CHECKLIST OF REPTILES OF MEXICO 95 



Anota Hallowell, Proc. Acad. Nat. Sci. Philadelphia, 1852, p. 182 (type, Anota 



m'calln HaUov/ell). 

 Tapaya Girard (nee Fitzinger), in Wilkes, United States Exploring Expedition, 



Herpetology, 1858, p. 394 (type, Lacerta orbicularis Linnaeus). 

 Doliosaurus Girard, op. cit. p. 407 (type, Phrynosoma platyrhinos Girard). 



Genotype. — Lacerta orbicularis Linnaeus. 



Range. — Nebraska, Kansas, Oklahoma, and Texas westward to the 

 Pacific, northward to British Columbia and Montana, and southward 

 through Mexico to Guatemala. 



Species. — Fifteen, with about 26 forms recognized; 21 occur in 

 Mexico. 



KEY TO MEXICAN SPECIES OF PHRYNOSOMA 



1. Ventral abdominal scales smooth (a few scales may be keeled on breast of 



solare and a few specimens may show faint keeling on some of abdominal 



scales, but this form will have four occipital spines) 6 



Ventral abdominal scales distinctly keeled (rarely indistinctly keeled in 

 cornutum) 2 



2. Horns (or horny spines) present on back of skull 3 



No horns or horny spines on back of skull, the scales that form spines in other 



species are low rounded protuberances; two flaring temporal expansions on 

 back of head separated by a medial notch; lower jaw with great vertical 

 development, the chin shields separated from the infralabials by 4 or 5 

 scale rows; 76 mm ditmarsi (p. 104) 



3. Tail at least half length of body (usually more) ; large species with 2 lateral 



abdominal fringes of soft spines more or less clearly developed 4 



Tail shorter or but little longer than head; smaller species, with 1 series of 

 lateral soft spines 5 



4. Ventral scales large, 30 to 35 across widest part of belly; scales surrounding 



spines of upper lateral fringe very prominent; greater part of gular scales 

 arranged in slightly serrate longitudinal series; 2 very prominent series of 

 large scales widely separated on back; tail about as long as body; length, 



170 mm asio (p. 102) 



Ventral scales smaller, 55 to 70 across widest part of abdomen; 3 temporal and 

 2 occipital spines well developed; 3 brown bands across frontal area; 3 

 radiating lines below eye; rarely ventral keeling is indistinct; length, 140 

 mm comutum (p. 99) 



5. Outer temporal part of skull prolonged backward into a very large "horn" 



several times size of small occipital spines; tail as long as head or slightly 



longer; 9-10 femoral pores taurus (p. 104) 



Outer temporal region not prolonged into a large horn; temporal spines about 

 the same size as occipital spines; tail shorter than head; femoral pores 

 about 10-10 braconnieri (p. 100) 



6. No ear-opening present; tympanum superficial, covered with scales (very 



rarely unsealed in some Mexican specimens of modestum and some 



m'callii 7 



Ear opening present, tympanum usually more or less deeply sunk 10 



7. No lateral fringe of soft spines on sides of abdomen; occipital and temporal 



spines present but rather short; chin shields bordering labial series through- 

 out; greater part of tail very slender and subcylindrical, not gradually 

 tapering; venter white; chin usually speckled; 84 mm._raodesturQ (p. 101) 

 At least 1 series of lateral soft spines 8 



