n rounded elevations between somewhat
larger, round inner nares; openings to vocal sac large, one
situated along posterior margin of each mandibular ramus.

PLATE 25

[Illustration: FIG. 1. Paratype of _Ptychohyla ignicolor_
(UMMZ 119602). x 3.]

[Illustration: FIG. 2. Holotype of _Ptychohyla chamulae_
(KU 58063). x 3.]

Color (in alcohol) dull brown above with irregular dark
brown blotches; dorsal surfaces of limbs brown with narrow
darker brown transverse bars; posterior surfaces of thighs
cream-color with brown spots and mottling; groin and dorsal
surfaces of first and second toes white; belly
cream-colored; glandular areas orange-brown; chest and chin
having black spots. Ventral surfaces of hind limbs and first
toes cream-colored; undersides of other toes and soles of
feet brown.

Color (in life) uniform bright green above; venter pale
creamy yellow; anterior and posterior surfaces of thighs,
ventral surfaces of shanks, anterior surfaces of tarsi and
upper proximal surfaces of first three toes red; iris pale
golden color.

The paratype is an adult male, having a snout-vent length of
26.3 mm., and agrees with the holotype in proportions. The
ventrolateral glands are less extensive and the chin less
spotted than in the holotype.

_Comparisons_: Both _Ptychohyla schmidtorum_ and the species
described below differ from _P. ignicolor_ in lacking red
flash-colors and in having a white spot below the eye.
_Ptychohyla ignicolor_ also differs in having a small
tympanum. As stated above, these species can be
distinguished from the rest of the genus by the absence of a
tarsal fold and absence of horny nuptial spines in breeding
males.

_Remarks_: The holotype was found on a moss-covered log over
a stream in dense cloud forest by day. The paratype was
calling at night from a low herb at the edge of a small
stream in the cloud forest. Nearby a _Ptychohyla
leonhard-schultzei_ was calling.

Along two cascading mountain streams in cloud forest on the northern
slopes of the Mesa Central in central Chiapas numerous specimens of a
distinctive species of _Ptychohyla_ were found in association with two
species of _Hyla_ and two of _Plectrohyla_. The first specimen of this
new species of _Ptychohyla_ was discovered by Dale L. Hoyt, who found
the frog on a rock