Salamanders and Newts
Salamanders, newts and caecilians (a legless, salamander-type animal)
all belong in the order Amphibia along with frogs and toads, ancestors
of the first aquatic vertebrates to begin to colonize that other
earthly environment - land. Comprising a mere 350 species out of
the 4000 or so known species of amphibians, salamanders and newts
are found only in the Americas and in the temperate zones of Northern
Africa, Asia and Europe.
There is little distinction between the amphibians known as "newt"
and "salamander." What is called a salamander in the Americas
may well be called a newt in Europe. Some apply the name "salamander"
to the fully aquatic and fully terrestrial animals, while applying
the name "newt" to those animals that live on land from
late summer through winter, entering water to breed in the spring.
For the sake of simplicity, we well refer to all types as "salamanders."
Often mistaken for lizards, salamanders (sometimes called "sallies"
by people who raise them) have soft, moist skin covering their long
bodies and even longer tails. They have no scales, claws or external
ear openings. The larva are sometimes confused with the frog tadpoles,
but their heads do not get as large as the tadpoles. They have feather
gill structures present just behind the head on the sides of the
neck area, and their front legs develop first; frogs lack the external
gill structures, and their hind legs erupt before their forelegs.
The majority of the salamanders and their larva are carnivorous,
taking in insects, small invertebrates; the large adults eat fish,
frogs and other salamanders. Secretive, essentially voiceless animals,
they are chiefly nocturnal, hiding under fallen logs and damp leaf
litter during the daylight hours. The larvae begin feeding immediately
after hatching, devouring tiny aquatic animals.
There are three types of salamanders: totally aquatic, semi-aquatic,
and completely terrestrial; some of the latter are arboreal. The
aquatic live out their complete life cycles in the water. The semi-aquatic
live primarily on land, hibernating during the winter, and enter
the water as breeding season begins. After mating and egging is
complete, they once again return to land. The terrestrial salamanders
spend their entire lives on land, rarely entering the water though
they are never far from it. Early born young will reach the terrestrial
stage by the end of the year; late born young usually overwinter
as larvae, metamorphosing the following spring.
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