Rylen Talris was a tall, male Trill joined to the Talris symbiont sometime in the mid-24th century. In the 2370s, he served his people as a senator within the Trill Senate and also held a seat on the Trill Symbiosis Commission.
Senator Talris was a popular public figure among the Trill population, especially the unjoined due to his sympathy and attention to their problems. He was affable and unruffled when dealing with difficult situations, and appeared well-dressed. Talris had known Taulin Cyl for many years.
Talris was in the Trill Senate Tower during the neo-Purist instigated riots in early-October 2376. He greeted General Taulin Cyl, Hiziki Gard, Lieutenant Ezri Dax and Doctor Julian Bashir when they arrived, and dismissed Cyl's request that he get to safety in the tower's upper levels. Instead, he intended to address the crowds outside from the speaker's platform. Cyl relented and assigned three armed guards to accompany him, unaware that the guards were actually neo-Purist terrorists.
Shortly afterwards, Cyl and Dax discovered that the senate had been infiltrated by the neo-Purists and found that Rylen Talris - host and symbiont - had been killed. (DS9 - Worlds of DS9 novel: Trill: Unjoined)