[Illustration: PLATE 18 _Ptychohyla ignicolor_ (UMMZ 119603). x 2.] =Ptychohyla ignicolor= Duellman _Ptychohyla ignicolor_ Duellman, Uni. Kansas Publ. Mus. Nat. Hist., 13:352-353, pl. 25, fig. 1, April 27, 1961 [Holotype.--UMMZ 119603 from 6 kilometers south of Vista Hermosa, Oaxaca, Mexico; Thomas E. Moore collector]. _Diagnosis._--Diameter of tympanum less than one-half diameter of eye; internarial region flat; 3-7 vomerine teeth; toes one-half webbed; no white spot below eye; no lateral white stripe; in life dorsum green; groin and thighs having bright red flash-colors. _Description._--The following description is based on UMMZ 119603 from 6 kilometers south of Vista Hermosa, Oaxaca, Mexico (Pl. 18). Adult male having a snout-vent length of 30.0 mm.; tibia length, 14.6 mm.; tibia length/snout-vent length, 48.7 per cent; foot length, 12.3 mm.; head length, 9.2 mm.; head length/snout-vent length, 30.7 per cent; head width, 9.3 mm.; head width/snout-vent length, 31.0 per cent; diameter of eye, 3.2 mm.; diameter of tympanum, 1.3 mm.; tympanum/eye, 40.6 per cent. Snout in lateral profile square, and in dorsal profile rounded; canthus pronounced; loreal region slightly concave; lips moderately flaring; top of head flat; nostrils protuberant; internarial distance, 2.8 mm.; internarial region flat; interorbital distance, 3.3 mm., much broader than width of eyelid, 2.8 mm. A heavy dermal fold from posterior corner of eye above tympanum to insertion of forelimb, covering upper edge of tympanum; tympanum elliptical, its greatest diameter equal to its distance from eye. Forearm moderately robust having distinct dermal fold on wrist; pollex moderately enlarged without nuptial spines; second and fourth fingers equal in length; subarticular tubercles round, none is bifid; discs on fingers moderate in size, that on third finger slightly larger than tympanum; no web between first and second fingers; vestige of web between other fingers. Heels overlap when hind limbs adpressed; tibiotarsal articulation extends to anterior corner of eye; no tarsal fold; inner metatarsal tubercle large, flat, and elliptical; outer metatarsal tubercle near inner one and triangular in shape; subarticular tubercles round; length of digits from shortest to longest 1-2-5-3-4; third toe webbed to proximal end of penultimate phalanx; fourth toe webbed to distal part of antepenultimate phalanx; fifth toe webbed to middle of penultimate phalanx; discs on toes smaller than on fingers. Anal opening directed posteriorly at upper edge of thighs; no anal flap; pair of large tubercles below anal opening; small tubercles ventral and lateral to these. Skin of dorsum and ventral surfaces of limbs smooth; that of throat and belly granular. Ventrolateral glands noticeably thickened, extending from axilla nearly to groin and only narrowly separated midventrally on chest; skin of anterior part of chin thickened and glandular.