Description
The Dusky Salamander can be tan to dark brown in colour and be either
plain or mottled. Juveniles have five to eight pairs of round spots on
the back. A key diagnostic feature of the dusky salamanders is the pale
line that runs from the eye diagonally to the jaw. It has a sharply keeled
triangular tail. Including the tail, the Dusky Salamander can grow to over
14 cm in length.
Confusing Species
The most similar looking species is the Northern
Two-lined Salamander, which is a similar background colour, but has
two stripes down its back. However, in some individuals the line is broken
or faint. It lacks the diagonal eye line. In Qu�bec, there is also the
Mountain Dusky Salamander, which varies greatly
in colour pattern but usually has a stripe down its back marked with V-shapes.
It also has the line from eye to jaw, but the shape of the tail is rounded
rather than triangular.
Distribution
The Dusky Salamander is widespread in Qu�bec south of the St Lawrence
and in southern New Brunswick. It is limited to only one site in Ontario
between Lakes Erie and Ontario. In the United States, the Dusky Salamander
can be found as far south as Louisiana.
Habitat
The preferred habitat for the Dusky Salamander is spring-fed rocky creeks
in forested areas. They are rarely found far from water.
Reproduction
The Dusky Salamander breeds in spring. The female lays a cluster of
up to 30 eggs that somewhat resembles a bunch of grapes. The eggs are laid
near water beneath rocks, in rotting logs, or in sphagnum moss. The female
remains with the eggs until they hatch in two to three months. At that
time, the larvae are roughly 1.5 cm in length. The larvae transform in
about a year at 4 cm in length. It takes another three to four years for
the salamanders to mature.
Natural history
Dusky Salamanders are frequently found under rocks next to creeks. They
eat a variety of insects and other invertebrates. During the winter, they
can remain active in the water.
Conservation Concerns
Although there is no evidence of declines in this species, it has a
very restricted distribution and has been recommended for designation as
an endangered species in Ontario.
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