Late Cretaceous anacoracid sharks (Squalicorax) from Duwi Formation, Gebel Duwi, central Eastern Desert, Egypt: qualitative and quantitative analyses

Abstract

The present work introduces different qualitative and quantitative analyses for the fossil shark teeth of the genus Squalicorax. Forty-five fossil teeth were collected from the Late Cretaceous Duwi Formation, at Gebel Duwi, central Eastern Desert, Egypt. The collected teeth were assigned to four species in genus Squalicorax; S. pristodontus, S. aff. S. crassidens, S. yangaensis, and S. microserratus. For the discrimination among the different Squalicorax species, geometric morphometric analysis was carried out, using ImageJ and MorphoJ software packages. Geometric morphometric analysis included landmark configurations, procrustes superimposition, principle component analysis, and thin-plate spline deformation plots. The quantitative analysis, along with the qualitative examination, provided considerable variations among the different Squalicorax species.