HERPETOLOGY OF ZUNI MOUNTAINS — GEHLBACH 



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Bernalillo County (UNMCV 1138-61) are very light with little hint of 

 spotting. It is apparent that larvae from shallow, weU-illuminated 

 pools are lighter in color than those from deeper, darker environments. 

 Very large larvae are usually greenish, olive, or brown, with widely 

 spaced black spots. They often lack light and dark mottling and a 

 lateral light line. Coues (1875, p. 633) described this "Siredon" or 

 axolotl coloration in specimens from Jacob's Well, Apache County, 

 Arizona, and from San Francisco Mountain. 



The nrnnber of gill rakers provides structural evidence that larvae 

 from the Colorado Plateau, southern Arizona, Wyoming, and other 

 localities in New Mexico are very similar (table 3). Northern Arizona 

 specimens have somewhat fewer gill rakers, but this appears to be local 

 variation since larvae from Telluride, Colorado, resemble them yet 

 are geographically closer to populations with more rakers, e.g., Molas 

 Lake. Larvae from Michigan (A. t. tigrinum) and San Luis Potosi, 

 Mexico (A. f. velasci), also have fewer gill rakers and approach the 

 reduced number characteristic of Ambystoma rosaceum in this respect. 

 Further study of larval characters should aid in clarifying the status 

 of other subspecies of tiger salamanders. 



Table 3. — Frequency distribution of gill rakers on the anterior face of the third gill 

 arch in larvae {35-65 mm. snout-vent) of Ambystoma tigrinum and A. rosaceum 



In the Zunis, larvae and adults of A. t. nebulosum usually were found 

 in temporary potholes and canyon-bottom pools. Larvae were col- 

 lected in cattle tanks on Mount Taylor in 1959, and S. W. Woodhouse 

 (1854, p. 35) reported Siredon lichenoides (=large larvae of A. tigrinum) 

 in a spring near the Zuni Pueblo. Although suitable habitats were 

 investigated repeatedly throughout the present study, larvae were not 

 discovered until July 1957, when the unusually heavy rainfall produced 



