Males 32-51 mm, females 33-60 mm (Wright and Wright 1949). In general, these frogs have warty skin and prominent adhesive pads on their fingers and toes (Johnson 1987). Their color can vary from green to light green-gray, gray, brown or dark brown (Johnson 1987). Usually, a large irregular star or spot appears on the back (Wright and Wright 1949) A large white spot is always present below each eye (Johnson 1987), although it is less visible and more of an olive color in females (Wright and Wright 1949). The belly is white (Johnson 1987). Males have pale flesh-colored vocal sacs (Wright and Wright 1949). In males, the chin is similar to the belly, with blackish spots (Wright and Wright 1949). In males, the legs are yellow or orange-yellow ventrally. (Johnson 1987), whereas in females, the back of the forelegs, hindlegs and sides are a pale olive gray (Wright and Wright 1949).
The tadpole is approximately 50 mm long, with a long tail. The coloration is scarlet or orange vermilion with black blotches around the edge of the crests (Wright and Wright 1949).
Hyla versicolor is the sibling species of Hyla chrysoscelis (Cope's Gray Treefrog). These two species are indistinguishable based on external morphology (Conant and Collins 1991). Distinction can be made on the basis of the calls, erythrocyte (red blood cell) size (Matson 1990), and chromosomal complement (Conant and Collins 1991). H. versicolor is a genetic tetraploid, whereas H. chrysoscelis is diploid. The precise distribution of each species is not well established (Conant and Collins 1991). In many areas, these two species live sympatrically (occuring together), and if they do, these species may interbreed (Bartlett and Bartlett 1999).
Perhaps the most striking feature of this frog is its ability to change color to match its environment (metachrosis) - a process which usually requires about half an hour (Logier 1952).
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