Skin is dorsally nearly smooth, with only sparsely scattered minute, blunt tubercles between the shoulder and sacral regions.

The dorsum is tan with small, dark brown spots forming an interrupted X-like marking.

A faint lighter line runs from the snout through the upper eyelid to the supratympanic fold and continues posteriorly, separating the tan dorsum and the darker flank.

At the type locality, specimens were found at night perching on twigs of short shrubs along a dried stream.

Despite surveys during all seasons, G. seesom were only encountered in early January, a period with little rain and low temperatures.