Gray Tree Frog

As the scientific name implies, Gray treefrogs are variable in color owing to their ability to camouflage themselves from gray to green, depending on the substrate they are sitting on. The degree of mottling varies. They can change from nearly black to nearly white. They change color at a slower rate than a chameleon. Dead Gray Treefrogs and ones in unnatural surroundings are predominantly gray. They are relatively small compared to other North American frog species, typically attaining no more than 1.5 to 2 in (3.8 to 5.1 cm). Their skin has a lumpy texture to it, giving them a warty appearance. They are virtually indistinguishable from the Cope's Gray Tree Frog, Hyla chrysoscelis, the only readily noticeable difference being their calls. Cope's Gray Tree Frog has a shorter, faster call.[3] The Gray Treefrog also has an extra set of chromosomes (4N), or 48 in total, and is called Tetraploid Gray Treefrog in scientific circles. The more southerly Cope's Gray Treefrog, or Diploid Gray Treefrog, retained its 2N (24) original chromosome set, so hybridization between these species would not be successful.

Both Hyla chrysoscelis and Hyla versicolor have bright yellow patches on the hind legs, which distinguishes them from other treefrogs, such as Hyla avivoca.[4] The bright patches are normally only visible while the frog is jumping. Both species of Gray Treefrogs are slightly sexually dimorphic. Males have black or gray throats, while the throat of the female is lighter.[5]

Tadpoles have a rounded body (as opposed to the more elongated bodies of stream species) with a high, wide tail that can be colored red if predators are in the system. Metamorphosis can occur in as little as 2 months with optimal conditions. At metamorphosis, the new froglets will almost always turn green for a day or two before changing to the more common gray. Young frogs will also sometimes maintain a light green color and turn gray or darker green after reaching adulthood.