Pleistocene Mammals from the Rock Springs Local Fauna, 



Central Florida 



Kenneth T. Wilkins^ 



Florida State Museum, 

 University of Florida, Gainesville. Florida 3261 1 



ABSTRACT. — Although several of the interesting fossil mammals 

 from Rock Springs, Orange County, Florida, have been mentioned in 

 scientific papers, this is the first comprehensive report of its mammal- 

 ian fauna. The fauna, which evidently accumulated during several 

 intervals of late Pleistocene deposition, consists of at least 27 species, 

 including both marine and terrestrial forms. The faunal composition, 

 coupled with modes of preservation (e.g., a barnacle-encrusted speci- 

 men of a terrestrial species), provides direct evidence of at least one 

 marine transgression (probably corresponding to the Pamlico shore- 

 line) into central peninsular Florida. Two extralimital taxa character- 

 ize the Rock Springs fauna: (1) current affinities of Thomomys sp. 

 (pocket gophers) are with western North America, and (2) Mormoops 

 sp. (leaf-chinned bats) now occur in western North America and the 

 Neotropics. 



INTRODUCTION 



The Rock Springs site in central Florida has yielded an interesting 

 sample of late Pleistocene vetebrate fossils. Although the first collec- 

 tions were made in the 1920s, the first mention of fossil vertebrates from 

 Rock Springs was a list of seven taxa (Gut 1939). Of the five vertebrate 

 classes represented in this fauna, only the avifauna has been comprehen- 

 sively reported (Woolfenden 1959). Auffenberg (1963) included two ser- 

 pent species — Drymarchon corais, an indigo snake, and Crotalus gigan- 

 teus, a large rattlesnake — from Rock Springs in his review of the fossil 

 snakes of Florida. Ray et al. (1963) discussed the presence of Mor- 

 moops megalophylla, a leaf-chinned bat, and Ray (1964) and Gillette 

 (1976) studied a species of small cat, Felis amnicola, from this site. 

 Webb (1974) listed some 17 mammalian species from the Rock Springs 

 site. 



This paper presents the first comprehensive compilation of the 

 Rock Springs mammalian fauna. Re-examination of all available fossil 

 material, including a new collection made in 1982, reveals 27 mammal- 

 ian taxa, some 14 of which are extinct (Table 1). Ten species in the 

 Rock Springs local fauna presently occur in Florida. Because one spe- 

 cies was not identifiable to genus (i.e., the large felid), its current status 



' Present Address: Department of Biology, Baylor University, Waco, Texas 76798. 



Brimleyana No.9:69-82. June 1983. 69 



