Jang Si Naran was a Thallonian male and a Starfleet Ensign serving aboard Deep Space 9 in the 2370s. Si Naran was slender, with a goatee and a braided length of hair on the back of his otherwise bald head.
In 2376, Naran and Ezri Dax informed Commander Elias Vaughn that Taran'atar had definitely left the space station. Before he left on the USS Defiant to pursue the Jem'Hadar, Vaughn ordered Naran to keep a sensor lock on the USS Euphrates which Taran'atar had commandeered. (DS9 novel: Warpath)