Katanna Lex

Katanna Lex was a Trill Starfleet officer during the 24th century. She was the host of the Lex symbiont immediately prior to Jonozia Lex. 

She was an Academy classmate of Jean-Luc Picard and Alyson Foxton, the latter of whom also served as her First Officer during her command of the USS Reliant (NCC-44686) in the 2350s and 2360s. (U.F.O.)

During the Federation-Cardassian War she was captured by Cardassian forces and held in a Cardassian prison. Jonozia Lex later compared the experience with the brutality Adrik Thosen inflicted on Elizabeth Lisley, commenting that the torture Katanna had experienced at the hands of the Cardassians "came nowhere near what he saw in that room". (Nuclear Time)

In 2367 she died from injuries sustained at the Battle of Wolf 359, after escaping the destruction of her ship. (The Journey)