Precursors of the Nummulites gizehensis and N. partschi group from Egypt

Characters ofNummulites multiplicutiospiralisn. sp. from the Qarara Formation, Maghagha, Nile Valley, Egypt

“…The multispiral growth in Eocene Nummulites was previously recorded in some species by Wielandt (1991), Boukhary et al (2010) andFerrà ndez-Canadell (2012). This character, and other poorly understood characters such as reflexive coiling and retrogenesis are in need of further investigation in the Nummulites lineages.…”

“…Another distinctive character, reflexive coiling, which reportedly persisted in Nummulites rollandi Ficheur, 1890, as recorded in Tunisia by Schaub (1981) and in Egypt by Boukhary et al (2010), might be phylogenetically controlled. Based on observations from our study and previous reports regarding reflexive coiling, we suggest that spiral multiplication, retrogenesis and reflexive coiling, may be important in phylogeny and deserve much more detailed investigation.…”

“…The new taxon belongs to the Nummulites partschi Group, Subgroup N. gizehensis. Reflexive coiling in the spiral may develop through ontogeny as in N. rollandi, the species which was considered to be an index species in the southern Tethys (Boukhary et al, 1982 andBoukhary et al 2010). The characters of the new species, as well as its retrogenesis and reflexive coiling, should be further studied in general in Nummulites spp., to understand the importance of such characters phylogenetically.…”

“…recorded two subgroups of morphotypes related to the Nummulites gizehensis Group from the Middle Eocene sequence of the Citadel area, east of Cairo, and also from west of the Fayoum depression. Boukhary et al (2010) also studied the Middle Eocene larger foraminifers of the Mokattam Formation exposed at the Citadel section, north of Gebel Mokattam and they also differentiated two additional morphotypes (Nummulites lyelli d'archiac and the Haime (1853) morphotypes 1 and 2), based on the nature of their septa.…”

Biometric analysis ofNummulites bahariyaensisn. sp.(Nummulites partschigroup) from the Bartonian of Bahariya Oasis, Egypt

“…The authors recommend that the only way to emphasise the evolution is to subdivide the spiral into three stages, the inner, the middle and the outer part (Blondeau 1972), and to apply the biometry of all measurable parameters to understand the ontogenetic and phylogenetic changes and study the species in a complete stratigraphic section with respect to their geographic provinces. Said (1951) raised the rank of de La Harpe's races, among them Nummulites champollioni, to specific level and hence should be given the credit for the name (Boukhary et al 2010). The ontogenetic character of the spire in Nummulites farisi is similar to that of Nummulites gizehensis although its phylogeny is still unknown.…”