Characters of Nummulites multiplicutiospiralis *** the Qarara Formation,Maghagha,Nile Valley,Egypt
Characters of Nummulites multiplicutiospiralis n. sp. from the Qarara Formation, Maghagha, Nile Valley, Egypt作者机构:University of Ain ShamsFaculty of EducationDepartment of Biological&Geological SciencesCairo11341Egypt
出 版 物:《Acta Geologica Sinica(English Edition)》 (地质学报(英文版))
年 卷 期:2021年第95卷第2期
页 面:342-347页
核心收录:
学科分类:070903[理学-古生物学与地层学(含:古人类学)] 0709[理学-地质学] 07[理学]
主 题:invertebrate paleontology foraminifera Nummulites Eocene Nile Valley Egypt
摘 要:Nummulites multiplicutiospiralis *** described and illustrated for both generations from a claystone of Lutetian age in the Middle Eocene Qarara Formation,Maghagha,Nile valley,*** considered to be Nummulites gizehensis,we describe this form as a new species based on diameter of the test and protoconch sizes,septal shape and *** primary feature of this species is spiral multiplication,seen in spiral *** species is also characterized morphologically by lenticular to flat tests with rounded periphery,wrinkled to broadly meandering septal filaments and few granules on the periphery in microspheric *** granules are spirally arranged on the septal filaments in megalospheric *** are longer than high and the spire is *** new taxon belongs to the Nummulites partschi Group,Subgroup *** coiling in the spiral may develop through ontogeny as in ***,the species which was considered to be an index species in the southern Tethys(Boukhary et al.,1982 and Boukhary 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.