page_title: Cretalamna
section_title: Dentition
hierarchical_section_title: Cretalamna / Biology / Dentition
caption_attribution_description: English: Fossil teeth of Cretolamna biauriculata from Khouribga (Morocco)
context_page_description: Cretalamna is a genus of extinct otodontid shark lived about 103 to 46 million years ago from the Late Cretaceous to Eocene epochs. It is considered by many to be the ancestor of the largest sharks to have ever lived, Carcharocles angustidens, and Carcharocles megalodon.
context_section_description: Cretalamna teeth are distinguished by a broad triangular cusp and two lateral cusplets. The cutting edges of the teeth are razor-like, while the sides have a smooth surface. Teeth symmetry is variable; some have exact bilateral symmetry whereas others have high asymmetry. Adjacent teeth do not overlap.
  The exact dentition of Cretalamna is uncertain due to poor fossil representation. Traditionally, most reconstructions of its dentition were constructed from individual shed teeth. Based on a specimen of C. hattini (LACM 128126), the dentition of the shark follows a lamnoid pattern with at least fifteen upper tooth rows and eight lower tooth rows on each side of the jaw. The upper tooth rows contain, from front to back: two symphysial, two anterior, one intermediate, and ten lateral tooth rows. The lower tooth rows contain: two anterior, one intermediate, and five lateral tooth rows. This is given in the dental formula  , constructed in a 2007 study of LACM 128126 by paleontologist Kenshu Shimada. It is possible that Cretalamna contained more than two symphysial tooth rows, as the related Cretoxyrhina mantelli possessed four upper symphysial tooth rows.
caption: Fossil teeth of C. biauriculata from Khouribga (Morocco)
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