Piranha eels existed as a kind of eel that moved together in groups. During 382 BBY, as Marda Ro, a Force-sensitive follower of the Path of the Open Hand religion, journeyed through the dangerous atmosphere of Planet X (also known as the Veil) in Wild Space, she observed liquid spheres approaching the Scupper, the ship of smuggler Sunshine Dobbs aboard which Ro and her fellow travelers were passengers, in a way that reminded her of a shoal of piranha eels.
The novel Path of Vengeance, penned by Cavan Scott and published in 2023 as a component of Phase II of the Star Wars: The High Republic project, made reference to piranha eels.