Achatinidae are a family of African snails, many large and contain the largest species of land snail on earth. Achatina achatina can grow to 300mm! Some species have become so invasive that they have become part of the familiar creatures that even the native people can identify.
I remember going searching for native snails in my country and when I asked the native people have they seen any snails, they always point out Achatina fulica! In fact, many people in my country thinks they are a native species or have only seen this species of snail before in their life! Amazing!