Northern two-lined salamander | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Amphibia |
Order: | Urodela |
Family: | Plethodontidae |
Genus: | Eurycea |
Species: | E. bislineata |
Binomial name | |
Eurycea bislineata (Green, 1818) | |
Range of E. bislineata | |
Synonyms | |
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The northern two-lined salamander (Eurycea bislineata) is a species of salamander in the family Plethodontidae found in Canada and the United States. [2] Its natural habitats are temperate forests, temperate shrubland, rivers, intermittent rivers, freshwater marshes, freshwater springs, arable land, and urban areas. It is more water-oriented than the related northern redback salamander, and can often be found in and around water such as rain puddles, streams, swamps, and damp stream beds, whereas the northern redback tends to be found in damp ground, but usually not near open water.
The northern two-lined salamander is a small salamander, with adults ranging from 65–120 mm in total length. [3] This salamander is yellow or yellowish-brown, with two black stripes running down the back which tends to break up after the base of the tail. The flanks are mottled grayish or brown. [4] The belly is pale yellowish, nearly transparent. There are four toes on the fore feet and five toes on the hind feet. [5] On the side of the body are 14–16 costal grooves. [3]
This species prefers small rocky streams or seeps in forests, but may occur in moist areas far from running water. [3] Also, some data suggest this species may be found on stony shores of small lakes and rivers. [6] Northern two-lined salamanders are found throughout northeastern North America, ranging from central and southern Quebec, New Brunswick, northeastern Ontario, and the northeastern United States, from central Virginia and Ohio northwards to the Great Lakes. [3] [4] Compared to many other species in the genus Eurycea, E. bislineata has a large geographic distribution. [3]
The reproductive strategy of the northern two-lined salamander begins with an elaborate courtship. It may take place from September (in the southern parts of its range) to May (in the north). [3] Observations of courtship in the species were made based on individuals held in captivity by Noble (1929), and a summary of these observations are: the male becomes restless, as if searching for a female. Upon finding the female, he will lift her by pushing his snout under her cloacal region or chest. The male adopts a distinct posture, bending his body laterally around her snout. The pair may remain in this position for an hour or more. The female eventually slips out of this posture and begins to straddle the male's tail with her fore limbs, while pressing her chin against the base of the male's tail. The male may undulate his tail from side to side in a slow and exaggerated manner, and the female moves her head from side to side, alternately from the male's tail. This tail-straddling walk may last for over an hour, at which point the male deposits a spermatophore, leading the female to walk over it, at which time she may either accept or reject the male's sperm. [7] The spermatophore of this species is described as conical, 2.5 mm in height and with a colorless stalk that tapers towards the tip. [8]
This species exhibits sexual dimorphism in the shape of the premaxillary teeth. The teeth of breeding males are unicuspid and elongated when compared to the shorter bicuspid teeth of the females. [3] These enlarged teeth are used to help abrade the female's skin and introduce the secretions on the males mental gland, found on the chin, into her circulatory system, which stimulates her to mate. [9] Prior to egg laying, the female searches for a suitable oviposition site in the stream. Nest sites are frequently under rocks, sometimes logs, and perhaps vegetation. [3] Research done in the Georgia Piedmont on the closely related E. cirrigera, indicate that 65% of nests found were under cobbles (2.5 to 30 cm), 16% were under boulders (greater that 30 cm), and 19% were under slate tiles (30x30x1 cm), which were added to the stream experimentally. [10] To deposit eggs on the under surface of a rock, the female must flip on her back to make cloacal contact with the substrate. Three minutes is required to lay each egg in this manner, and up to several hours to lay an entire clutch. [3] The eggs, when freshly laid appear white or pale yellowish, and each egg is 2.5–3 mm in diameter and is surrounded by two distinct membranes. [11] Communal nesting in northern two-lined salamanders has been documented on several occasions and localities; New York, [12] [13] in Ontario, [14] and likely in Ohio. [11]
Upon hatching, the gilled larvae are about 10 mm long, and remain in slow-moving pools, or less frequently, hiding in crevices between rocks and boulders in swift-flowing streams. [15] The larvae do not begin feeding until their yolk sacs are reabsorbed, at which point they begin to feed on benthic invertebrates by prowling the bottom of the stream. Typical prey items for northern two-lined salamander larvae include chironomid larvae and other dipteran larvae, stonefly larvae, cladocera, and copepods. [3] Predators of the larvae are many, such as fish, crayfish, and other salamander larvae, such as the larger northern spring salamander (Gyrinophilus porphyriticus). [5] The larval period of E. bislineata is variable depending on latitude. In the southern portion of their range, such as New York, metamorphosis occurs at 50 mm total length or two years old, while further north, such as in Quebec and likely Ontario, metamorphosis takes place at nearly 70 mm total length, or three years old. [16] The larvae over-winter in deeper pools not prone to freezing. [3]
Once the larvae reach their maximum size, metamorphosis occurs. Sexual maturity is reached in this species at three to four years old. [3] The adults and juveniles tend to be restricted to the stream edges, hiding under rocks and other debris during the day. [17] Seasonal migration does occur, but not all individuals undertake them. Research done in Quebec suggests a postbreeding migration into the forest occurs in June. These adult salamanders may move over 100 m from the stream. The second migration is that of the newly metamorphosed juveniles leaving the stream, but they tend to remain closer to it. About 75% of individuals dispersing over 100 m into the forest did not return, and they were believed to have been consumed by predators. The majority of above-ground movements are made after dark and in wet weather. [18] The diets of the adults are more wide-ranging than the larvae because of the amount of habitat that can be exploited, both terrestrial and aquatic. The movements of juveniles and adults usually occurs in the first hour after dark, when they emerge from under their retreats and forage along the stream bank or forest floor. Food items recorded include wood roaches, arachnids, worms, isopods, millipedes, centipedes, beetles, snails, springtails, flies, hymenopterans, sowbugs, midges, mayflies, annelids, stonefly nymphs, caddisfly larvae, thrips and rarely trout fry. [19] [20] [21] Adult population densities are variable by habitat quality. Adults are also territorial, so if resources are scarce, the population is less dense. In some populations, densities are as low as 0.02-0.04 animals/m2. [22] In other areas, localized densities can be as high as 11 individuals /m2. [23] Adults overwinter up to 80 cm deep into the soil of the stream bank in cold climates, but may remain somewhat active in southern regions, and may continue feeding during this period. [3]
Because of its small size and localized distribution around streams, the northern two-lined salamander is preyed upon by a variety of animals. Predators include birds, such as the eastern screech owl (Otus asio), snakes such as the eastern garter snakes (Thamnophis sirtalis) and ringneck snakes (Diadophis punctatus). Other important predators of the northern two-lined salamander larvae are other salamanders, such as the large, stream-dwelling larvae of the northern spring salamander (Gyrinophilus porphyriticus) and the blackbelly salamander (Desmognathus quadramaculatus). [3] Response to a predator is variable in E. bislineata . Some individuals, when confronted with a garter snake, will remain motionless when contacted by the head of the snake, but would engage in a protean flip, where the tail is held over the body when contacted by the snake's tongue. [24] Tail autotomy is common in E. bislineata , as a result of a struggle with a predator. Losing part of the tail increases the likelihood of surviving the encounter with a predator. In some populations, up to 32% of animals had autotomized tails. [3]
The blue-spotted salamander is a mole salamander native to the Great Lakes states and northeastern United States, and parts of Ontario and Quebec in Canada. Their range is known to extend to James Bay to the north, and southeastern Manitoba to the west.
Brook salamanders are a genus, Eurycea, of salamanders native to North America.
The Texas blind salamander is a rare and endangered cave-dwelling troglobite amphibian native to San Marcos, Hays County, Texas, specifically the San Marcos Pool of the Edwards Aquifer. This species resembles the olm, another stygofaunal salamander from Europe. Unlike the olm, this amphibian's body is not as elongated, and also has less reduced digits on its limbs.
The ringed salamander is a species of mole salamander native to hardwood and mixed hardwood-pine forested areas in and around the Ozark Plateau and Ouachita Mountains of Arkansas, Oklahoma, and Missouri. This species of salamander has slander body, small head, and long tail. They are usually found to have various dorsal color from dark gray to dark brown. Various close relatives are found such as marbled salamander and spotted salamander. This species of salamander has cannibal behavior especially those in large body size.
The marbled salamander is a species of mole salamander found in the eastern United States.
Desmognathus fuscus is a species of amphibian in the family Plethodontidae. The species is commonly called the dusky salamander or northern dusky salamander to distinguish it from populations in the southern United States which form several distinct species, the southern dusky salamanders. The northern dusky salamander is the most widespread representative of its genus in Canada. It can be found in eastern North America from extreme eastern Canada in New Brunswick south to South Carolina. The size of the species' total population is unknown, but is assumed to easily exceed 100,000. The species' habitat differs somewhat geographically; dusky salamanders in the northern part of the range prefer rocky woodland streams, seepages, and springs, while those in the south favor floodplains, sloughs, and muddy places along upland streams. They are most common where water is running or trickling. They hide under various objects, such as leaves or rocks, either in or near water. Alternatively, they may enter burrows for protection. The dusky salamander lays its eggs close to water under moss or rocks, in logs, or in stream-bank cavities. The larval stage which follows is normally aquatic.
The ocoee salamander is a species of salamander in the family Plethodontidae. This salamander has a variety of colors and patterns, and got its name from Tennessee state wildflower. Its natural habitats are temperate forests, rivers, intermittent rivers, freshwater springs and wet rocks in mountainous areas of the Southeastern United States. It was first described by Nicholls in 1949. They are territorial and feed on small invertebrates. It is widely distributed in the southeastern United States and is listed as "Least Concern" by the International Union for Conservation of Nature.
The pygmy salamander is a species of salamander in the family Plethodontidae. It is endemic to the United States in the southern Appalachians in North Carolina and Tennessee. Desmognathus wrighti is a member of the family Plethodontidae and is commonly known as the pygmy salamander. As the name suggest the pygmy salamander is the smallest of the nineteen species in the genus Desmognathus. D. wrighti undergoes direct development and does not have a free-living larval stage. Only two other taxa in Desmognathus, D. aeneus and D. organi, exhibit direct development along with the pygmy salamander. In the genus Desmognathus, body size, habitat preferences, and patterns used by males during courtship are quite variable. D. wrighti courtship is noted by the male biting and seizing its partner in order to provide them with a chemical stimulus. The pygmy salamander can be found in the southern Appalachians of the United States in western North Carolina and eastern Tennessee. Geographical distribution of the Desmognathus wrighti is fragmented and the highest abundance of the species can be found at high elevations in spruce and fir tree forest.
The southern two-lined salamander is a species of salamander in the family Plethodontidae, endemic to the United States. Its natural habitats are temperate forests, rivers, intermittent rivers, swamps, and freshwater springs.
The three-lined salamander is a species of salamander in the family Plethodontidae. It is endemic to the south-eastern United States. This species was classified as a sub-species of long tailed salamanders until DNA sequencing revealed that there was no hybridization between the two species. Like other Plethodontidae species, E. guttolineata captures prey via tongue projection.
The Junaluska salamander is a species of lungless salamander native to the south-eastern United States. It was first described by David M. Sever, Harold M. Dundee, and Charles D. Sullivan who found the species in the range from the Cheoah River, Santeetlah Creek, and Tululah Creek in Graham County of North Carolina. Adults of this species can be found near large, rocky streams and on rainy nights on roads in the areas specified. The salamander is characterized by brownish-yellow coloration with a series of small dots along the body and a robust build compared to the other salamanders in Eurycea. The Junaluska salamander's breeding habits tend to be in large streams where the eggs are laid and attached to the bottom of rocks in the streams where they are found. According to the overall conservation listing for IUCN, this species is listed as Vulnerable. Conservation acts are important in both North Carolina and Eastern Tennessee, since the population of this species in each state is so small.
The Blue Ridge two-lined salamander is a species of salamander in the family Plethodontidae, endemic to the United States. This species is found in the southern Appalachian Mountains, mostly south of Virginia. To the north is a similar salamander, Eurycea bislineata, or the northern two-lined salamander. Its genus, Eurycea contains 33 species and includes taxa that have either a metamorphic life cycle or larval-form paedomorphosis. In species that metamorphose, there can be within-and among-population variation in larval life-history characteristics, e.g., duration of the larval period and size at metamorphosis. Intraspecific geographic variation in species of Eurycea has been attributed to several factors: temperature, stream order and productivity of the larval habitat.
The spring salamander is a species of salamander in the family Plethodontidae. It is found in Canada and the United States. The genus, Gyrinophilus, means "tadpole lover" and refers to the long period of time it spends as a gilled larva before maturing. The specific epithet, porphyriticus, is Latin from Greek, meaning the color of porphyry, a purple stone, and this salamander has also been called the purple salamander.
The mud salamander is a bright red salamander of the family Plethodontidae. It is found in streams, seeps and swamps and underneath logs, rocks and leaves. It is endemic to the eastern half of the United States with one isolated population in central Mississippi. Mud salamanders are rarely seen plethodontids that inhabit muddy wetland and riparian habitats. Mud salamanders don’t generally live above 700 meters in elevation in the Appalachian Mountains, resulting in two geographically isolated populations. Mud salamanders have short stocky bodies ranging from 7.5 to 16 cm long. Body color ranges with age and locality. There are four subspecies in the mud salamander complex, namely the Gulf Coast mud salamander, rusty mud salamander, Midland mud salamander and the eastern mud salamander. Mud salamanders are ectothermic, meaning that they cannot control their body temperature and it fluctuates with the temperature. The mud salamander is readily confused with two other species, the red salamander and the spring salamander.
The red salamander is a species of salamander in the family (Plethodontidae) endemic to the eastern United States. Its skin is orange/red with random black spots. Its habitats are temperate forests, small creeks, ponds, forests, temperate shrubland, rivers, intermittent rivers, freshwater, trees springs. Overall this species is common and widespread, but locally it has declined because of habitat loss and it is considered threatened in Indiana and New York. Red salamanders eat insects, earthworms, spiders, small crustaceans, snails, and smaller salamanders. To eat, they extend their tongue to capture prey on the tip of it and retract it back into their mouths. The red salamander, as a member of the family Plethodontidae lacks lungs and respires through its skin.
The green salamander is a species of lungless salamander in the family Plethodontidae. It and the Hickory Nut Gorge green salamander are the only currently-described members of the genus Aneides that inhabit any areas in the eastern half of United States. Rarely seen in the field, the green salamander is an extremely habitat-specific species that is seldom found away from its preferred surroundings: moist, shaded rock crevices. Green salamanders have one of the most specialized niches of any salamander.
The spotted-tail or spotted-tailed salamander is a species of brook salamander in the family Plethodontidae. This species is, somewhat vaguely, referred to by the common name of 'cave salamander'; however, it is not restricted to dwelling inside deep caverns, but is known for inhabiting surface-level, terrestrial, woodland habitats, as well. More often than not, the common name 'cave salamander' refers to the "true" cave salamanders, such as the olm of Europe. It is rarely used to refer to the axolotl, another species which, like the olm, inhabits caves that never see daylight, thus lacking skin pigment and having extremely poor eyesight when compared with the vivid orange and bright-eyed spotted-tail salamander. Additionally, true cave salamanders, including the olm, spend their entire lives as fully-aquatic amphibians, while the spotted-tail salamander is not limited to an exclusively amphibious lifestyle.
The northern pygmy salamander is a terrestrial species of salamander in the family Plethodontidae and genus Desmognathus. Along with the southern pygmy and the seepage salamander, these are some of the smallest salamander species in North America and can be found in higher elevations in the southern Appalachians.
The spotted dusky salamander is a species of salamander in the family Plethodontidae. It is endemic to the United States.