| Species | Plethodon larselli Burns |
| Family | Plethodontidae (Lungless Salamanders) |
| Status | State Sensitive, USFWS Species of Concern |
| State Rank | S3 |
| Global Rank | G3 |
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A small, striped salamander usually less than 55 mm snout-vent length and 110 mm total length. The color on the sides is black or dark brown with white speckling and there may be flecks of the dorsal stripe color. The white speckling (iridophores) on the sides is dense on the intercostal folds but sparse or absent from the costal grooves. The dorsal stripe is reddish, yellowish, brown or tan, has a scalloped edge and extends to the tip of the tail. In adults and larger juveniles, the dorsal stripe usually stops at the base of the head. Black pigmentation (melanophores) in the middle of the stripe increases with age and is usually arranged in a herringbone pattern. In some adults, the stripe becomes obscured by the large amount of dark pigmentation. The underside is characteristically salmon-pink, red or reddish orange but a small number of individuals have white or gray undersides. The outer toe on the hind foot has only one segment (phalanx). The costal groove count ranges between 14 and16, but is usually 15. Sexual maturity is reached at approximately 40 mm snout-vent length. Coloration in juveniles is similar, but the dorsal stripe is more even-edged with brighter coloration and the red pigmentation on the belly tends to be limited to single or multiple blotches or flecks. There is no free-living larval stage. See Photos Page.
The presence of the nasolabial grooves separates Lungless Salamanders from other types of salamanders. The Woodland Salamanders (Plethodon species) in Washington are similar in general appearance. The following traits distinguish the Larch Mountain Salamander: 1) the underside is pinkish or red, 2) the dorsal stripe has a scalloped edge with dark pigmentation in a herringbone configuration, 3) there is dense white flecking on the intercostal folds but not in the costal grooves, 4) the stripe typically ends at the base of the head and, 5) the outer toe on the hind foot is a quarter the size of the fourth toe. The traits listed above are often lacking, subtle or difficult to see in small juvenile Larch Mountain Salamanders and they can be easily confused with Western Red-backed Salamanders. However, Larch Mountain Salamanders usually have some reddish pigment blotches or flecks on the belly. See Key Features Page.
Most of its life is spent in the subterranean environment and it is surface-active only about 20 to 90 days a year, depending on location and conditions. Surface activity is triggered whenever moisture and temperature regimes are appropriate, primarily in the spring and fall. In the Columbia River Gorge this tends to be mid-February through late-May and in the fall from late September through late-November. In the Cascade Range, the activity period is approximately April through late June and late September to late November. Ideal conditions are when temperatures are between 4 degrees and 14 degrees C and soil is saturated to a depth of about 30 cm. Breeding takes place in the autumn and spring months.
This species is a Washington and Oregon endemic. In Washington, the species occurs in the Wes and East Cascades Ecoregions. The main distribution is along a 58-km stretch of the Columbia River Gorge with additional, isolated populations in the Cascade Range. They have been documented in Clark, Skamania, Lewis, King, Klickitat and Kittitas Counties. Population distribution within the range is patchy. See Distribution Map.
For information on the complete range of this species, see NatureServe Explorer.
Larch Mountain Salamanders are associated with talus, scree, gravelly soils and other areas of accumulated rock where interstitial spaces exist between the rock and soil. Steep slopes are also an important habitat feature. They inhabit a diverse range of forested and non-forested habitats. Occupied rocky substrates in non-forested areas are usually north facing and nonvascular plants, especially mosses, dominate the ground cover. In some areas of the Cascade Mountains, Larch Mountain Salamanders inhabit old-growth coniferous forests without significant exposed rocky areas. They also inhabit lava tubes in the Mount St. Helens vicinity. In all of these habitats, important microhabitats include woody debris, leaf litter and rocks.
The status is based on the small range, low number of documented populations, restricted habitat types occupied by this species, and the extinction risk to populations when their habitat is altered.
Additional inventory to precisely determine the species' range is needed. Information is also needed on life history, reproductive biology, and seasonal habitat use across the species' range.
Any ground-disturbing activity or land use that changes the moisture regimes and permeability of inhabited rocky substrates, such as overstory tree removal and gravel removal, may threaten populations. Chemical applications (i.e., herbicides, pesticides, fertilizers) may affect Larch Mountain Salamanders directly due to toxicity or indirectly due to loss of prey-base.
Aubry et al. (1987), Brodie (1970), Crisafulli (1999), Herrigton & Larsen (1987), Petranka (1998), Trippe et al. (2001).
Personal communications: Charlie Crisafulli
Hallock, L.A. and McAllister, K.R. 2005. Larch Mountain Salamander. Washington Herp Atlas. http://www1.dnr.wa.gov/nhp/refdesk/herp/