Curious, can millipedes change colors after a molt?

[BepopCola]

So, my story:
I have a communal setup. Last night I saw a gray millipede walking on the surface, but it quickly went back underground. I didn't get a picture .

It was of very similar length and width as the N. americanus I have in there. A little bigger if anything. The only problem it that I've only had the reddish colored N. americanus (see pic). There's an N. gordanus in the tank as well, it was a teeny tiny little guy last time I saw it (late November).

I also have a Philippine blue millipede in there, but it was much smaller the last time I saw it (early January). The shade of gray was similar the Philippine blue. I have another Philippine blue in a different tank, I got them at the same time, they were the same sizes, and that other one is still less than half the size of a N. americanus.

I have no idea how the big gray guy came to be.
Did someone just grow super quick?
Could someone have molted into a different shade?

Edit: I attached a photo of its head as it peeked out tonight.

 

[ErinM31]

So, my story:
I have a communal setup. Last night I saw a gray millipede walking on the surface, but it quickly went back underground. I didn't get a picture .

It was of very similar length and width as the N. americanus I have in there. A little bigger if anything. The only problem it that I've only had the reddish colored N. americanus (see pic). There's an N. gordanus in the tank as well, it was a teeny tiny little guy last time I saw it (late November).

I also have a Philippine blue millipede in there, but it was much smaller the last time I saw it (early January). The shade of gray was similar the Philippine blue. I have another Philippine blue in a different tank, I got them at the same time, they were the same sizes, and that other one is still less than half the size of a N. americanus.

I have no idea how the big gray guy came to be.
Did someone just grow super quick?
Could someone have molted into a different shade?

Edit: I attached a photo of its head as it peeked out tonight.

So, my story:
I have a communal setup. Last night I saw a gray millipede walking on the surface, but it quickly went back underground. I didn't get a picture .

It was of very similar length and width as the N. americanus I have in there. A little bigger if anything. The only problem it that I've only had the reddish colored N. americanus (see pic). There's an N. gordanus in the tank as well, it was a teeny tiny little guy last time I saw it (late November).

I also have a Philippine blue millipede in there, but it was much smaller the last time I saw it (early January). The shade of gray was similar the Philippine blue. I have another Philippine blue in a different tank, I got them at the same time, they were the same sizes, and that other one is still less than half the size of a N. americanus.

I have no idea how the big gray guy came to be.
Did someone just grow super quick?
Could someone have molted into a different shade?

Edit: I attached a photo of its head as it peeked out tonight.

Yes, millipedes can definitely change colors with molting and many species will gain or lose tinges of color as they grow or even change dramatically upon maturing.

The millipede you have circled in the first photo looks like N. americanus which I believe you said it is? The other two millipedes in that photo look like C. spinigerus.

The millipede in the second two photos looks like the gray morph of N. gordanus, although I cannot rule out the Philippine Blue as I am much less familiar but believe they are generally grayish until they mature. Do you recall whether the gray millipede is thicker than the N. americanus? If so, it is almost certainly N. gordanus.

What is more puzzling is, as you have pointed out, the sudden increase in size! Are you sure no other millipedes were in there? Of course, millipede growth rates can vary quite a bit depending on food availability, crowding and temperature. It would be helpful to have before and after pics or measurements...

Sorry I couldn’t be of any real help! Hopefully you’ll see them all above substrate at some point and can determine what’s what.

 

[BepopCola]

Yes, millipedes can definitely change colors with molting and many species will gain or lose tinges of color as they grow or even change dramatically upon maturing.

The millipede you have circled in the first photo looks like N. americanus which I believe you said it is? The other two millipedes in that photo look like C. spinigerus.

The millipede in the second two photos looks like the gray morph of N. gordanus, although I cannot rule out the Philippine Blue as I am much less familiar but believe they are generally grayish until they mature. Do you recall whether the gray millipede is thicker than the N. americanus? If so, it is almost certainly N. gordanus.

What is more puzzling is, as you have pointed out, the sudden increase in size! Are you sure no other millipedes were in there? Of course, millipede growth rates can vary quite a bit depending on food availability, crowding and temperature. It would be helpful to have before and after pics or measurements...

Sorry I couldn’t be of any real help! Hopefully you’ll see them all above substrate at some point and can determine what’s what.

The sudden increase in size is what's throwing me off as well. I am leaning towards N. gordanus, since it is very shy. Do they get thicker as they mature? I want to say its exactly the same size as the N. americanus.
I have no before pictures but it was about the size of a bumblebee milli when I introduced it into the tank. I was mistaken as well, it seems I had introduced two N. gordanus, an "Ocala Gold" and a "Smokey Oak."

 

[ErinM31]

The sudden increase in size is what's throwing me off as well. I am leaning towards N. gordanus, since it is very shy. Do they get thicker as they mature? I want to say its exactly the same size as the N. americanus.
I have no before pictures but it was about the size of a bumblebee milli when I introduced it into the tank. I was mistaken as well, it seems I had introduced two N. gordanus, an "Ocala Gold" and a "Smokey Oak."

Yes, Narceus gordanus are thicker than N. americanus. Were both N. gordanus millipedes that small as of last November? An unaccounted for millipede seems the most likely explanation, considering how long my N. gordanus would take to molt. I’ve had T’s grow that fast, but never a millipede! Of course there are quite a few species I don’t have experience with, including the Philippine Blue, but I didn’t think that they grew quite so fast either.

If you really did have a millipede grow up so fast, I hope you kept notes on all your husbandry!