A pair of firefly axolotls, which have had their tails swapped. Image credit: Oliver Perry.
Introduction
Over the past few years, the Ambystoma mexicanum, colloquially known as the axolotl, has garnered a sharp increase in both general interest and ownership, having become one of the most widely kept species of amphibian in the pet trade.
As is the case with many other animal species, axolotls have been bred for sought-after traits, such as an array of different colors, or morphology. This is due to two primary reasons— one being for research purposes, and the other, to appeal to potential buyers.
Although most axolotl morphs have been “created” through selective breeding processes, some of them are produced through artificial means, which is the case with what has come to be known as “firefly” axolotls.
So, what exactly are “fireflies?”
A firefly axolotl is an artificially-made morph in which typically the tails of two individuals are swapped. Fireflies were first created by Lloyd Strohl II (Strohl’s Herptiles) as part of his research on the distribution of melanocytes in axolotls, particularly in mosaic axolotls.
These axolotls were produced through skin grafting during the embryonic stage of the axolotl’s development, where it is not yet able to register pain. At the conclusion of the study, the produced fireflies were sold as pets, and Strohl has not made any new individuals since then.
Similar to firefly axolotls, “candy corn" axolotls have had more than one section of their tail grafted. This pair has also had sections of their foreheads swapped. (source)
However…
Although Strohl had ceased production of fireflies following the conclusion of his research, the popularity and demand for these types of axolotls has nonetheless persisted, creating a niche in the market for others who were able to figure out how to create them.
Unlike Strohl’s method of creating fireflies through embryonic grafting before they are hatched and while they are still unable to sense pain, the firefly axolotls being produced today are made through skin grafting performed on young axolotls who have already hatched from their eggs. These axolotls are anesthetized in order to perform the surgery, and are not given any form of pain relief following the procedure.
Image showing an axolotl that underwent a post-embryonic eye-swap surgery, a procedure with a known high rate of failure. (image from BeautifulLotls)
In addition to this, these individuals undergo these surgeries for purely cosmetic purposes, as opposed to research as they were originally intended for. These axolotls with different patterns of skin grafting are becoming popular on the market, and buyers are willing to pay a pretty penny for them!
New Surgeries and Alterations
These newer types of artificially created axolotl morphs often involve skin grafts of more invasive areas apart from solely the tail. This can include parts of the abdomen, face, and the eyes. These new techniques have led to other surgically-imposed defects, such as disfigurement of the caudal fin and eyelessness.
Images showing deformed tail of “dinosaur" axolotl created by skin grafting on the tail. (source)
Axolotls are now being mutilated to create more intricate patterns on their tails, such as checkerboard pattern, candy corn, or dinosaur axolotls. Skin grafting is not always a successful procedure, and there have also been times when only one specific firefly axolotl is desired, resulting in the second axolotl being discarded after taking its tail.
Conclusion
While axolotls will always be a pet that is bred for aesthetically pleasing features, it is important to understand which alterations are painful or make an axolotl susceptible to a lower quality of life. Since firefly axolotls and other modified morphs are now produced using axolotls that are no longer in the embryonic stage, many in the community of axolotl husbandry have agreed that this is unethical and that they should not continue to be produced in the future. However, as long as there is a demand for these unique-looking axolotl morphs, then breeders will continue to find a way to create them for profit.