Species (Hyla crucifer) of tree frog found in ponds, marshes, and other damp areas in the U.S. During the breeding season it can be found in woodland ponds; at other times it is seldom seen. It has a high, whistling call and is one of the first frogs to vocalize in spring. It is tiny (only 0.75–1.3 in. or 2–3.5 cm, long) and grayish, tan, or olive-brown, with an X-shaped or irregular brown mark on its back.

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