Cow Knob Salamander

The Cow Knob salamander is a moderately large plethodontid. The largest recorded length is 17.1 cm (6.7 in), though most adults have a total length smaller than 15.7 cm (6.2 in). Around half of the total length is tail. The base coloration is dark brown or greyish-black. The sides and legs are colored with large white or cream spots, which may extend onto a portion of the belly. The back is typically speckled with smaller and more scattered spots. The species name 'punctatus' ("spotted") is in reference to these dorsal spots. The throat has a light pink or pale coloration which transitions to the grey belly. The white-spotted slimy salamander (Plethodon cylindraceus) is similar in size and color, but differs in many other respects. Plethodon punctatus can differentiated by its more slender build, slightly webbed toes, protuberant eyes, a higher number of costal grooves (usually 17–18), and a lighter throat. It is very similar in appearance to closely related salamanders in the Plethodon wehrlei group, though it is slightly larger and completely lacks distinctive coloration patterns such as red spots, brassy flecks, or large yellow dorsal spots.

Cow Knob salamanders are adapted to live in high-elevation hardwood forests with dense canopy cover and talus. Old-growth forests and hemlock stands are greatly preferred, while young pine monocultures and clearings are avoided. They typically occur at an elevation of 900–1,200 m (3,000–3,900 ft), with some reports as low as 735 m (2,411 ft). They are particularly abundant on north-facing slopes with an ample supply of rocks for cover. Rocks with large gaps underneath are the preferred form of refuge, followed by fallen logs.

The salamanders are most active in the spring (April–June) and fall (September–October), sheltering during the harsher months of the summer and winter. In West Virginia, their peak season extends into the early summer. They forage on cool wet nights, prioritizing the forest floor but also venturing onto trees or rocks. A wide range of small invertebrates are taken as prey. Plethodon punctatus is a host to Cepedietta michiganensis (a ciliate) and Batracholandros magnavulvaris (a nematode), both of which are fairly benign gut parasites common among Appalachian salamanders. Cow Knob salamanders are direct developers, mating via spermatophore in the late winter or early spring. A clutch of 7-16 eggs can be laid every other year, though the precise timing is unknown. Juveniles hatch in the fall and reach sexual maturity within 3 or 4 years, with females maturing later and at a larger body size. This species is not migratory on an individual basis, and most adults have a range of only a few meters throughout their lifetime. Plethodon punctatus coexists alongside the ecologically similar Shenandoah Mountain salamander (Plethodon virginia, previously referred to Plethodon hoffmani). The two species do not show any competitive exclusion, despite P. punctatus juveniles overlapping the size range of P. virginia adults. …