Bela Tyken was a Melthusian captain who first encountered the rare space anomaly which came to be known as a Tyken's Rift sometime before 2367.
When Tyken and his crew were trapped in the rift, his analysis determined that a massive energy release might overload and dislocate the anomaly. Utilizing his cargo of anicium and yurium, he was able to detonate the explosion and escape through the ruptured center of the rift.
Unlike a similar case experienced aboard the starships USS Brattain and USS Enterprise in 2367, there were no reports of behavioral changes in his crew. (TNG: "Night Terrors")
This character was only mentioned in dialogue.