| Salamandrids
are collectively known as the "newts," a term which often
breeds some confusion -- as in "What is the difference between
a salamander and a newt?" The simple answer is nothing: a newt
is simply a specific type of salamander, namely members of the family
Salamandridae. In other words, all newts are salamanders,
but not all salamanders are newts. The newts have an extremely wide
distribution, as they are found in North America, Europe, Asia,
and even portions of northern Africa. They are known for a diversity
of shapes and colors, especially among the males of the European
species during the breeding season. In North America, however, there
are only two genera, and only one of them, Notophthalmus,
is found east of the Mississippi River. What it lacks in diversity,
it makes up for in generality, for Notophthalmus can be
found just about everywhere in eastern North America. The
red-spotted newt is more or less ubiquitous throughout eastern North
America. The usual
life cycle of this species includes three distinct post-hatching
stages: (1) aquatic larva, (2) terrestrial (juvenile) eft, and (3)
aquatic adult. In some populations, larvae may skip metamorphosis
and become paedomorphic adults (like Ambystoma talpoideum),
but this is apparently rare for the newts in the Southeast. Efts
have slightly rough, dry skin and are bright orange or red, and
sometimes even brownish, in color. Once they complete the second
metamorphosis to become aquatic adults, their skin changes from
orange or red to yellowish-green. Nonetheless, they retain small
red spots within black halos found in rows along the sides. These
spots, and the efts coloration, are warnings of toxic skin secretions.
Because of this chemical defense, newts can coexist with fish, which
often eat other salamanders.
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