Duellman (1960) placed _Hyla pinorum_ Taylor in the synonymy of _Ptychohyla leonhardschultzei_ Ahl. At that time only the holotype, a female, of _H. pinorum_ was known. In 1964 Kraig Adler and I independently collected frogs and associated tadpoles in Guerrero that subsequently proved to be _Hyla pinorum_ and provided evidence that _Hyla pinorum_ is not conspecific with _Ptychohyla leonhardschultzei_. The specific name _pellita_ is Latin, meaning covered with skin, and is here used in reference to the complete concealment of the tympanum beneath the skin. Hyla siopela new species Plate 18 _Holotype._--Adult male, KU 100981, from a small stream on the west slope of Cofre de Perote, Veracruz, Mexico, elevation 2500-2550 meters; obtained on July 30, 1966, by William E. Duellman. _Paratypes._--KU 100976-80, 100982-5, same locality, date, and collector; KU 105628-9, same locality, obtained on June 18, 1966, by Howard L. Freeman; UIMNH 57687-57701, same locality, obtained on July 30-31, 1964, by Macreay J. Landy and John D. Lynch. _Diagnosis._--A member of the _Hyla bistincta_ group characterized by truncate snout with short rostral keel; fingers having little webbing and bearing large discs; axillary membrane absent; thoracic fold weak; prepollex large, flat, bearing small nuptial spines; vocal slits absent; dorsum green or tan with small irregular dark spots; flanks mottled. _Description of holotype._--Adult male having a snout-vent length of 44.3 mm.; tibia length 21.1 mm., 47.6 per cent of snout-vent length; foot length (measured from proximal edge of inner metatarsal tubercle to tip of longest toe) 20.4 mm., 47.2 per cent of snout-vent length; head length 13.4 mm., 30.2 per cent of snout-vent length; head width 13.7 mm., 30.9 per cent of snout-vent length. Snout in lateral profile truncate, in dorsal profile truncate with weak vertical rostral keel; canthus angular; loreal region slightly concave; lips thick, not flaring; snout short; nostrils barely protuberant, directed dorsolaterally, situated about four-fifths distance from anterior corner of eye to tip of snout; internarial distance 3.6 mm.; internarial area not depressed; top of head slightly convex; interorbital distance 4.9 mm., 35.8 per cent of width of head; width of eyelid 3.5 mm., 26.0 per cent of width of head. Diameter of eye 4.7 mm.; heavy dermal fold curving posteroventrally from posterior corner of eye, covering upper one-third of tympanum, to insertion of arm; tympanum barely distinct, its diameter 2.2 mm., 46.8 per cent that of eye, separated from eye by distance equal to half again diameter of tympanum.