Heard outside my window tonight, the Northern Spring Peeper! From the Missouri Department of Conservation, Missouri’s Toads and Frogs:
Northern Spring Peeper (Hyla crucifer crucifer)
A small, pinkish, gray or light tan treefrog with a dark x-mark on the back. This species has reduces adhesive toe pads, and spends most of the time on the forest floor or in low shrubbery. Spring peepers average from 3/4 to 1 1/4 inches (19 to 32 mm) in body length. This is a woodland species, living near ponds, streams or swamps where there is thick undergrowth. Spring peepers are active from early spring to late fall, but breed early. Their voices are a true announcement of spring. Small, fishless woodland ponds are required by this amphibian. Their high-pitched, peeping call can be heard on warm spring nights and also during the day in early summer and fall.
It’s too dark to take a photo so I recorded the cute bird-like chirp: Listen