The shell of the Streeler changed colour every hour and was also highly poisonous. These shells had to be handled with protective gloves to prevent one from being harmed. They were useful potion ingredients and employed in the brewing of Doxycide.
- Harry Potter and the Prisoner of Azkaban (First appearance)
- Harry Potter and the Prisoner of Azkaban (video game) (Appears on a Famous Wizard Card)
- Fantastic Beasts and Where to Find Them
- Wonderbook: Book of Potions