The slither eel was an animal lifeform native to the Ferenginar. The hide of the slither eel was used to make boots, and the raising of these eels was a lucrative business in the Ferengi Alliance. However, the overly honest business practices of Drek led to a massive run on eel hide, and eventually to the extinction of the slither eel shortly before the year 9315 of the Ferengi calendar. (DS9 reference: Legends of the Ferengi)