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Weird Animals - the Wooper Rooper - Axolotl

Would You Like to Be Like Me - Always Looking Young?

I have neoteny. It breaks up the monoteny.

I have neoteny. It breaks up the monoteny.

The axolotl (pronounced AHK-so-LA-tuhl) is a rare Mexican salamander that forever looks like a teenager. Not a human teenager – though I have seen a few human teen specimens who look peculiarly like axolotls. I’m referring to the fact that throughout its adult life, the axolotl has the rare capability of retaining its larval features. It looks forever young.

What is neoteny?

Larvae of the axolotl fail to undergo metamorphosis, so the adults remain aquatic and gilled. This condition, called neoteny, means it keeps its tadpole-like dorsal fin, which runs almost the length of its body, and its feathery external gills, which protrude from the back of its wide head.

Axolotls (Ambystoma mexicanum) live exclusively in the lakes, channels and wetlands that comprise the Xochimilco Lake complex underlying Mexico City. They are the best-known of the Mexican neotenic mole salamanders related to the Tiger Salamander family.

But they differ from most other salamanders because they live permanently in water. In extremely rare cases, an axolotl may progress to maturity and emerge from the water, but the majority are content to remain underwater as outsized larvae. Males and females mate underwater and the females lay eggs on nearby structures such as plants.

Walking Fish, Water Dog or Wooper Rooper

Often referred to as “walking fish,” axolotls are salamanders, not fish, and confine their walking to the bottom of the lake or aquarium. The name, axolotl, is derived from the Aztec term, nahuatl, which means “water dog.” They are often purchased as pets in the U.S., Great Britain, Australia and Japan. The Japanese refer to them as “wooper rooper” (u-pa-ru-pa).

They measure up to 12 inches in length and may weigh 2 3/4 to 8 ounces. In their natural habitat, they are usually black or chocolate-brown and sometimes cream-colored. In captivity they are gray, shades of brown, white with black eyes, golden albino, pink, even multi-colored. That variety is known as he “harlequin Mexican walking fish.”

Beautiful Axolotl

Can you tell that I'm 12 years old?

Can you tell that I'm 12 years old?

Axolotl – the Frankenstein of the brine

People and most animals are able to sufficiently heal a cut, replace portions of dead or damaged skin, or even regenerate a small portion of an internal organ. But axolotls have the unique ability to completely regenerate not just their limbs and tail, but even heart and brain cells! Listen up, Dr. Frankenstein. Instead of merely forming scar tissue over a wound, the axolotl can regenerate entire body parts, including gills, eyes, kidneys, even large portions of its liver.

If it loses its tail, it can eventually replace it – skin, muscle and all. Even portions of its spine and brain can be regenerated, something which is near-impossibility with almost every other vertebrate. Juvenile axolotls seem to be able to regenerate body parts quickly, while adults either replace parts more slowly or not at all.

Axolotls are used extensively in scientific research due to their ability to regenerate most body parts, ease of breeding, and large embryos. These unique qualities have caused them to be one of the most scientifically studied animals in the world.

Axolotls are fairly long-lived, surviving 10 to 15 years on a diet of mollusks, worms, insect larva, crustaceans, and some tiny fish. Accustomed to being a top predator in its habitat, this species has begun to suffer from the introduction of large fish into its lake habitat. Large numbers of these fish, both carp and tilapia, compete ecologically with axolotls for food, and also eat axolotl eggs. Natural threats include predatory birds such as herons.

Axolotls are becoming "ax-o-littles"

Populations of axolotls are in decline and disappearing as the demands of nearby Mexico City (over 18 million people) have led to the draining and contamination of much of the waters of Xochimilco Lake. They are also popular as pets for tropical-fish-lovers, and roasted axolotl is considered a delicacy in Mexico. Scientists continue to use them in research studies, further shrinking their numbers.

For these reasons axolotls are listed as endangered and on the verge of becoming extinct on the annual Red List of threatened species. Recent surveys suggest that only 700 to 1,200 axolotls survive in six scattered areas within the Xochimilco area of the Mexican Central Valley.

© Copyright BJ Rakow Ph.D. 2010, 2011. All rights reserved. Author, "Much of What You Know about Job Search Just Ain't So," 

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Comments for the Wooper Rooper - Axolotl

drbj and sherry (author) from south Florida on April 20, 2015:

Thanks for the visit and the kind words, Biomedical. If axolotls no longer live in the wild that is our great loss.

Robert A. Avila, PE, MCE from Kiev, Ukraine on April 20, 2015:

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This is very well written. Voted up!

I included the axolotl in my list of 16 Living Things that can regenerate. Check it out here:

PS- It is now official, axolotls no longer live in the wild. A search by scientists turned up none. :(

drbj and sherry (author) from south Florida on April 16, 2014:

Hi, stricktlydating, yes, they are endangered. Although they may be common as unique pets in Australia, in Mexico they are often caught and eaten as a delicacy. Take good care of your unusual fish. And thanks for stopping by.

StrictlyQuotes from Australia on April 15, 2014:

Wow I never knew they were endangered, they are so common in Australia in almost every pet shop, here in Australia. They sell alongside goldfish. I have enjoyed them as pets for years.

drbj and sherry (author) from south Florida on April 08, 2013:

You just stated one of the maxims that guides my life, Patricia, so we are now sisters - like it or not. I, too, find that the more I learn the more I need to keep learning. Yes, the axolotl is unique and it was my pleasure to share these wooper-rooperish details. Thanks for the angels, m'dear.

Patricia Scott from North Central Florida on April 07, 2013:

Well, I am simply amazed. What I do not know will fill the Grand Canyon. It seems the more I learn the more I have to learn.

Neither the axolotil or wooper rooper have ever crossed my path. Nor have I read of them. They are unique indeed.

Thanks for sharing this with .

Sending many Angels to you and yours this evening. :) ps

drbj and sherry (author) from south Florida on February 21, 2013:

Not surprised they are new to you, Chris, they hang out mostly south of the Border in Mexico. Thanks for finding them and your laudatory comments.

carolina muscle from Charlotte, North Carolina on February 21, 2013:

I always learn something from your posts-- I never even heard of these little critters. nicely done.

drbj and sherry (author) from south Florida on November 27, 2012:

Nice to meet you, zaton. Delighted your found this hub in Google. Strictly speaking, although the axolotl is called a walking fish, it is actually a salamander that lives only in the water. And it does its walking on the bottom of a lake or in an aquarium.

Zaton-Taran from California on November 27, 2012:

Excellent and very informative hub - I did a Google search on fish lizard and found your site on like the 2nd or 3rd page. Happy I did - this is great evidence for evolution (when people say things like: "how come there are no fish with legs?") etc.

drbj and sherry (author) from south Florida on May 10, 2012:

Thanks for the visit, Mia. Wooper rooper is the name the Japanese use when referring to the axolotl. But I don't think this colorful salamander would mind if you called it a wooper looper.

Mia on May 10, 2012:

Wooper looper, not wooper rooper.

drbj and sherry (author) from south Florida on September 06, 2011:

Axolotls are not easily found even in the U.S. I would suggest you check out pet and pet supply stores in Turkey if such stores exist. on September 05, 2011:

how can i buy it? ?'m from turkey and ? want to buy an axolotls please communicate with me

drbj and sherry (author) from south Florida on March 26, 2011:

Nice to meet you, Melissa. Thank you for including that site which will assist axolotl lovers to learn whether their beloved pets are male or female. But not in California. Your diligent research is much appreciated.

Melissa on March 26, 2011:

Hi, just found this article. Great information however in California axolotls are illegal. Also to the person wondering about sexing, check out this page here. It is actually pretty easy to tell the difference once they hit around 5-6 months of age.

More information on California laws here (to be more specific Title 14, Excerpts §671 is what you want to look at.)

drbj and sherry (author) from south Florida on January 16, 2011:

To muffinator 23 who asked about purchasing an axolotl: Check out the pet stores in California that sell tropical fish. They can direct you to the dealer who stocks axolotls. Thanks for your interest. This unique amphibian is very special.

andy on January 07, 2011:

thank you

drbj and sherry (author) from south Florida on January 06, 2011:

Hi, andy. I have learned there are only two reliable methods of distinguishing male axolotls from females.

The first is that mature females tend to have very rounded bodies because of the number of eggs present in their bodies. And the sexually mature male's cloacal region (within its belly between its lower legs) is swollen, while that of the sexually mature female is considerably less so.

It's difficult even for experts to tell the difference though, so perhaps you can purchase another axolotl and watch to see if there is an attraction (?).

andy on January 06, 2011:

is there an easy way to tell which one in male and female? as i already have one and want to get one more.

drbj and sherry (author) from south Florida on December 11, 2010:

You win the award, cvxgh, for short, difficult-to-ascertain-the-hidden-meaning-of comments. :)

cvxgh on December 10, 2010:


drbj and sherry (author) from south Florida on August 10, 2010:

You are so right, jason. Not only should we save the axolotls, but study them to learn their regeneration secrets. Thank you for stopping by and commenting. Appreciate it.

jasonycc from South East Asia on August 10, 2010:

Incredible animal. They can regenerate their heart and brain cells.. wow they are way ahead of the human species. Save them.. save them.

drbj and sherry (author) from south Florida on July 19, 2010:

Hi, kal, I didn't know axolotls were illegal in NJ - buy one from a fish place in NY. Just kidding.

They are cute looking. If you ever get to Xochimilco Lake near Mexico City, you may find one in the fish flesh. Thanks for the visit.

kaltopsyd from Trinidad originally, but now in the USA on July 18, 2010:

Another cool animal, drbj!!! They're kind of cute (like the platypus, hehe). I want one! I want one! Where can I buy one of these little critters? Forget it. Don't answer that. :) Thanks for another awesome Hub. I'm so excited right now. I'm going to go look them up. Think my puppy will like a pet axolotl? :D Too bad they're illegal in NJ (I'm mad).

P.S. it looks like a pokémon. HAha

drbj and sherry (author) from south Florida on July 12, 2010:

I agree wholeheartedly with you, Aaron. Axolotls are delightful pets and too special to have them disappear from our planet.

Thank you for visiting. Have you had your black and yellow pets for long?

Aaron on July 06, 2010:


I have two axolotl's one black and one yellow, both female.

they are gourgous creatures. I think a lot more effort needs to be put into increasing there numbers, because it would just be such a shame to see them extinct.

drbj and sherry (author) from south Florida on June 02, 2010:

Hi, ian, thanks for stopping by. Was that "wow, OMG," an expression of delight or disgust?

I think they are more like cute. Many folks keep them in fish tanks as pets.

ian on June 02, 2010:

wow omg

drbj and sherry (author) from south Florida on January 06, 2010:

Rob, I agree - this little creature is too special to disappear from the planet. Funny you should mention olms. I was going to write about them first but then discovered axolotls which I thought more interesting.

rob on January 06, 2010:

save the axolotls! olms 4 life!

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