Spring peepers (in amplexus)

Spring Peepers are tan or brown in color with a dark cross that roughly forms an X on their dorsa (thus the Latin name crucifer, meaning cross-bearer, though sometimes the marking may be indistinct. They have a body length between less than an 1 inch to 1.5 inches and a weight between 0.11 ounces to 0.18 ounces.
The species have large toe pads for climbing, although they are more at home amid the loose debris of the forest floor.
The color variations of the P. crucifer are mostly tan, brown, olive green, and gray. Females are lighter-colored, while males are slightly smaller and usually have dark throats. This frog has a vocal sac located by its throat, which expands and deflates like a balloon to create a short and distinct peeping sound. Only males have the ability to make this loud high-pitched noise, and they use it to attract mates.
Spring Peepers primarily live in forests and regenerating woodlands near ephemeral or semi-permanent wetlands. The amphibious species requires marshes, ponds, or swamp regions in order to support the aquatic environment the eggs and tadpoles need.
In the northern reaches of their range, Spring Peepers must frequently endure occasional periods of subfreezing temperatures during the breeding season. The species can tolerate freezing of some of its body fluids, and undergoes hibernation under logs or behind loose bark on trees. It is capable of surviving temperatures as low as -8°C. This species frequently occurs in breeding aggregations of several hundred individuals, and commonly breeds in many small wetlands, including swamps, temporary pools and disturbed habitats such as farm ponds and borrow pits.