The specific name, milii, is in honor of French sailor and naturalist Pierre Bernard Milius.

Its distribution in Western Australia is throughout the southwest, the goldfields, wheatbelt, and Nullarbor regions to the east, and to Shark Bay in the north.

[4] U. milii is found in rocky outcrops and is slightly more cold-tolerant than many other Australian gecko species.

However, it has been shown that this behavior results in a higher aggregate thermal inertia (they stay warmer) than would be found in solitary geckos of this and related kinds in similar circumstances.

[5] In the same source, it was suggested that aggregating for physiological benefits may precede the development of other kinds of social behavior.