The tree frogs of the _Hyla rubra_ group are abundant and form a conspicuous element of the Neotropical frog fauna. Representatives of the group occur from lowland México to Argentina; the greatest diversity is reached in the lowlands of southeastern Brazil (Cochran, 1955). The group apparently originated in South America; the endemic Central American species evolved from stocks that invaded Middle America after the closure of the Colombian Portal in the late Pliocene.

Dunn (1933) partially defined the _rubra_ group as it occurs in Central America. Cope (1865, 1876, 1887), Brocchi (1881), Boulenger (1882), Günther (1901), Noble (1918), Kellogg (1932), Dunn and Emlen (1932), Stuart (1935), and Gaige (1936) dealt with the Middle American species now considered to make up the _rubra_ group. More recently, Taylor (1952, 1958), Fouquette (1958), Starrett (1960), and Duellman (1960, 1963, 1966a) studied aspects of the taxonomy and biology of the species of this group. The five species of the _rubra_ group in Central America have received ten different names. One species, _Hyla staufferi_, has received five names (two subspecies are recognized herein). _Hyla boulengeri_ was named in the genus _Scytopis_, but the type species of _Scytopis_ is a member of the genus _Phrynohyas_ Fitzinger, 1843 (Duellman, 1956.)