urs in Colombia,
whereas the other species are known only from Middle America.

_Distribution._--The species of the _Hyla rubra_ group range from the
lowlands of northern Argentina and Bolivia to southern Tamaulipas and
Guerrero, Mexico.

_Comments._--In Central America two subgroups of species can be
recognized. _Hyla boulengeri_ and _H. foliamorta_ are distinctive in
the large size of adults (snout-vent lengths 41-49 mm.); both have
prominent bars on the thighs, a well-defined interorbital triangular
mark, blotches or spots dorsally, and large choanae. _Hyla elaeochroa,_
_H. rubra,_ and _H. staufferi_ are smaller (snout-vent lengths 29-40
mm.); they have the thighs weakly barred or vermiculate anteriorly and
posteriorly or unmarked, an ill-defined interorbital triangular mark,
linear markings dorsally, and small choanae.

Key to Species and Subspecies

1. Larger frogs (males to 49 mm. snout-vent length); thighs
strongly barred; supratympanic fold black; dorsum blotched or
spotted 2

Smaller frogs (males to 40 mm. snout-vent length); thighs weakly
barred or plain; supratympanic fold pale brown; dorsum usually
having linear pattern 3

2. Dorsum tuberculate; snout subacuminate; vocal sac flecked with
brown; tarsal fold rudimentary; web absent between fingers; black
spots absent in scapular region _H. boulengeri_

Dorsum smooth; snout pointed; vocal sac dark gray; tarsal fold
absent; trace of web between fingers; two or more elongate dark
spots in scapular region _H. foliamorta_

3. Snout-vent length more than 30 mm.; tympanum 2/3 to 3/4 diameter
of eye; prevomerine elevations about size of choanae 4

Snout-vent length less than 30 mm.; tympanum less than 1/2 diameter
of eye; prevomerine elevations smaller than choanae 5

4. Thighs mottled posteriorly; discs on fingers about 1/2 size of
tympanum; faint dark line from nostril to eye _H. rubra_

Thighs faintly barred or plain posteriorly; discs on fingers
about size of tympanum; distinct dark line from nostril to eye
_H. elaeochroa_

5. Dorsum brown with irregular dorsolateral stripes and
interrupted paravertebral stripes; two transverse bars on shank