The elderly Trill who hosts the Bix symbiont in 3191 and has waited for someone to solve its riddle so that the memories of an earlier host, Jinaal, can pass on a clue.
Kalzara Bix appears in Jinaal. Discovery's hunt for the Progenitors' technology leads to Trill, because one of the scientists who hid it eight centuries earlier was a joined Trill named Jinaal Bix. The symbiont has been kept alive well beyond a normal span.
Kalzara greets Burnham and Book with a question and, satisfied with the answer, agrees to a zhian'tara, the rite in which a past host's consciousness is placed for a time in another body. Guardian Xi conducts it, and Hugh Culber volunteers to receive Jinaal.
While Jinaal, in Culber's body, leads the officers into the canyons to test them, Kalzara remains at the caves. The rite leaves her and the ageing symbiont at peace.