A visiting butterfly is a visitor from a past event and will come into your forest to give you the chance to buy an egg of this species! It will also allow you to use it's special ability so you can test it out! If you purchase the egg, the butterfly will leave and move onto the next forest! So make sure you use the ability before you choose to lay the egg!
You can purchase visiting butterfly eggs for Flutterbucks, and the price varies on the rarity of the butterfly! You can not use "Lay an Egg for Free" abilities on Special Visitors.
Please note: when purchasing a special visitor you will not purchase the fully completed butterfly. You will be purchasing one egg (Level 1), and you will need to use Flutterbucks or abilities to lay the further 4 eggs to hatch and fuse together, completing the species.