The Masked Tree Frog is a nocturnal, arboreal species that can be found on the lowlands and foothills of both the pacific and caribbean sides of Costa Rica, although it does not occur on the dry plains of Guanacaste. Its color is variable, however the dark brown patch behind the eye is unmistakable. Their color ranges from entirely tan to entirely green, with intermediate, contrasty patterns in between. When most of their body is tan, it can look very similar to the Cross-banded Tree Frog, however the Cross-banded never has a mask. Their vocal sacs are bilobed, which essentially means that it looks like two vocal sacs, one at each side of the throat.
Another species of nocturnal tree frogs, this one has dark markings that extend from the nose back, surrounding the eye and effectively masking it, which can confuse predators by hiding the eyes of the would-be victim
Looking upwards, this frog shows the light coloration underneath, very different to the green tones on the upperside
Portrait of the frog at it was clinging to a branch covered in moss
Placidly resting over a branch covered in green moss. At the distance one would struggle to spot it
This specific individual is well camouflaged thanks to the patterns in its dorsum
This nocturnal frog looked at the camera briefly. Note the light mask covering the nose and eyelids