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Fossil Species of Florida

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Amphibia, Lissamphibia, Caudata, Sirenidae

SIREN LACERTINA LINNAEUS, 1765

Common Name: greater siren


Alternate Scientific Name: none


Source of Species Name: Siren lacertina was named in the 13th edition of Linneaus' Systema Nature. The species name is derived from the Latin word lacerta, which means lizard.


Age Range: early Pleistocene (late Blancan) to present, about 2.5 million years ago to the present.


Florida Fossil Occurrences:

Florida map with occurrences indicated

Figure 1. Map of Florida, with black circles indicating counties where fossils of Siren lacertina have been found (the circles do not indicate a specific location within the county where the fossils were found, and some counties may have two or more different locations producing this species).


Florida Fossil Sites with Siren lacertina:
Alachua County—Arredondo 2A; Haile 1A; Hornsby Springs
Columbia County—Ichetucknee River; Ichetucknee River 2B; Ichetucknee River 3B; Santa Fe River 6
Hillsborough County—Leisey Shell Pit 2
Indian River County—Vero Site
Manatee County—Brandenton Field
Marion County—Reddick 1B
Pinellas County—Maximo Moorings; St. Petersburg Times; Seminole Field; Zeta Pond Site
Polk County—Palmetto Mine Pleistocene Bog
Sarasota County—Macasphalt Shell Pit 1
St. Johns County—Wilson Quarry
Taylor County?Aucilla River 1A; Aucilla River 3J

Overall Geographic Range: Fossils identified as Siren lacertina have only been found in Florida (Harper, 1935; Goin and Auffenburg, 1959). However, living members of the species are found from southern Maryland through South Florida west to southern Alabama (Conant and Collins, 1998; Holman 2006).

Comments: Siren lacertina is a large, extant salamander in the family Sirenidae. Live individuals may be recognized by their olive to light gray, elongate, snake-like bodies, short external gills, lack of hind limbs, and an average length of 20-30 in. or 51-76 cm, although the record length is about 98 cm (Conant and Collins, 1998). They are darker dorsally and have miniscule eyes, four fingers, and a variable number (31- 37) of costal grooves on their side (Cope, 1889). They closely resemble a second extant species of Siren, Siren intermedia, which is smaller in size (up to 68.6 cm) and has fewer costal grooves (Conan and Collins, 1998; Holman 2006). More information on the ecology and biology of living individuals can be found at this web site.


Skull of Amphicyon longiramus

Figure 2. UF 21008, a vertebra of Siren lacertina in anterior (right) and posterior (left) views from the Ichetucknee River, Columbia Co., FL. Note both ends of the centrum are concave, forming what is termed an amphicoelous vertebra.



canine teeth of Amphicyon

Figure 3. Vertebra of Siren lacertina in dorsal (right), ventral (middle), and lateral (left) views (same specimen as Fig. 2). Note the V-shaped edge of the neural spine in the dorsal view and the foramen at the base of the transverse process in the lateral view.


Fossil specimens assigned to this species consist solely of vertebrae, which have amphicoelous centra (both ends of the vertebral body or centrum are concave), strong neural spines which are ?V?-shaped when looked at from behind, and with ?well-developed central keels with large foramina on either side? (Meylan, 1995). They can be differentiated from the vertebrae of members of the closely related sirenid genus Pseudobranchus by looking at several other features of the zygopophyseal ridge and the vertebral body (Goin and Auffenburg, 1955). However, the identification of fossil sirenid vertebrae in Florida to Siren lacertina is almost entirely based on their large size. The vertebrae of Siren lacertina and Siren intermedia are practically identical except that the former is much larger (Goin and Auffenburg, 1955; Meylan 1995). Goin and Auffenburg (1955) attributed the large size of Siren lacertina to a trend generally seen in the Pleistocene of Florida where many groups of animals evolved forms much larger than their Miocene predecessors.

The oldest examples of fossils of Siren lacertina come from the late Blancan in the Macasphalt Shell Pit 1 (Sarasota County) and the St. Petersburg Times site (Pinellas County). The Leisey Shell Pit 2 record might be Irvingtonian, but that pit also commonly produced Rancholabrean specimens, and the specimen in question lacks stratigraphic data. All of the other Florida fossils sites with Siren lacertina are securely dated in the Rancholabrean Land Mammal Age.

Most fossils of Siren lacertina have been found at sites with other aquatic vertebrates such as fish, frogs, or other aquatic salamanders. Presumably their ecologic preferences have remained constant over time, at least through the Pleistocene.

View an image gallery of this species.[Not yet available!]


Scientific Publications and Other References Cited:

Conant, R., and J. T. Collins. 1998. A Field Guide to Reptiles and Amphibians. Houghton Mifflin Company, Boston, 592 p.

Cope, E. D. 1889. The Batrachia of North America. Bulletin of the U.S. National Museum 34:1-525. http://books.google.com/books/download/The_Batrachia_of_North_America.pdf?id=wMFOAAAAMAAJ&output=pdf&sig=ACfU3U3cKb0lwC8iDz7hbujCPrRZ5IAcRA

Goin, C. J., and W. Auffenburg. 1955. The fossil salamanders of the family Sirenidae. Bulletin of the Museum of Comparative Zoology 113(7):497-514. http://biodiversitylibrary.org/page/2781927

Holman, J. A. 2006. Fossil Salamanders of North America. Indiana University Press, Bloomington, 239 p.

Meylan, P. A. 1995. Pleistocene amphibians and reptiles from the Leisey Shell Pit, Hillsbourough County, Florida. Bulletin of the Florida Museum of Natural History 1(9):273-297. http://ufdcweb1.uflib.ufl.edu/UF00095791/00001/285j

Ultsch, G.R. 1973. Observations on the life history of Siren lacertina. Herpetologica 29(4):304-305. http://www.jstor.org/stable/3891567


Original Author(s): Arianna Harrington

Original Completion Date: November 30, 2012

Editor(s) Name(s): Richard C. Hulbert Jr.

Last Up-dated On: April 30, 2013

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.

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