Southern Leopard Frog (Lithobates sphenocephalus)
Description and Morphological Characteristics
Southern Leopard Frogs are medium sized frogs, ranging 2 to 3 ½ inches in length. They have a long, narrow pointed head and snout, with a slender body. Males are smaller than females in overall size but have larger, more robust forearms. Color can vary from tan, to different shades of brown, and sometimes green. Individuals are often a combination of colors and most feature round, or longitudinally elongated dark spots across their back. They have light colored dorsolateral ridges which extend continuously to the groin, as well as a light line along the upper jaw. These frogs also have a light-colored spot in the center of the tympanum, and some may have large dark spots on their hind legs that resembles banding.
Range
Native range for this species extends from southeast New York, south through Florida and some of the Keys, and west to east-central Texas. There are some small disjunct populations established in Nebraska and the species has been introduced in the Bahamas.
Habitat and Feeding
These frogs prefer shallower water and can be found in all types of freshwater habitats, even inhabiting slightly brackish waters along the coast. They often venture well away from water sources, so long as there is plenty of moist vegetation for shelter and shade. Southern Leopard Frogs primarily feed on insects and other small invertebrates but they are only limited by the size of their mouth and may also consume smaller frogs.
Breeding and Reproduction
In the northern part of the range, breeding occurs in early spring, but in the southern portion it may occur any day of the year, depending on temperature and moisture. Males call most often while floating in open water, but may also perch on logs or sticks near the water’s edge. Their advertisement calls sound like guttural trills, resembling throaty chuckles, and last less than a second. Trill rates are highly variable, even when listening to a single individual, and can easily be seen and heard in the call structure. Females lay eggs in large masses that attach to emergent vegetation in non-flowing waters that are usually fishless. Clutches may contain as many as 1,500 eggs, and tadpoles hatch within 3-14 days, metamorphosing in 50-75 days. The larval stage may be shortened if there is an imminent threat of the pond drying out.
Conservation
This species is widespread and common throughout most of its range and is the most abundant species of frog in Florida. They are not under federal protection at this time but are included on the Texas Parks and Wildlife Black List.
Pertinent References
Adams, C., and Saenz, D. 2012. Leaf Litter of Invasive Chinese Tallow (Triadica sebifera) Negatively Affects Hatching Success of an Aquatic Breeding Anuran, the Southern Leopard Frog (Lithobates sphenocephalus). Canadian Journal of Zoology 90:991-998.
Butterfield, B. P., Lannoo, M. J., Nanjappa, P. 2005. Southern Leopard Frog. Pp. 586-587 in M. J. Lannoo (Ed.), Amphibian Declines: The Conservation Status of United States Species. University of California Press, USA.
Forstner, J. M., Forstner, M. R. J., and Dixon, J. R. 1998. Ontogenetic Effects on Prey Selection and Food Habits of Two Sympatric East Texas Ranids: the Southern Leopard Frog, Rana sphenocephala, and the Bronze Frog, Rana clamitans clamitans. Herpetological Review 29:208-211.
Saenz, D., Fitzgerald, L.A., Baum, K.A., and Conner, R.N. 2006. Abiotic Correlates of Anuran Calling Phenology: The Importance of Rain, Temperature, and Season. Herpetological Monographs 20:64-82.
Account Author: Hailey Hester
Photos: James Childress
Edited by Christopher Schalk
Southern Leopard Frogs are medium sized frogs, ranging 2 to 3 ½ inches in length. They have a long, narrow pointed head and snout, with a slender body. Males are smaller than females in overall size but have larger, more robust forearms. Color can vary from tan, to different shades of brown, and sometimes green. Individuals are often a combination of colors and most feature round, or longitudinally elongated dark spots across their back. They have light colored dorsolateral ridges which extend continuously to the groin, as well as a light line along the upper jaw. These frogs also have a light-colored spot in the center of the tympanum, and some may have large dark spots on their hind legs that resembles banding.
Range
Native range for this species extends from southeast New York, south through Florida and some of the Keys, and west to east-central Texas. There are some small disjunct populations established in Nebraska and the species has been introduced in the Bahamas.
Habitat and Feeding
These frogs prefer shallower water and can be found in all types of freshwater habitats, even inhabiting slightly brackish waters along the coast. They often venture well away from water sources, so long as there is plenty of moist vegetation for shelter and shade. Southern Leopard Frogs primarily feed on insects and other small invertebrates but they are only limited by the size of their mouth and may also consume smaller frogs.
Breeding and Reproduction
In the northern part of the range, breeding occurs in early spring, but in the southern portion it may occur any day of the year, depending on temperature and moisture. Males call most often while floating in open water, but may also perch on logs or sticks near the water’s edge. Their advertisement calls sound like guttural trills, resembling throaty chuckles, and last less than a second. Trill rates are highly variable, even when listening to a single individual, and can easily be seen and heard in the call structure. Females lay eggs in large masses that attach to emergent vegetation in non-flowing waters that are usually fishless. Clutches may contain as many as 1,500 eggs, and tadpoles hatch within 3-14 days, metamorphosing in 50-75 days. The larval stage may be shortened if there is an imminent threat of the pond drying out.
Conservation
This species is widespread and common throughout most of its range and is the most abundant species of frog in Florida. They are not under federal protection at this time but are included on the Texas Parks and Wildlife Black List.
Pertinent References
Adams, C., and Saenz, D. 2012. Leaf Litter of Invasive Chinese Tallow (Triadica sebifera) Negatively Affects Hatching Success of an Aquatic Breeding Anuran, the Southern Leopard Frog (Lithobates sphenocephalus). Canadian Journal of Zoology 90:991-998.
Butterfield, B. P., Lannoo, M. J., Nanjappa, P. 2005. Southern Leopard Frog. Pp. 586-587 in M. J. Lannoo (Ed.), Amphibian Declines: The Conservation Status of United States Species. University of California Press, USA.
Forstner, J. M., Forstner, M. R. J., and Dixon, J. R. 1998. Ontogenetic Effects on Prey Selection and Food Habits of Two Sympatric East Texas Ranids: the Southern Leopard Frog, Rana sphenocephala, and the Bronze Frog, Rana clamitans clamitans. Herpetological Review 29:208-211.
Saenz, D., Fitzgerald, L.A., Baum, K.A., and Conner, R.N. 2006. Abiotic Correlates of Anuran Calling Phenology: The Importance of Rain, Temperature, and Season. Herpetological Monographs 20:64-82.
Account Author: Hailey Hester
Photos: James Childress
Edited by Christopher Schalk
