Identification
Adults are small, yellow salamanders with a dark stripe down each side of the body. Dorsal color of Southern Two-Lined Salamanders ranges from bright yellow to a dull, brownish yellow. The stripe on each side is wide and black. In-between the stripes, small dark speckling is often present. Ventral coloration is yellowish and lighter towards the center. An adult Southern Two-Lined Salamander can grow to be about 3.5-4 inches in total length.
Eggs are whitish and surrounded by gel membranes. They are most frequently laid under rocks in small streams in single-layered clusters of about 20-100 eggs. Larvae are dark yellow with dark, speckled pigmentation dorsally. They have low fins and transform at around 2-2.5 inches in total length. They have several paired, light-colored spots on the dorsum, distinguishing them from Eurycea longicauda.
The Long-Tailed Salamander (Eurycea longicauda) is generally larger, has dark spots dorsally, and has a longer, compressed tail with dark chevron markings laterally. These two species are often found in the same streams throughout southern and central Indiana. The Cave Salamander (Eurycea lucifuga) is generally larger and orange-red with dark spots dorsally and a longer, rounded tail. These two species are often found in the same streams throughout southern Indiana. The Northern Dusky Salamander (Desmognathus fuscus) is more robust and generally brownish in coloration with a light line running from its eyes to its jaw. These two species are often found in the same streams throughout southern Indiana.
Ecology and Conservation
Southern Two-Lined Salamanders require rocky streams that hold some water throughout the entire year. Sometimes these creeks are concentrated to small pools in the summer. Adults are most frequently flipped under rocks and other cover items in and around these streams, though they will occasionally wander into surrounding forestland. Southern Two-Lined Salamanders are active throughout most of the spring, summer, and fall, and they can occasionally be flipped during mild winter days as well. I have observed these salamanders through most months of the year. Larval Southern Two-Lined Salamanders feed on a variety of aquatic invertebrates, and adults feed primarily on an assortment of terrestrial invertebrates found while foraging around their streams.
Little is known about the breeding of Southern Two-Lined Salamanders. They move towards their streams just prior to breeding, but it is not completely certain whether courtship always occurs on land or occasionally underwater. Breeding of these salamanders reportedly occurs in late March and April. Eggs are laid in within a few weeks, and they hatch in late May or June. Larvae over-winter before completing metamorphosis the next spring or summer.
This is one of the most common and widespread salamanders in the state and is generally abundant in streams where it occurs.
Distribution
This species is found throughout most of the eastern United States east of the Mississippi River south of Michigan and north of peninsular Florida. Southern Two-Lined Salamanders range throughout most of Indiana, with the exception of the northern lakes and swamps and the southwestern floodplains.
Taxonomy
The Southern Two-Lined Salamander (Eurycea cirrigera) has no recognized subspecies. Phylogenetic studies suggest that Indiana's salamanders are more closely related to the Northern Two-Lined Salamander (E. bislineata) than E. cirrigera, but a formal taxonomic revision has not been conducted (Kozak et al. 2006). At one point, the subspecies E. b. rivicola was described from southern Indiana, although few herpetologists use that name today. These salamanders belong to the family Plethodontidae, which is the world's most diverse family of salamanders.
Literature Cited
Conant, R. and J. T . Collins. 1998. Reptiles and Amphibians of Eastern and Central North America. Third Edition, Expanded. Houghton Mifflin, New York, NY.
Kozak, K. H., R. A. Blaine, and A. Larson. 2006. Gene lineages and eastern North American palaeodrainage basins: phylogeography and speciation in salamanders of the Eurycea bislineata species complex. Molecular Ecology 15:191-207.
Minton, S. A. Jr. 2001. Amphibians and Reptiles of Indiana. Indiana Academy of Science, Indianapolis, IN.
Mittleman, M. B. 1949. American Caudata. VI. The races of Eurycea bislineata. Proc. Biol. Soc. Washington, 62:89-96.
Petranka, J. W. 1998. Salamanders of the United States and Canada. Smithsonian Institute Press, Washington D.C.