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View Full Version : What's the difference between a newt and a salamander?


sherri
16th February 2007, 13:16
Sorry about the stupid question, but I do not know

TJ
16th February 2007, 17:30
A newt is a salamander but a salamander is not necessarily a newt, just like a toad is a frog but all frogs are not toads. Specifically, a newt is a salamander that's a member of the family Salamandridae and one that's more aquatic than other salamandrids.

dane
16th February 2007, 21:24
I always think of squares are rectangles, but rectangles aren't squares kindof thing

TJ
17th February 2007, 11:13
Or like geckos are lizards but not all lizards are geckos http://www.caudata.org/forum/clipart/biggrin.gif

To elaborate on the above, not all "salamandrids" (salamanders of the family Salamandridae) are newts. The family also contains fire salamanders, for example. You can see a list at:

http://www.caudata.org/cc/species/species.shtml

It's said that unlike many other kinds of salamanders, newts don't have costal grooves, those vertical groves on the sides of the body. I can't think of any exceptions. It's also said that newts have rougher skin than other salamanders, but some highly aquatic newts like Cynops wolterstorffi actually have smooth skin...

(Message edited by TJ on February 17, 2007)

sherri
17th February 2007, 12:05
Thank you very much. Thats clear to me now http://www.caudata.org/forum/clipart/happy.gif

kenneth
17th February 2007, 13:52
What about the deposition of the eggs? With most species I can think of, the salamanders lay thier eggs in masses where as the newts lay thier eggs individually. ( as with the frogs..masses and the toads..singly or in chains )

benjamin
17th February 2007, 14:05
That's kind of true, but then there are the salamanders who gestate, also some newts will occasionally lay eggs in strings, and axolotls which are generally considered salamanders lay their eggs individually.

TJ
17th February 2007, 14:45
For an authoritative overview of Salamandridae, see this page at the Tree of Life web project:

http://www.tolweb.org/Salamandridae/15445

Among the distinguishing characteristics, these experts note that:

* all newts have aquatic larvae
* all newts utilize ponds or streams to reproduce
* newts are highly poisonous in all stages of their life history
* newts have rough-textured skin that is not slimy
* with newts, costal grooves usually are not distinct

But as they point out, the subdivision of Salamandridae into "true salamanders" and "newts" is an informal one.

This description makes me wonder though, which non-newt salamandrids are not poisonous in all stages of their life history, and which newts have distinct costal grooves?

kamil
17th February 2007, 14:59
Hi,

biologically there is no difference between a newt or a salamander (if not comparing the genders or species). The only difference is made in the language and that is not consequent too. The people call Urodela that mainly live in water or spend a longer time in water Newts and the ones living mostly terrestrial they call Salamander. But what are then the Andrias giant salamanders? In the german language there are even newts and salamanders within Ambystoma and other genders. So there is no real difference

michael
17th February 2007, 23:15
I think newt and salamander is more like turtoise and turtle. I don't think I would compare them to toad and frog. I think toad and frog is pretty arbitrary. A surinam toad is very closely related to an African clawed frog. Why in the world is the one a toad and the other a frog? The words toad and frog are often interchangeable.
I guess the only thing I'm certain of (maybe) is all newts are salamanders but not all salamanders are newts. A salamander that starts in water goes to land and then goes back to water I would call a newt. Some newts can spend most of their life in water e.g. Cynops cyanurus. I wouldn't call that newt like behavior. I guess that doesn't clear anything up.

cameron
18th February 2007, 00:19
Fire Salamanders give live birth by retaining the eggs in the cloaca until they hatch.

TJ
18th February 2007, 07:52
Perhaps a better example of an entirely or mostly aquatic newt would be something like Pachytriton brevipes or P. labiatus. I was surprised to find that Cynops cyanurus yunnanensis overwinter on land in the wild (or at least some juveniles do). Perhaps they're not as aquatic as keeping them in captivity would lead one to believe. Same goes for C. ensicauda, which spend much of their lives on land in the wild though they can be kept almost entirely aquatic in captivity.

I probably know less about anurans than most people here, but aren't "toads" more bulky, warty and generally found on land rather than in the trees or in the water (outside the breeding season, at least)? That seems to me distinctive enough to separate them in the mind, even though there's a grey zone in which there are some toad-like "frogs" as well as froggy toads. It all comes down to common perception and language use. When I see Bufo, I think "toad" not "frog" http://www.caudata.org/forum/clipart/biggrin.gif

I'm now starting to wonder whether Pachytriton have those distinct costal groves or not....