Taulin Kengro was born in the 2320s, eventually becoming the host of the Cyl symbiont, one of whose previous hosts was Neema, daughter of Audrid Dax and Jayvin Vod. (DS9 novel: Unity; DS9 - Worlds of Star Trek: Deep Space Nine novel: Trill: Unjoined)
Like previous Cyl joinings, Neema, Reck and Elista, Taulin Cyl spent a lot of time researching the bluegill parasites that had killed Neema's father and infiltrated Starfleet. He was part of the loose organisation called the Watchers that kept a look-out for the parasites.
In September 2376, Cyl was serving as a military adviser, having taken a leave of absence from the TDM. He was left in charge of sorting out the parasite crisis on Deep Space 9 by Trill ambassador Seljin Gandres. After meeting Ezri Dax, Cyl told her that Neema had married and had two daughters, and lived to be very old, missing Audrid until she died. (DS9 novel: Unity)
Just after his return to Trill, Cyl was dealing with the civil unrest brought about by the Neo-Purist group. While assisting Dax in the Caves of Mak'ala he was caught in the neurogenic radiation wave from the detonation of a nearby bomb. The radiation separated Cyl from Taulin, and as his last act, Taulin Kengro released Cyl into the pools before drowning. (DS9 - Worlds of Star Trek: Deep Space Nine novel: Trill: Unjoined)