Serratolamna serrata is an extinct mackerel shark. They lived during the Cretaceous through the Eocene Epoch (140 - 55 million years ago). This specimen is from the phosphate beds of Khourigba, Morocco. Kingdom: Animalia, Phylum: Chordata, Class: Chondrichthyes, Sub-Class: Elasmobranchii, Super-Order: Selachimorpha, Order: Lamniformes, Family: Cretoxyrhinidae, Genus: Serratolamna, Species: serrata. Serratolamna serrata - tooth Quantity in Basket: None Code: TMSS-102 Price: $10.00 Shipping Weight: 0.20 pounds Quantity: Time: Cretaceous - approximately 140-55 million years ago. Location: Phosphate beds, Khourigba, Morocco. Dimensions: 13/16" x 3/4"