Sabertooth Cave
(= Saber-tooth Cave or Allen Cave)

University of Florida Vertebrate Fossil Locality CI006

Location

Sabertooth Cave is located about 1.2 miles (1.9 km) northwest of Lecanto, between State Highway 44 and County Road 491, Citrus County, Florida. 28.86º N; 82.49º W.

Age

Basis of Age

The co-occurrence of the extant rodents Sigmodon hispidus, Peromyscus gossypinus, Oryzomys palustris, Ochrotomys nuttalli, and Neofiber alleni, indicate a late Rancholabrean age in the chronologic sequence of Florida’s Pleistocene faunas (Morgan and Hulbert, 1996). The age is otherwise not very well constrained within the late Rancholabrean.

Geology

Simpson’s (1928:1) description states “Entrance to [Sabertooth Cave] is through a broad sink terminating in two vertical shafts. Immediately under these the floor of the cave was from 25 to 40 feet below the shaft mouths and there apparently has never been an entrance practicable for large living mammals. On the floor below the sink and in pockets elsewhere was a deposit of red earth or clay in which were found numerous remains of Pleistocene animals, apparently representing a distinctive unit fauna. There also occurred in the cave a younger bed of sand and humus containing no extinct mammals but with numerous remains of the recent white-tailed deer of the region.” Holman (1958) noted that a third, narrow vertical entrance to the cave had opened by 1957 and described the fossil-bearing sediments as “reddish sandy clay” and “well stratified.”

Depositional Environment

Sinkhole/cave complex in a Florida pine flatwood habitat with small ponds (Holman, 1958).

Fossils

The fossils from this cave are housed in the American Museum of Natural History (AMNH) and the Florida Museum of Natural History (FLMNH). A search of the AMNH on-line database for “Allen Cave” in the locality field on 3/30/2015 produced 118 catalog numbers, although more than one specimen could be assigned to a number. The FLMNH collection consists of almost 1200 cataloged specimens, with an estimated additional 1500 uncataloged fossils. The latter consist primarily of partial limb bones, edentulous jaws, and isolated teeth of sigmodontine rodents. The fossil fauna is dominated by the bones and teeth of small mammals, especially rodents, shrews, and moles. The pattern of breakage is suggestive of bones found in owl pellets.

There are some notable differences in the species represented in the two collections. The AMNH has more specimens of larger species (presumably finding most of them), while the FLMNH sample is richer in smaller rodents, including several not found in the AMNH. In the faunal list below, names of species only in the FLMNH sample are followed by a ‘^’. Taxonomic names in the faunal list have been updated to their modern usage from those listed in Simpson (1928), Wetmore (1931), and Holman (1958).

Excavation History and Methods

The first fossil stated to be found at this site was a complete upper canine of the sabertooth cat Smilodon fatalis. This specimen, UF/FGS 1246, was unfortunately lost at the Florida Geological Survey sometime between the publication of Simpson (1928), in which it is figured, and 1970. It was this specimen that gave the cave its name. The alternative name, Allen Cave, refers to the family that owned the cave and surrounding property for many decades. Workers under the supervision of Walter W. Holmes collected at Sabertooth Cave for two months in the spring of 1928. The specimens were rapidly sent to the AMNH, where they were studied by a young George G. Simpson who published them only seven months later in October 1928. The absence of many of the smaller species found by a later party suggests that Holmes’ group did not use screenwashing.

The second and last expedition to Sabertooth Cave occurred on August 9, 1957 and was led by Pierce Brodkorb of the University of Florida Department of Biology and two of his students, including J. Alan Holman who later published on the amphibians and reptiles of the site. Judging by the results, this crew must have hauled out all the fossil-bearing sediment from the cave and later screenwashed it. This method was routinely used by Brodkorb by the late 1950s to recover fossils of small birds after its use had been popularized by Claude Hibbard. Somewhat ironically, the Brodkorb group did not collect any identifiable bird fossils beyond a few partial bones from the bobwhite quail, so they did not add any species to the fauna beyond those described by Wetmore (1931) from the AMNH collection. Because of the long-standing dispute between Brodkorb and the Florida Museum of Natural History, his collection from Sabertooth Cave was given to the Florida Geological Survey (except the birds, which he kept for his own collection). Both groups of specimens eventually made their way to the FLMNH in the end.

Discussion

Sabertooth Cave was the first Florida Pleistocene site found that was numerically dominated by fossils of small vertebrates, and perhaps for that reason, along with no evidence of archaeological specimens, garnered less acclaim than those from Vero, Melbourne, and Seminole Field found during the same era. The site is notable for producing a number of holotype specimens of four species of mammals and one reptile (Simpson, 1928; Brattstrom, 1954). One of Simpson’s species, the pocket gopher Thomomys orientalis is still regarded as valid and since been found at three other sites in Florida ranging from the middle to late Pleistocene (Wilkins, 1985). Today, all species of Thomomys are found west of the Mississippi River. The second new rodent species Simpson named from Sabertooth Cave was the bog lemming Synaptomys australis. It is now known from many sites in Florida as well as several in Georgia. The validity of this species is debated, with some favoring its use while others regard it as a form of the living species Synaptomys cooperi. Simpson’s third new rodent species from Sabertooth Cave was an extinct species of capybara, Hydrochoerus holmesi, that was more similar in size to the living species in South America and much smaller than the larger species in the genus Neochoerus. Simpson’s fourth new mammalian species from Sabertooth Cave was a deer that he thought was related to the living marsh deer (Blastocerus dichotomus) of tropical South America. He based the new species on a single partial mandible and called it Blastocerus extraneus. Not a single additional specimen among the thousands of deer fossils since found in Florida has the characters of the lower premolars found in Simpson’s specimen. While it cannot be positively ruled out as a valid species, the chances are that it is a pathological variant of the common white-taile deer Odocoileus virginianus.

Brattstrom’s (1954) supposed extinct giant rattlesnake (“Crotalus giganteus”), which he named on the basis of two isolated vertebrae from Sabertooth Cave, was later shown by Christman (1977) to just be a moderately large individual of the living eastern diamondback.

Sources


This material is based upon work supported by the National Science Foundation under Grant Number CSBR 1203222, Jonathan Bloch, Principal Investigator. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

Copyright © Florida Museum of Natural History, University of Florida