Carcharodon

Carcharodon (from Ancient Greek κάρχαρος (kárkharos), meaning "sharp, jagged", and ὀδούς (odoús), meaning "tooth", and thus, "sharp tooth/jagged tooth") is a genus of sharks within the family Lamnidae, colloquially called the "white sharks." The only extant member is the great white shark (Carcharodon carcharias). Extinct species include C. hubbelli and C. hastalis. The first appearance of the genus may have been as early as the Early Miocene or Late Oligocene. Carcharocles megalodon is still argued by some paleontologists (e.g. Michael D. Gottfried, Leonard Compagno, and Ewan Fordyce) to be a close relative of Carcharodon carcharias - as well as being in the same genus. When Megalodon belonged to this genus it had the scientific name Carcharodon megalodon. More recently, Megalodon has been assigned by most scientists to either the genus Carcharocles or Otodus.

== Fossil history and evolution == The fossil ancestry of Carcharodon is an active area of research and debate, given the dearth of the fossil record and the incompleteness of found specimens. Most Carcharodon fossil remains of are in the form of teeth, along with some vertebral centra. This is the norm for fossilized Chondrichthyans, since a shark's skeleton is made of cartilage and soft tissues don't preserve well. Thus, assessing relationships between fossil species relies largely on the form of their teeth. This difficulty is compounded by the incomplete fossil record of Lamnids. However, some researchers have proffered Macrorhizodus, Isurolamna, and Cretalamna as candidates for genera ancestral to Carcharodon, taxa ranging from the Eocene to the Cretaceous.