan, Lenticulina carinata (Plummer) ˃ L. turbinata (Plummer) ˃ L. chitanii (Yabe and Asano), Percultazonaria ameeri Anan ˃ P. allami Anan, Percultazonaria alii Anan ˃ P. longiscata (Nakkady), Percultazonaria wadiarabensis (Futyan) ˃ P. tuberculata (Plummer), Palmula woodi undulata Nakkady ˃ P. w. woodi Nakkady, Gavelinella b. brotzeni Said and Kenawy ˃ G. brotzeni paleocenica Said and Kenawy. These lineages help, not only to define the major faunal changes at the Cretaceous/Tertiary (K/T) and the Paleocene/Eocene (P/E) boundaries, but also to emphasis the stratigraphic importance of them in different localities in the Tethys.