Britannica Sources used in this answer

When did tetraodontiform fishes evolve?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Scrawled filefish (Aluterus scriptus) — tetraodontiform Scrawled filefish (*Aluterus scriptus*)

Tetraodontiform fishes evolved during the Eocene Period of the Cenozoic Era, approximately 50 million years ago. They are a group of primarily tropical marine fishes closely related to the perciforms, which are considered typical advanced spiny-rayed fishes.1