A Ligorian mastodon was a large animal which had the ability to camouflage itself.

In 2373, Jadzia Dax compared the Jem'Hadar's tracking of the cloaked USS Defiant through the Badlands by the ionization of its warp engines to the passage of a Ligorian mastodon through the forest: it could not be seen, but it made the leaves rustle. (DS9: "Blaze of Glory")

According to the script, the pronunciation for Ligorian was "lih-GOR-ee-an". [1]