Eurycea bislineata complex, a group of five closely related, yet distinct species of salamanders with overlapping ranges: Junaluska salamanders ( ), Blue Ridge two-lined salamanders (Eurycea wilderae), northern two-lined salamanders (Eurycea bislineata), southern two-lined salamanders (Eurycea cirrigera), and brown-backed salamanders (Eurycea aquatica). The exact relationship among species in the complex is unclear, but research suggests brown-backed salamanders (Eurycea aquatica) are the sister species to . (Bonett, et al., 2009; Kozak, et al., 2006; Ryan, 1998), the Junaluska salamander, is found only in the upper Tennessee River drainage in western North Carolina and southeastern Tennessee. This area includes the Cheoah River drainage (Graham County, North Carolina), tributaries of the Little Tennessee River in Great Smoky Mountains National Park, and sections of the Tellico River (Monroe County, Tennessee). The Junaluska salamander is part of the
Junaluska salamanders are most commonly found at relatively low elevations (below 700 meters) in wide-basin streams containing sand-gravel substrate with many large rocks. Specific activity patterns of are not known. However, it is believed that adult Junaluska salamanders have seasonal activity patterns similar to other sympatric Eurycea species. In these species, adults spend cooler months and mating times in streams and warmer months in the surrounding forest. (Chattin, et al., 2007; Ratzlaff, 1999; Ryan and Sever, 2005)
Junaluska salamanders have brownish, mottled dorsal sides, with broken dorsolateral stripes resembling wavy lines or blotches. The ventral surface is lighter than the dorsum, and is usually some variation of yellow. There are 14 costal grooves. The tail is relatively short and averages 50% of total body length. The limbs are relatively long. Average body size of adult females is 43 mm snout-vent length (SVL) and maximum sizes for males and females are 49 and 47 mm SVL, respectively. The average size of adult males is not available, as few have been collected. Sexually active males can be distinguished from females by the presence of cirri, wider heads, mental glands, and enlarged premaxillary teeth. Males posses simple testes. Larvae are olive green to brown on the dorsum, cream colored on the venter, and possess a narrow dark line beginning on the snout and extending posteriorly through the center of the eye which terminates in two concentrated patches of melanophores on the cheeks. When viewed laterally, larvae have a mottled appearance with melanophore concentrations increasing towards the tail. Mass of members of the E. bislineata complex has not been reported. No specific information on metabolic rates is available for members of the E. bislineata complex. As a lungless member of the family Plethodontidae, Junaluska salamanders likely have low metabolic rates and low energy requirements (Bruce 2005). (Bruce, 1982; Bruce, 2005; Ryan and Sever, 2005; Ryan, 1997; Ryan, 1998; Sever, 1983; Sever, 1989; Sever, et al., 1976)
Junaluska salamanders resemble other sympatric species within the E. bislineata (northern two-lined salamander) complex. They have an indistinct color pattern and wavy lines and blotches instead of the dark dorsolateral lines characteristic of Blue Ridge two-lined salamanders (Eurycea wilderae). Coloration of adults is sufficient to differentiate between species. Junaluska salamanders possess relatively longer forelimbs than northern two-lined salamanders (Eurycea bislineata), as well as a shorter tail and more prevomerine teeth. Junaluska salamander larvae are indistinguishable from Blue Ridge two-lined salamanders (Eurycea wilderae) at very early ages, with differentiating characteristics not developing until SVL of at least 13.4 mm is reached. Intensity and pattern of pigmentation can be used to distinguish between the larvae of the two when they are of similar size and age. Cheek patterns on larval Blue Ridge two-lined salamanders (Eurycea wilderae), when present, are more diffuse than Junaluska salamanders. Larval Blue Ridge two-lined salamanders (Eurycea wilderae) commonly have iridiophores located on the venter whereas larvae of Junaluska salamanders rarely do. Junaluska salamander larvae grow more rapidly and have a greater size at metamorphism than northern two-lined salamanders (Eurycea bislineata). (Ryan and Sever, 2005; Ryan, 1997; Ryan, 1998; Sever, 1983; Sever, 1989; Sever, et al., 1976)
Embryonic development lasts approximately one month. Hatchlings are 7 to 8 mm in snout to vent length. Larvae metamorphose after 2 or 3 years, at a size of 34 to 40 mm snout to vent length, depending on environmental conditions. Knowledge of reproduction comes from the Santeetlah Creek population in North Carolina and laboratory experiments from specimens taken from this area. It is possible that time to metamorphose varies in different populations. (Bruce, 1982; Ryan, 1997; Ryan, 1998)
The specific mating system of Junaluska salamanders is not known. However, closely related southern two lined salamanders (Eurycea cirrigera) exhibits polygynandry. (Bruce, 1982; Matthes, 2010; Ryan and Sever, 2005; Ryan, 1998)
Reproduction and oviposition of Junaluska salamanders occurs in water. Breeding likely occurs from fall to early spring. Eggs are attached to the bottoms of rocks in moderate stream flow, generally in depths of less than one meter. Egg clutches average 30 to 49 eggs and are attended by adults. Egg deposition occurs in spring around May. First reproduction likely occurs at the end of the third year in Junaluska salamanders. The breeding interval is not known. However, southern two lined salamanders (Eurycea cirrigera), a closely related species in the complex, breeds annually. (Bruce, 2005; Matthes, 2010; Ryan and Sever, 2005; Ryan, 1998)
No specific information regarding the lifespan of Junaluska salamanders has been reported. However, the closely related species, Blue Ridge two lined salamanders (Eurycea wilderae) have an average generation time of 4.4 years and few individuals survived more than 5 years. Junaluska salamanders are prohibited as pets throughout much of their range, so no information on captive lifespan is available. Other members in the genus Eurycea have recorded captive lifespans of over 9 years. (Bruce, 1988; Chattin, et al., 2007; Matthes, 2010; Nelson, 2003; Ratzlaff, 1999; Sever, 2005)
Courtship and other behaviors have not been observed in Junaluska salamanders, but are assumed to be similar to other members of the E. bislineata complex. In the sister species, brown-backed salamanders (Eurycea aquatica), males exhibit mate guarding behavior, but not territoriality. Courtship is elaborate among related species in the E. bislineata complex. It involves a tail-straddling walk in which the female follows the male with her snout rested on the base of the males tail near the caudal glands. The walk begins by the male nudging the females head, with the female responding by approaching or moving away from the male. If the male is successful, the female follows him until a spermatophore is deposited on the substrate, which she then picks up and uses to fertilize her eggs. Secretions from the caudal gland are used to keep the female following the male which increases the likelihood of successful spermatophore transfer. (Alcorn, et al., 2014; Kozak, 2003; Vitt and Caldwell, 2014)
Specific activity patterns of Junaluska salamanders are not known. However, it is believed that adult Junaluska salamanders have seasonal activity patterns similar to other sympatric Eurycea species. In these species, adults spend cooler months and mating times in streams, and warmer months in the surrounding forest. Home range size for Junaluska salamanders is not known. However, closely related northern two-lined salamanders (Eurycea bislineata) was found to utilize 14 square meters over an 11 month period, but the size of its home range was not determined. (Ashton Jr. and Ashton, 1978; Ryan and Sever, 2005)
Communication methods have not been studied in Junaluska salamanders, but related species within the E. bislineata complex use chemical signals that are released by various glands, and detected by cirri protruding from the chin. There are generally two types of courtship glands: mental glands located on the head and caudal glands at the base of the tail. Courtship behavior of closely related southern two-lined salamanders (Eurycea cirrigera) and Blue Ridge two lined salamanders (Eurycea wilderae) also includes cheek rubbing, tail undulating, and head sliding. (Alcorn, et al., 2014; Kozak, 2003; Vitt and Caldwell, 2014)
The diet of Junaluska salamanders has not been reported, but likely consists of invertebrates. The diet of the sister species, brown backed salamanders (Eurycea aquatica), includes a variety of insects, arthropods, worms, and isopods. Larvae of Junaluska salamanders raised in laboratory settings were fed insect larvae. (Ryan and Sever, 2005; Sever, 2005)
Predators of Junaluska salamanders are not known, but likely include fish, small mammals, birds, and anthropogenic (collection for use as fish bait) threats experienced by closely related members of the E. bislineata complex. Some members of the genus Eurycea have glands in the tail that produce chemicals used to deter predators. Specific anti predator behavior of Junaluska salamanders have not been recorded, but other members of the E. bislineata complex exhibit a defensive posture when confronted by predators. (Ryan and Sever, 2005; Sever, 2005; Vitt and Caldwell, 2014)
Specific ecosystem effects of Junaluska salamanders are not known. Salamanders in general benefit ecosystems by providing direct and indirect influences on detritus cycling, connecting matter and energy between aquatic and terrestrial environments, contributing to soil dynamics through burrows, and by providing energy and nutrients to higher trophic levels. Salamanders can also be used as indicators of ecosystem health. (Davic and Welsh Jr., 2004)
Junaluska salamanders have no positive economic impact on humans.
There are no adverse impacts of Junaluska salamanders on humans.
Populations of Junaluska salamanders are small and isolated, which increases the likelihood of localized extinctions. They are considered vulnerable by the IUCN.
Noel Lyon (author), Texas A&M University, Jessica Light (editor), Texas A&M University, Tanya Dewey (editor), University of Michigan-Ann Arbor.
living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
an animal that mainly eats meat
uses smells or other chemicals to communicate
active at dawn and dusk
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
union of egg and spermatozoan
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
mainly lives in water that is not salty.
having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.
An animal that eats mainly insects or spiders.
fertilization takes place within the female's body
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.
having the capacity to move from one place to another.
This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.
the area in which the animal is naturally found, the region in which it is endemic.
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
chemicals released into air or water that are detected by and responded to by other animals of the same species
the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.
Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).
breeding is confined to a particular season
remains in the same area
digs and breaks up soil so air and water can get in
uses touch to communicate
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
Living on the ground.
movements of a hard surface that are produced by animals as signals to others
uses sight to communicate
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