Eurycea cirrigera
Southern Two-lined Salamander

Southern two-lined salamanders have a Nearctic distribution. They are found in the eastern and southeastern United States. Southern two-lined salamanders occur from central Indiana and Ohio east to coastal Virginia and south through Kentucky, Tennessee, and Georgia to north Florida and coastal Alabama, Mississippi and Louisiana, west to the Mississippi River. They are replaced in the Smoky Mountains by Eurycea wilderae and in the northeastern United States and southern Canada by Eurycea bislineata, with which it was recently considered conspecific (Jacobs 1987). Some authorities consider these three forms as subspecies of Eurycea bislineata. (Conant and Collins, 1998; Jacobs, 1987; Petranka, 1998)

Southern two-lined salamanders can be found in moist environments, such as creek or river swamps, seepages, and hardwood forests, often hiding underneath leaf litter, vegetation, or logs, and in aquatic habitats where fish are absent or rare. During wet weather, Eurycea cirrigera will often emerge from hiding and move about on the surface in moist woodlands. Southern two-lined salamanders are most abundant in mountainous regions. (Conant and Collins, 1998; Aardema, et al., 1999; Petranka, 1998)

Southern two-lined salamanders are small salamanders, reaching only about 6 to 12 cm total length as adults. Similar to northern two-lined salamanders, however Eurycea cirrigera has 14 costal grooves rather than 15 or 16. The body is yellow orange to rusted color and there are two dark-brown stripes running the length of its body, breaking off into a speckled pattern towards the tail. The back and often the sides are speckled with similar colored dark-brown spots. The tail is fairly long, comprising nearly 50% of its total length.

The name Eurycea cirrigera is derived from the two cirri that grow on males during breeding season. Cirri are small, antennae-like lobes hanging from the salamander's snout. It is thought these cirri are connected with the nasolabial grooves and vomeronasal organ and sensing system and are presumably important for recognizing females and competing males. (Conant and Collins, 1998; Aardema, et al., 1999; Bartlett and Bartlett, 2006; Conant and Collins, 1998; Distler, et al., 1998; Aardema, et al., 1999; Petranka, 1998)

Eggs take about 4 to 10 weeks to hatch, depending on water temperature. Emergence of larvae can be as early as January in the south to May or June farther north. Upon emergence from the egg clutch, larval Eurycea cirrigera are completely aquatic. They are "stream-type" larvae and have reddish colored external gills, are mostly "dusky" gray above, with six to nine pairs of light spots on the sides, and have a large tail fin. Primary food for larvae is taken at the same trophic level as the adults, consisting of copepods, isopods, and chironomids (Pauley and Watson 2009). When larvae are beginning to undergo metamorphosis into the adult form, the characteristic yellowish belly begins to form and the tail fin and gills begin to recede. True adulthood is determined by length rather than age. Generally it takes between 1 and 3 years for Eurycea cirrigera to develop all the key features of an adult; shorter maturation periods occur in the southern part of the range (Jakubanis, Dreslik, and Phillips 2008). (Jakubanis, et al., 2008; Pauley and Watson, 2009; Petranka, 1998)

Depending on local conditions, mating can occur from September through May. Mating can occur in water or on land. Courtship involves nudging and "sniffing" behaviors by the male, and he may use his premaxillary teeth to scratch the female's skin, probably to introduce pheromone secretions from his mental gland (on the chin) into the female's bloodstream. This is eventually followed by the female straddling the male's tail as they walk forward. Fertilization involves the male depositing a spermatophore, which the female picks up with her cloaca; thus fertilization is internal. (Grant, 1955; Petranka, 1998; Weichert, 1945)

Males grow 2 cirri below their snout during mating season, it is expected that this is to sense both mates and competition (Distler et al., 1998) Eggs are deposited from the end of March until May, depending on location. Females generally lay their eggs under rocks, logs, or other shelter, always underwater in a stream or river. Eggs are never laid on terrestrial areas. They generally number from 15 to nearly 100 per nest (Pauley and Watson, 2009; Petranka, 1998). Females guard their nests until the eggs hatch. (Distler, et al., 1998; Pauley and Watson, 2009; Petranka, 1998; Weichert, 1945)

Females must develop and yolk eggs, expend energy during courtship, and then stay with the eggs until hatching. Males expend much energy during courtship and in defending terrestrial territories. (Pauley and Watson, 2009; Petranka, 1998)

Little is known about the maximum or potential lifespan of this salamander in the wild. Related species in this genus are known to have lived over 9 years in captivity. (Petranka, 1998; Slavens and Slavens, 1999)

Southern two-lined salamanders are cryptic, spending most of their time under logs or foliage hiding from their many predators. On damp nights they may emerge and forage on the forest floor. (Conant and Collins, 1998; Grant, 1955; Petranka, 1998; Vernberg, 1953)

In the presence of other males, they are known to be territorial. A territorial male will approach the intruding male, and bump the intruder in with its snout. Occasionally, the defending male will even snap at the intruder, potentially removing its tail (Grant 1955). (Grant, 1955)

These salamanders may hibernate in winter, however movement and feeding during winter months has been noted and the extent of dormancy is undoubtedly related to local and regional conditions. When they hibernate they burrow 20 to 30 cm into the soil (Vernberg 1953). Feeding may occur throughout the year if conditions are suitable. (Vernberg, 1953)

In laboratory settings, a typical movement range of Eurycea cirrigera is between 5 and 6 inches (12.7 to 15.2 cm) from a resting area. In the wild, these salamanders may make seasonal migrations between streams and terrestrial woodland habitat of up to 10 m. (Grant, 1955; Petranka, 1998)

Communication during courtship and territorial encounters is largely tactile and through detection of chemicals (pheromones). Visual signals in the form of posturing are also used. (Grant, 1955; Pauley and Watson, 2009; Petranka, 1998; Weichert, 1945)

Southern two-lined salamanders are opportunistic predators, eating whatever small organisms they encounter, both as aquatic adults and terrestrial adults. This includes crustaceans, mollusks, copepods, and insects. Though their larvae are known to eat other species of salamander larvae, it was recently found that their larval diet primarily consists of chironomids, or midges, which are available year round, in both good and poor water conditions. Petranka (1998) listed the diet of adults as including roaches, spiders, ticks, earthworms, isopods, millipedes, beetles, snails, springtails, flies, and hymenopterans. (Muenz, et al., 2008; Petranka, 1998)

Predators of southern two-lined salamanders include birds, such as thrushes and screech owls, fish (rainbow trout and brook trout), garter and ring-necked snakes, crayfish (in larval stages), and other salamanders (Pauley and Watson 2009). In the presence of black-bellied salamanders (Desmognathus quadramaculatus), southern two-lined salamanders were found to migrate further from stream to drier sites, indicating that this larger species could be a recognized predator (Grover 2000). Eurycea larvae restrict their movements and remain hidden more in the presence of larger larvae in the genus Gyrinophilus. When they are in the presence of garter snakes, adult salamanders are known to use a protean flipping escape, followed by running away (Ducey and Brodie 1983). They will readily autotomize (drop) their tails when attacked by snakes and other predators. (Ducey and Brodie, 1983; Grover, 2000; Pauley and Watson, 2009; Petranka, 1998)

Small plethodontid salamanders have been shown to play a significant part in cycling nutrients between the forest leaf litter community and larger vertebrates, as they can build up large populations and and represent large portions of biomass. Research done on northern two-lined salamanders is undoubtedly relevant to southern two-lined salamanders as well (Burton and Lichens 1975). (Burton and Lichens, 1975; Petranka, 1998)

Because of their small size, southern two-lined salamanders are often used as bait for recreational fishing. Their importance in the forest leaf litter and adjacent aquatic communities may be unappreciated by most humans, but they undoubtedly contribute to healthy forest ecosystems. (Pauley and Watson, 2009; Petranka, 1998)

There are no known adverse effects of Eurycea cirrigera on humans. (Bartlett and Bartlett, 2006; Petranka, 1998)

This species remains relatively common in undisturbed habitats. As with all salamanders, populations may decline or be locally extirpated due to intensive timber harvest, other land use changes, stream pollution and siltation, or changes in soil chemistry due to "acid rain." These salamanders often disappear from urbanized or suburbanized landscapes. (Petranka, 1998)

Southern two-lined salamanders hybridize with other salamanders in the genus Eurycea, such as northern two-Lined salamanders. Additional studies on the extent of hybridization may indicate whether these salamanders should remain a separate species or be reunited with their closest relatives. (Bartlett and Bartlett, 2006; Pauley and Watson, 2009; Petranka, 1998)