Mount Lyell salamander

The Mount Lyell salamander is endemic to the western slopes of the central and southern Sierra Nevada of California, United States, encompassing a range of approximately 7,002 mi almost entirely within national forests.^[1][2][4][5] They can be found in a range of microhabitats, such as rock exposures, talus, and rock fissures, and under rocks or in caves or crevices. They tend to be found on surface levels in the presence of water sources that provide adamant moisture and mist.^[6] Since this species does not have lungs, they don’t need to be close to large, running water sources in order to survive.^[7] For example, these salamanders can receive their water intake simply by nestling under flat rocks and dirt where snowmelt seeps in or sprays from waterfalls.^[7][6] Its altitudinal range is 1,220–3,670 m (4,000–12,040 ft) above sea level. This high- elevation habitat lacks natural resources such as vegetation, but also thus provides an isolated range for these salamanders.^[8] It is estimated that, between their northern and southern populations, there exist 440,000 to 750,000 Hydromantes platcyephalus.^[5]

The salamander has a flat, slender body with short legs and a tail.^[3] They are a small salamander species—growing to just under 5 inches at full maturity.^[7] Though almost always having a dark back, its appearance can change significantly as the species matures. They commonly share the trait of having a speckled backside.^[3] Young salamanders are observed to be covered in green and yellow spots, while more mature specimens are commonly a mixture of gray and brown with silvery spots on their bellies.^[8] However, the species varies visually in color and has been observed to resemble their surroundings when found.^[4]

While specifics are not known, it is believed the Mount Lyell salamander females lay 6-14 eggs in deep rock crevices during the fall, which they guard until hatching in spring or early summer.^[5][8] The salamander also tends to seek out moist areas within these crevices during the end of winter due to snow melting away, and with it, their natural cover.^[6] The salamanders may take up around 2-3 years to mature and live for up to 20.^[5]

It is believed that predators of the Mount Lyell salamanders include birds, snakes, and mammals that typically feed on similar species.^[5] The most common prey of the salamander include small invertebrates, such as centipedes, spiders, termites and other organisms commonly found under cover objects like rocks and leaves.^[6]

Unlike most other salamanders, which are non-surface dwelling, the Mount Lyell Salamander is nocturnal and most commonly inhabits the surface, particularly during periods of rainfall. The species will only seek out deep rock fissures and other moist crevices during the winter.^[6] In addition, the salamander will raise its head and tail when faced with danger and simultaneously lean its body downwards, likely as an intimidation tactic to appear larger. The salamander also relies on its webbed toes and stocky tail when scaling down slopes, using the suction on their toes and the friction from dragging their tail on surfaces to gain stability and safely move.^[8] The salamander is also unlike most others for its lack of lungs, as well as its natural sticky toxin that can be found on its skin and cause a temporary blindness if it makes contact with human eyes.^[3]

When threatened, the species maintains a coiled position for longer than other salamanders so that, when dropped onto their naturally steep habitat, they can effectively and quickly roll away.^[8] The salamander’s isolation from other salamander populations means it has little competition in its range, launching its large tongue to eat small invertebrates.^[5]

• Clark, H.O. Jr., and S.I. Hagen. 2008. Notes on a Mount Lyell Salamander observed near Nevada Falls, Yosemite National Park, California. Sonoran Herpetologist 21:122-123.
• Clark, H.O. Jr., and S.I. Hagen. 2016. Notes on a Mount Lyell Salamander observed near Nevada Falls, Yosemite National Park, California—Revisited ten years later. Sonoran Herpetologist 29:64.