[1] 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.

[3] This is the norm for fossilized Chondrichthyans, since a shark's skeleton is made of cartilage and soft tissues don't preserve well.

However, some researchers have proffered Macrorhizodus, Isurolamna, and Cretalamna as candidates for genera ancestral to Carcharodon, taxa ranging from the Eocene to the Cretaceous.

[3] Study of white shark taxonomy is complicated by nomenclature and repeated taxonomic reassignments of various species.

It lived in the Miocene and Pliocene period and was a possible ancestor of the great white shark (Carcharodon carcharias).