User blog comment:Adsper/All Possible Mobs/@comment-2804:14D:2A75:8A1C:DCC3:6CEC:6293:2099-20180514003434/@comment-25118285-20180625000634

http://www.elasmo-research.org/education/evolution/carcharodon_vs_carcharocles.htm

This article sums up the Carcharodon/Carcharocles thing. Basically, megalodon used to be lumped into Charcarodon bc it was thought to be an ancestor of the Great White, but it's probably not as closely related, which is why it has it's own genus name (Charcarocles) now.