Question: Aquatic newts developing enlarged lips

My colleague pointed out that, while he was observing his Triturus Carnifax,

the aquatic newts tended to have a thicker and more pronounced lips(nasolabia?).

I've tried searching for studies related to the difference - with no luck.

We came up with a few hypotheses such as :

1) To help it with feeding via assisting in holding onto prey as they suction-feed in water

2) Sexual/breeding related change, assisting in courtship

3) Secondary sensory organ

4) Secondary respiratory organ



Now, if anyone could illuminate us to the purpose and the significance of enlarged lips

of aquatic newts (we saw this in Triturus and Cynops Pyrrohgaster), it would be very

much appreciated.


And no, this is not about bloating/sick newts. There is nothing out of the ordinary except

a more pronounced lip feature in aquatic forms compared to the terrestrial form.


Any information/pointers in the right source would be very much appreciated.

Have any pictures? Seems really interesting. If it's just the males, it could be the mental gland, even though I think it's just for lungless salamanders....

Sith the turtle said:

Have any pictures? Seems really interesting. If it's just the males, it could be the mental gland, even though I think it's just for lungless salamanders....

Click to expand...

It's not really distinguishable with pictures - in fact, the photos in here :
Caudata Culture Species Entry - Crested Triturus species

also show the rounder and plumper lips.....

or am I seeing things now...?

I'm pretty sure its to help them catch things underwater. They get as close as they can to the food then suddenly snap their mouth open, this creates a vacuum that drags the pray rapidly into the newts mouth. The droopy upper lip means the vacuum effect lasts longer before the mouth is fully open and the pressure equalises.

There are some pictures in this thread about Ommatotriton.

http://www.caudata.org/forum/f1173-...proctus/83100-banded-newt-drooping-jowls.html

Yep, Chinadog nailed it. That is exactly what it is for

Chinadog said:

I'm pretty sure its to help them catch things underwater. They get as close as they can to the food then suddenly snap their mouth open, this creates a vacuum that drags the pray rapidly into the newts mouth. The droopy upper lip means the vacuum effect lasts longer before the mouth is fully open and the pressure equalises.

There are some pictures in this thread about Ommatotriton.

http://www.caudata.org/forum/f1173-...proctus/83100-banded-newt-drooping-jowls.html

Click to expand...

sde said:

Yep, Chinadog nailed it. That is exactly what it is for

Click to expand...

Thanks everyone, I knew I could count on the org! :grin:

Update : Seems this happens to most newts during their aquatic stage.



Does anyone know what literature that picture is from? I just found the screenshot online,
and the site does not site any source other than "an amphibian essay"...

I'm guessing it could be Marc Staniszewski's work but if anyone has information about the source please let me know - I'd like to read the whole thing

I have a copy of 'Amphibians in captivity' by Mark Staiszewski, its not from there. It looks like a pretty good book though, and it must be fairly recentish to have much detail on Neurergus species. I would guess its from 'Threatened newts and salamanders. Guidelines for conservation and breeding' Schulshnik/Gross, Its on my wanted list, but I don't have a copy yet.

Chinadog, your guess is right about the book! I've got it.

Chinadog said:

I have a copy of 'Amphibians in captivity' by Mark Staiszewski, its not from there. It looks like a pretty good book though, and it must be fairly recentish to have much detail on Neurergus species. I would guess its from 'Threatened newts and salamanders. Guidelines for conservation and breeding' Schulshnik/Gross, Its on my wanted list, but I don't have a copy yet.

Click to expand...

Thanks much, this goes on my list this fall