The Siladians are a species.
Sometime between 2369 and 2374, Vash was accused of stealing artifacts from the Siladian burial moons and had a price put on her head. Vash returned the artifacts but was implicated in having replaced them with forgeries. Vash claimed the Siladians themselves had looted their burial moons and replaced the artifacts with forgeries to keep tourists visiting their space. (DS9 novel: The Fall of Terok Nor)