Posts Tagged ‘tiger salamander’


These tiger salamanders retain gills into adulthood, and no, this is not an axolotl.

An axolotl is a species of tiger salamander that is always neotenic.

In this species, there are some that have neoteny and some do not.


Read Full Post »


(Warning: This song gets annoying fast!)

The animal singing this song is actually some species of tiger salamander from north of the Rio Grande. An axolotl is a species of tiger salamander from the lakes that once made up Mexico City. It is a neotenous species that reaches full maturity while still having gills, which salamanders generally only have when they are larvae. Northern species of tiger salamander can be neotenous, but generally, this is a trait of the axolotl.

Salamander species that retain their gills into adulthood are called perennibranchiate salamanders. The name means “always having branches,” which makes sense if you have ever seen an axolotl’s gills.

Now, it is possible to get an axolotl to metamorphose. However, I don’t know why anyone would want to do it.

It takes a certain amount of know-how in chemistry to get the iodine levels just right to make the axolotl metamorphose. It has to be high enough to get them to metamorphose and low enough to keep from killing the axolotl. And if the axolotl has reached sexual maturity with its gills, the chances are that it won’t live very long as a metamorphosed adult.

Here’s a really good page on the metamorphosed axolotl and includes comparisons between those animals and tiger salamanders. Many bait shops carry larval tiger salamanders, usually under the (incorrect) name of “water dog.”

(A water dog or mudpuppy is another perennibranchiate salamander. It is not the same thing as the neotenic tiger salamander or the axolotl. Please do not claim that you caught an axolotl in Ohio or New York.)

If I had an axolotl, I would keep him in the neotenic state, simply because that is the life it evolved to live. It is the life neotenic and the life aquatic.


Finally, I should note that wild axolotls are quite endangered. The introduction of tilapia and carp to the lakes in which they are native has been very bad for the species. The fish eat the axololts’ gills and their larvae.  It doesn’t help that these salamanders are found only in the lake system that is part of the largest city on the continent.

Read Full Post »


I had no idea that tiger salamanders were THAT big.

I live in the an area with a high diversity of salamander species.

However, one species that is notably absent from that list is the tiger salamander.  The nearest tiger salamanders are in Central and Western Ohio. The next nearest populations are in coastal Virginia and Maryland.

I have never seen a wild one.

But we still have this species of salamander that could eat a tiger salamander for breakfast:


Read Full Post »



The axolotl is a species of tiger salamander that is found the lakes around Mexico City. It is a neotenous species of tiger salamander, retraining its gills throughout its life. It can be stimulated into metamorphosis, if certain hormones are introduced into its system or if it gets iodine treatments. The British naturalist Julian Huxley was among the first to cause metamorphosis in the axolotl using hormones. However, the metamorphosed axolotl is an unhealthy creature that lives only a year or two afterward.  This lifespan is greatly shortened from the 10-15 years it would have experienced as a neotenous specimen.

They are found in these lakes, which are polluted, but pollution alone has not killed off the Axolotl. Carp and tilapia have been introduced. These fish have discovered tha Axolotl larvae are a good source of protein, and the axolotl cannot survive this level of predation.

Interestingly, even if this species went extinct in the wild, it would not be extinct in captivity. In fact, you can buy axolotls as pets, which are kept a diet of bloodworms, salmon pellets, and other food for carnivorous fish. It has been in capitivy for so long that different color morphs have been produced, including albino, yellow albino, and leucistic (like the one pictured at the top of the post).

The animal has some cultural significance for Mexican of Aztec ancestry, because the axolotl is the representation of the Aztec deity, Xolotl, the dog-headed deity of death. Xolotl feared he was about to be banished, so he turned himself into the salamander and hid in the lakes. (This story might explain why an unrelated but similar looking species of gilled salamander in the US is called a “water dog.”)

More information can be found here.

Read Full Post »

%d bloggers like this: