Difference between aquatic and terrestrial

[Niels D]

He's not as impressive as Niels'.

View attachment 19586

Of course he is as impressive! Look at his nice pattern.

 

[caleb]

There are three different sources of coloration in amphibians.

I think you missed melanin.

So...a red eft living in the wild then must get his carotenoids from some type of terrestrial diet - does anyone know which? Ants? Centipedes? Beetles?

There was a study on Cynops pyrrhogaster in Japan that aimed to identify from where terrestrial juveniles got their carotenoids:
Matsui K., Mochida, K. & Nakamura, M., 2003. Food Habit of the Juvenile of the Japanese Newt Cynops pyrrhogaster. Zoological Science 20:855-859.

They found the most significant groups of prey by weight to be fly larvae, amphipods, beetle larvae, and springtails (in that order, for well-grown red bellied juveniles). They didn't come to any conclusion as to which of these are most likely to be the source of their carotenoids.

Aquatic amphipods (e.g. Gammarus) can certainly have high concentrations of carotenoids, maybe terrestrial ones can too? That doesn't really help for red efts, though, as I don't think there are any terrestrial amphipods in the US.


Does anyone know if there's much variation in the intensity of red efts in the wild? There's certainly a lot of variation in the carotenoid related belly colours of wild Lissotriton in the UK.

 

[Azhael]

I can definitely share and agree that i´ve seen large variation in L.boscai and L.helveticus. But i have nothing to contribute about members of other genera. These variations in Lissotriton occur within the same breeding populations and can be very stricking.
Haven´t pterins been shown to accumulate from the diet too in some if not all caudates? I think it was riboflavins that i saw mentioned.

I always assumed that isopods were the key for terrestrial species, but it was just a guess by association to other crustaceans. This is a topic that i find fascinating so thank you both for chiming in! Any other info on the subject would be most apreciated.

 

[Ed]

Please excuse any mispellings as I'm trying to shake a headache.

I think you missed melanin.

Ah, sorry it is lumped in my head as being part of the chromatophores...

There was a study on Cynops pyrrhogaster in Japan that aimed to identify from where terrestrial juveniles got their carotenoids:
Matsui K., Mochida, K. & Nakamura, M., 2003. Food Habit of the Juvenile of the Japanese Newt Cynops pyrrhogaster. Zoological Science 20:855-859.

They found the most significant groups of prey by weight to be fly larvae, amphipods, beetle larvae, and springtails (in that order, for well-grown red bellied juveniles). They didn't come to any conclusion as to which of these are most likely to be the source of their carotenoids.

The problem with the article is that it didn't establish any baselines for carotenoid contents, the implication is that the most commonly ingested prey species would be the highest in carotenoids but this may not be the case. Storage and sequestering of the carotenoids can be independent of frequency in the diet.

Aquatic amphipods (e.g. Gammarus) can certainly have high concentrations of carotenoids, maybe terrestrial ones can too? That doesn't really help for red efts, though, as I don't think there are any terrestrial amphipods in the US.

I think the terrestrial ones have colonized beach areas in North America but aren't found in the regions where the newts are found.

Does anyone know if there's much variation in the intensity of red efts in the wild? There's certainly a lot of variation in the carotenoid related belly colours of wild Lissotriton in the UK.

I haven't located anything that documents it as of yet so we are going to have for the moment rely on anecdotal reports. I've seen some differences with some populations being a very vivid red and others a more yellowish orange.

If I remember correctly, yellow pteridines have been found in adult Notopthalmus. This paper indicates carotenoids in the red spots of the adults but not pteridines (http://akdavis.myweb.uga.edu/DavisPublications/pdfs/Davis%20and%20Grayson%202008.pdf) but I'm not convinced that there may not be an error in reference.

Some comments,

Ed

 

[Ed]

I can definitely share and agree that i´ve seen large variation in L.boscai and L.helveticus. But i have nothing to contribute about members of other genera. These variations in Lissotriton occur within the same breeding populations and can be very stricking.
Haven´t pterins been shown to accumulate from the diet too in some if not all caudates? I think it was riboflavins that i saw mentioned.

I always assumed that isopods were the key for terrestrial species, but it was just a guess by association to other crustaceans. This is a topic that i find fascinating so thank you both for chiming in! Any other info on the subject would be most apreciated.

If I remember correctly, riboflavin can be converted to pterins but in multiple vertebrate taxa, the uptake of riboflavin is fixed so dietary sources are minimized.

Ed

 

[Ed]

I should also add that carotenods are important to caudates for various metabolic requirements but that there are significant differences in how they are used. For example, in anurans, beta carotene appears to be poorly converted to vitamin A, which contributes to decreased immune function, poor fertility and poor development of embryos. There is also data that indicates this may also be the case in caudates see for example,

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1198201/pdf/biochemj00895-0128.pdf

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1198202/pdf/biochemj00895-0131.pdf

 

[EasternNewtLove]

Can you explain how you went about making them be aquatic as efts? Correct me if I'm reading this wrong.

 

[Niels D]

Not a problem. Just raise your larvae in the water as normal. When they start to loose their gills give them a little piece of land (turtledock or something like that). They will get on land after a while. Keep feeding them in the water though and they will return to the water after a couple of days. I don't know if this method works for other species.

 

[EasternNewtLove]

Thanks! I'll test it out when my eggs hatch in the next few weeks/months.

 

[Red Eft14]

My red eft is 2 inches and it has been that size since I got it...how do you know when they are suppose to turn aquatic,when they turn brownish,greyish,greenish?

 

[Niels D]

Thanks! I'll test it out when my eggs hatch in the next few weeks/months.

Congradulations with the eggs. I've seen a lot of amlexus with my notos lately, but they won't lay any eggs. There's no amplexus anymore, so I really hope that I will heave better luck next spring.

I've also lost a female yesterday. It was my very first noto! *sob* Don't know what caused her death, but I wouldn't be surprized if it was old age.

 

[Niels D]

Here's an update. The two terrestrial notos are still smaller than the aquatic one. I've noticed that one of the terrestrials hasn't got any spots, though all our adults do have them. The spots aren't red, except the spots of the aquatic noto.

Terrestrial notos 4cm:

Aquatic noto (5cm) in comparison to the biggest terrestrial.

 

[obicat]

Looking good! And its made me realise how much mine have changed colour! I reckon by spring time they'll be aquatic as they are now a murky green beige colour.

 

[EasternNewtLove]

So would I be able to do this with a WC Noto eft? I'm really afraid of an accidental drowning.

 

[Niels D]

I really don't know the answer to that question, but I think it's possible. Raising the efts aquatic is using the adaptation capacity of the animal for your own use. Still, are you willing to take the risk?

 

[EasternNewtLove]

No. Im not willing to take the risk. Do you know if this method makes them pass through the eft stage faster? Or does it just accelerate growth?

 

[froggy]

Interesting. In this species, it seems that skipping the terrestrial phase only occurs in some populations. It´s likely that there is at least some genetic component controlling this, so, if the efts want to go terrestrial (particularly if they go red), you probably won´t have much luck keeping them in the water. Field research shows that they grow faster in the wild, too, probably because they have more extended periods suitable for feeding (terrestrials can´t go out during very hot, dry or cold weather). The attached paper deals with this (in a very long-winded way!)

C

 

[Niels D]

I don't know if it shortens the eft stage, because allready have all the features of an adult. Here we have a couple of keepers that use this trick, but not only with N.v.viridescens and louisianensis. We've also got a lot of bloodlines and untill now it has worked for all of the offspring.

It looks a bit like raising H.orientalis or T.verrucosus aquatic by putting a lot of Java moss in your tank. I'm not a scientist though, so I'm glad that this method works with my animals. No matter what subspecies, all efts loose their red colour though and that's a downside.

 

[Niels D]

Darnit. Our stud Noto male has got fungus on it's tail just when he was buisy with our ladies. He's still acting like a healthy newt, but I'm worried nonetheless. Put him in the fridge in a tiny tank with some eSHa2000 and a little bit of salt in the water. The other males aren't interested in our to females, so I hope our fungus Noto did his job before he got seperated. What do you think:

 

[Azhael]

Sorry to hear the male developed fungus. This is waaaay too common.
I bet my left foot pinkie that female is full of eggs, fingers crossed she had time to pick up a spermatophore!