(From about 2 years ago)

Cope's gray treefrog (Dryophytes chrysoscelis) is a species of treefrog found in the United States and Canada.

It is almost indistinguishable from the gray treefrog (Dryophytes versicolor), and shares much of its geographic range. Both species are variable in color, mottled gray to gray-green, resembling the bark of trees. These are treefrogs of woodland habitats, though they will sometimes travel into more open areas to reach a breeding pond. The only readily noticeable difference between the two species is the mating call — Cope's has a faster-paced and slightly higher-pitched call than D. versicolor.

In addition, D. chrysoscelis is reported to be slightly smaller, more arboreal, and more tolerant of dry conditions than D. versicolor.

https://en.wikipedia.org/wiki/Mexican_alligator_lizard