Mudpuppies Vs Axolotls: Help?

I have a leucistic axolotl, but I want to be sure he is in fact, an axolotl. I would also really like to know the physical difference between mudpuppies, and axolotls. No matter what I research, I keep coming across pictures that seem almost identical to me! Can anyone tell me what a leucistic mudpuppy looks like? Or even, what a mudpuppy vs an axolotl in general looks like?
My axolotl looked like he was going to metamorphosize and even started to lose his gills the first week I got him. However, after a few days of continuing my water changes and constant feedings, he started to grow them back. I've heard stories of tiger salamander mudpuppies doing this, but not axolotls! Can anyone help? (I have pictures of when I got him, when he started losing his gills, and how they have begun growing back so far)







(Also, his red face and legs tend to happen when he gets excited for food, as his tail and gills turn red as well. When he's asleep or finally just calmed down, they turn back to his normal white color. He also stands up on his hind legs when he wants food, so that's pretty funny!)
EDIT: why is his first photo upside down????

I'm 99% sure that's an axolotl.

Mudpuppies (Necturus maculosus) are longer in the body, not as long as say sirens, but longer than axolotls and larval tiger salamanders. The head shape on mudpuppies is also slimmer, more like an arrow head for lack of a better comparison. Mudpuppies also don't appear to have very prominent caudal (tail) fins, vs an axolotl which can have very high caudal fins and the majority of the tail is fin, like in your first picture. If you're on google adding "leucistic" to your search for either mudpuppy or larval tiger salamander just brings up images of leucistic axolotls. There was only one or two photos in the larval tiger salamander search I thought maybe could be actual leucistic tigers. Much easier to compare the three with google searches of the actual animal without added adjectives.

Larval tiger salamanders to me, look very close to axolotls physically, most likely because they're closely related. I'm not confident I could split them apart without more experience in both species. To me it looks like tigers have a more pointed face. But they have the same digit counts and anatomy. Coloration would be an easy spot, but some wild type axolotls can throw colors that look very similar to tigers too, depending on the chromatophore levels. But since yours is leucistic that doesn't matter.

The gill issues look to be from poor water conditions. Was your tank cycled before you put the animal in? Do you have a test kit to continue to monitor the water? If the filaments started to grow back after repeated water changes than that also leads me to believe it was due to bad water quality. There are a few threads here that document what a morphing axolotl and a morphing tiger look like. When in doubt you could always compare your animals. But axolotls don't tend to morph often, typically they just die.
There are other tells of a morph in progress, eyes, appearance of a tongue and "teeth".


If someone more versed in mudpuppies, tigers and their differences wants to chime in or correct me if I got something wrong that would be lovely. I've only had an adult tiger and my axolotls. If there's more to learn I wouldn't be opposed to learning. A final side note is that larval tigers are often called "waterdogs" which doesn't help make things less confusing waterdogs aren't mudpuppies.

From any thing I've seen, Axolotls seem to have the bluntest features of the three....mudpuppies have pointier faces and are more slender, for example, as well as some species being a bit longer on average. Tiger salamanders look a lot closer, but don't seem to have quite so rounded a snout, think something along the lines of a shovel compared to a spoon. In shape, not size.