الفهرس 
Material and methodOnly 14 pages are availabe for public view
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Abstract
The main aim of this thesis is to study the elasmobranchs (sharks and batoids) fossil remains from the Mokattamian Stage (middle-late Eocene) of Egypt. There are very few contributions to this subject until today.
In an attempt to reduce this gap in our knowledge, the following steps have been achieved in the present study:
1) Identification of species based on large assemblages of fossil teeth and taking into consideration the morphological differences that may be due to different positions on the jaws, to sexual dimorphism, etc. The study of the teeth of extant genera and species was helpful in this approach.
2) Updating the specific and generic allocation of the various taxa that have been identified.
3) Temporal distribution of the studied fossils.
The material of this study is based on the collection of Prof. Amin Strougo housed in the Geology Department, Ain Shams University. This rich collection has been gathered over many years from different localities. The stratigraphic position of each studied species and the formation (s) from which it came are as follows:
1- Greater Cairo, east and west of the Nile: Elasmobranch fossils in these localities have been collected from the Qurn, Wadi Garawi and Wadi Hof Formations, spanning levels MK7 to MK12. In the eastern Greater Cairo, two sections yielded elasmobranch fossil remains: east ElBasatin and Gebel Nasuri sections. While in the western side of the Nile the fossil remains have been collected from Gebel Gibli ElAhram section, south of the Sphinx and Darb ElFayum section at the west side of the Cairo-Fayum road.
2- Fayum area: Fossil remains have been collected from the Muweilih Formation up to the Qasr ElSagha Formation spanning from level MK3 to MK12. The material was collected from various sections: Mingar Shinnara, Wadi Muweilih, south of Qusûr ElArab, Wadi Hitan, Mingar ElRayan, with a total number of twenty-three identified species.
3- Bahariya Oasis: The material was collected from two outcrops:
(a) ElGedida iron mine at the northeastern corner of the Bahariya Depression; from the glauconitic sandstone bed (level MK3) located erosively above the iron ore.
(b) The northern plateau of the oasis at km 55 to the north of the ElGedida-Cairo asphalt road. The yielding horizons of this area are the ElGharaq Formation (level MK7) and the Qasr ElSagha Formation (level MK11).
4- Beni Suef area: Some shark teeth were collected from the Beni Suef Formation (level MK7) of Gebel Tarboul and from the Wadi Garawi Formation (level MK8) of Gebel Homret Shaiboun.
5- Maghagha area: Gebel Qarara section yielded several shark teeth from the Midawara Formation (levels MK4 and MK5).
6- Minia area: Basal part of the Samalut Formation (level MK1) of the Sawada section.
7- North Eastern Desert: from the Wadi Hof Formation (level MK11) of Gebel Iweibid section
8- West central Sinai: from the Darat Formation (level MK3) of Wadi Matulla.
In addition to this material, there was a small lot of shark teeth in Strougo’s collection donated by Prof. Abdel Galil Hewaidy, of Al Azhar University. These teeth were collected by the latter from the Midra Shale of Qatar. The Midra Shale of Qatar is generally considered to be of middle Eocene (Lutetian) age, and used in this present study for comparison.
The main conclusions achieved through this study can be summarized in the following points.
1) Thirty-two species belonging to twenty-five genera and fourteen families (twenty species of selachians belong to sixteen genera and twelve species of batoids belong to nine genera) have been identified, illustrated, and fully discussed.
2) A more “biological” approach of some species has been realized, based on the study of a large number of specimens collected from various stratigraphic levels and different localities, and by taking into consideration difference in tooth morphology that may be due to different positions on the jaws, to sexual dimorphism, etc. The study of the teeth of extant genera and species has been very enlightening in this approach.
3) All the species in the studied collection contain a full set of information concerning the locality from which they came, the formation from which they were collected, and their precise stratigraphic level within the different intervals of the Mokattamian Stage (MK1-MK12) following the latest scheme proposed by Strougo (2008). As a result, several species appear to be characteristic of specific horizons and, hence, could be used in the future in regional biostratigraphic correlation.
4) The average size of Misrichthys stromeri Case & Cappetta, 1990 seems to be age dependent, younger populations generally being larger in size. If this trend is confirmed by future studies, it may be used to separate specifically older populations from younger ones.
5) The species Ginglymostoma angolense Dartevelle & Casier, 1943 is reported for the first time in the Egyptian Eocene, and from the middle Eocene of Qatar (see below point #6).
6) The species “Carcharias” koerti (Stromer, 1910), Moerigaleus vitreodon Underwood &Ward, 2011, Physogaleus aff. tertius (Winkler, 1874), and Rhizoprionodon sp. are reported for the first time from the middle Eocene of Qatar (based on material in Strougo’s collection coming from this country).
7) A new species has been identified in the middle Eocene (possibly level MK3) of ElGedida iron mine, in the Bahariya Oasis. It has been recently published (Salame & Asan, 2019) under the name of Odontorhytis bahariensis and reincorporated in this study.