Haile 15A

University of Florida Vertebrate Fossil Locality AL032

Location

Location: in an abandoned limestone quarry in western Alachua County about 2.9 miles (4.7 km) northeast of the town of Newberry; 29.7° N, 82.6° W. The site was destroyed by mining operations and no longer exists.

Age

• Early Pleistocene Epoch; early late Blancan land mammal age
• About 2.2 to 2.6 million years old

Basis of Age

Biochronology. The co-occurrence of Nannippus peninsulatus and Sigmodon medius is restricted to the Blancan age. The presence of Paramylodon garbanii rather than Paramylodon harlani is indicative of the early late Blancan interval in Florida, as is the relatively small size of the specimens of Holmesina floridanus (Hulbert, 2010).

Geology

Fossils come from a filled fissure in the Ocala Limestone that was exposed by mining operations. The deposit was about 33 feet (10 m) in length, between 10 and 16 feet (3-5 m) in width, and its depth varied greatly between 6 and 20 feet (2-6 m). Robertson (1976) recognized four sediment types in the deposit, a lowermost very dense brown clay, a coarse mix of gravel and sand, interbedded sands and green clay, and an upper layer of interbedded sand and brown clay. The vertebrate fossils came from the middle two units, with most of the larger bones from the gravelly sand, and most of the more complete turtles and well preseved fish bones from the green clay.

Depositional Environment

Robertson (1976) thought that Haile 15A formed in a forested environment along a spring based on the presence of beaver, gliding squirrel, deer, and tapir. However, the horse Equus is the most common mammal; this along with the presence of cotton rat and the llama Hemiauchenia suggest open, grassland or savanna habitats were also present nearby. The periods of deposition of clay indicate times of a quiet water environment, either a pond, lake, or slow moving river. The abundant fossils of freshwater fish and amphibians, and the pond turtles Deirochelys, Trachemys, and Pseudemys support this.

Fossils

Excavation History and Methods

Haile 15A was found in a quarry owned by Parker Brother’s Limestone Products, Inc. The site was discovered by Phillip Kinsey and Dow Roland in 1964 (Kinsey, 1974; Robertson, 1976). Upon realizing the significance of the find, they donated specimens to the Florida Museum of Natural History, including the holotype of a new species of peccary. The majority of specimens were collected in late 1964 and 1965 by museum field crews composed of then newly arrived curator David Webb, collections assistant Robert Allen, and Webb’s graduate student Jesse Robertson (who eventually went on to describe the Haile 15A mammals for his Ph.D. dissertation). A second major collection of several hundred specimens was made by John Waldrop in the 1960s; they were donated to the Florida Museum of Natural History in 2011. Screenwashing of sediments was done to recover microvertebrates, but no records were kept of the volume or mass of sediment processed by this method. No taphonomic records were made during the excavation. In total, over 2500 identifiable species were collected at this locality.

Discussion

Haile 15A was not the first Blancan locality discovered in Florida, as Santa Fe River 1 preceded it by a few years. But that submerged locality could not be excavated with the precision of a land site, and eventually proved to be chronologically mixed (MacFadden and Hulbert, 2009). So understanding of Florida’s Blancan mammals really began with Haile 15A. With the notable exception of Weaver and Robertson’s (1967) description of Trachemys platymarginata, the diverse assemblage of fish, amphibian, and reptilian fossils from Haile 15A has received little study. Campbell (1976) described the birds from Haile 15A and recognized seven different species from just 10 specimens. Most were living species associated with aquatic habitats, such as pied-billed grebe, green-winged teal, and great egret. One new species of bird was found at Haile 15A, Butorides validipes, an extinct relative of the living green heron. Despite the discovery of many subsequent Blancan-age localities in Florida with large numbers of fossil bird bones, no other records of this species have been found.

In contrast, the mammals of Haile 15A have been relatively well studied. Robertson (1976) described the entire mammalian fauna and named two new species, the pampathere Kraglievichia floridanus and the flying squirrel Cryptopterus webbi. Both species are still regarded as valid, but later research transferred the former to the genus Holmesina (e.g., Edmund, 1987; Hulbert and Morgan, 1993) and the latter to the genus Miopetaurista (Webb et al., 2008). This squirrel is more closely related to the living giant flying squirrels of the Old World than the much smaller species Glaucomys volans that still lives in Florida today. Robertson (1976) also did a detailed description of a small species of mylodont ground sloth, which he referred to a species from Argentina, South America, Glossotherium chapadmalensis. Following Morgan (2008), the small Blancan mylodont from North America is referred to a species named from Mexico, Paramylodon garbanii.

Four species of horses are present at Haile 15A, two three-toed hipparions (Cormohipparion emsliei and Nannippus peninsulatus) and two one-toed horses in the genus Equus. Both hipparions are rare in the fauna. The most common horse is a member of the most primitive subgenus of Equus, Plesippus. Further study is needed to confirm Robertson’s identification of this horse to the species Equus simplicidens from the Blancan of northern Texas and the Great Plains. The Haile 15A sample is relatively smaller than most referred specimens of this species, but the morphology of the teeth is very similar. A second, smaller species of Equus is also present at Haile 15A, but not enough material is present to make a secure identification.

Among the artiodactyls, the most common is the living species of white-tailed deer, Odocoileus virginianus. The fossils of this species at Haile 15A prove that it has lived in Florida for the past 2 to 2.5 million years without significant change. Haile 15A also provides an early record for the llama Hemiauchenia macrocephala, which persisted in Florida until the end of the Pleistocene before its extinction (Webb, 1974). The absence of Palaeolama, the other genus of llama common in the Florida Pleistocene, is significant. It apparently does not appear until the very late Blancan or the very early Irvingtonian. The peccary species Mylohyus floridanus named by Kinsey (1974) from Haile 15A is larger than later Pleistocene specimens of the same genus and it has a longer mandibular symphysis.

Note that in works published prior to 1990, this locality would have been called Haile XVA. The Florida Museum then changed its system for naming such sites and switched from using roman numerals to arabic numerals.

Sources

• Original Author(s):  Rachel E. Narducci
• Original Completion Date:  November 30, 2012
• Editor(s) Name(s): Richard C. Hulbert Jr., Natali Valdes
• Last Updated On: March 4, 2015

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