Comparison with Local Modern Fauna
To our knowledge, intensive surveys of the extant herpeto-fauna in the immediate vicinity of Porcupine Cave have not been conducted. Limited efforts to document extant herpeto-
faunal diversity in the immediate vicinity of the cave were conducted by Robert Finley Jr. and resulted in multiple observations of the tiger salamander Ambystoma tigrinum (including 10 vouchered specimens) and the garter snake Thamnophis elegans (including four vouchered specimens) within a few miles of the cave (all vouchered specimens are deposited in the Biological Survey Collection in the Museum of Southwestern Biology, University of New Mexico; C. Ramotnik, pers. comm., January 2002). Anecdotal observations of "racers" and of small lizards and anurans cannot be confirmed at this time and do not appear to be supported by voucher specimens in collections. Four amphibian species (Ambystoma tigrinum, Bufo boreas, Pseudacris triseriata, and Ranapipiens) are recorded from Park County, and all four are known to occur above 3300 m elevation within the state (Hammerson, 1986, 1999). One other anuran species (Rana sylvatica) lives today in the north-central portion of the state and is known in Colorado from elevations as high as about 2987 m (Hammerson, 1986). The only definitively identified anuran specimen from Porcupine Cave is referred to Pelobatidae, a group represented by four species in the extant Colorado fauna (Hammerson, 1999). None of the four species is reported from Park County, and all occur today at lower elevations than Porcupine Cave (Spea bombifrons has the highest elevational record of the modern species; it reaches elevations up to 2440 m in the San Luis Valley; Hammerson, 1999).
Three extant reptile species also are reported from Park County—Sceloporus undulatus, Thamnophis elegans, and Opheodrys (=Liochlorophis) vernalis—and all are reported from elevations above 2700 m. There are no historical records of Crotalus viridis from Park County, but elsewhere in the state this species ranges up to 2896 m elevation (Hammerson, 1986), nearly the elevation of Porcupine Cave. Apart from Phrynosoma hernandesi, no other reptile species are known to inhabit elevations above 2700 m elevation in Colorado.
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