Ruushko-Yorn/Legends

The Ruushko-Yorn were fabled in conspiracy and alien abduction stories in the Galactic Republic.

History
The Ruushko-Yorn inhabited the galaxy of the Yuuzhan Vong, and were considered their erstwhile allies, but were wiped out alongside the Sluggorn and Menoptera when the Yuuzhan Vong turned on them in the first act of the Cremlevian War.

As of the Clone Wars, the Ruushko-Yorn were fabled in HoloNet conspiracy channels, which claimed they would steal children of the Galactic Republic from their beds. They were linked to Extra-galactic abduction stories on the Galactic Rim from holotabloids. Preparing to meet with Chiss ambassadors, Senator Padmé Amidala reminded herself not to compare her guests to such conspiracy stories.

In an alternate universe where Leia Organa Solo was kidnapped and enslaved by Pazda Desilijic Tiure and his children, the Ruushko-Yorn posed a threat to Coruscant and the New Republic. In 21 ABY, Han Solo embarked on a last-ditch effort to recruit Lando Calrissian's Syndicate on Nal Hutta to fight the Ruushko-Yorn before Coruscant could fall to their might.

Behind the scenes
The Ruushko-Yorn were first mentioned in the Legends Alternate Universe erotic fiction "Ku'Nee" by Darty Ridley and Shabby Blue, and were used as an analogue to the Yuuzhan Vong.