The family Hylidae is found throughout the Americas, Europe and northern Asia and Africa. This family is most diversely represented in tropical South America. The Pacific Northwest is represented by two genera, Hyla and Pseudacris (Nussbaum et al. 1983). Idaho has two species in this family, Hyla regilla and Pseudacris maculata. The Pacific Treefrog is referred to by some scientists as the Pacific Chorus Frog (Pseudacris regilla). There currently seems to be no major consensus as to which name is most appropriate. The Boreal Chorus Frog (Pseudacris maculata) is a new name, formerly being a subspecies (P. triseriata maculata).
All members of the family have intercalary cartilage
between the ultimate and penultimate phalanges (Nussbaum et al. 1983) which, with arboreal species having developed toe pads, may allow better adhesion . Most species in the family have long slender limbs (which, again may facilitate an arboreal lifestyle).