Cardinal Tetra with a "goatee"?

[RightTurnClyde]

Not sure if this is the right place to post this, since the fish is not necessarily unhealthy, but I noticed on a couple of my new Cardinal Tetras, they have what appears to be a very small flap of skin that hangs down under their bottom lip. On the bigger one, it is much easier to see. It's right in the middle and is triangular in shape, like a little beard or a goatee. Just wondering if anyone else has ever seen this? Is it maybe a gender specific trait? Or is it possibly just injured and that is a scale hanging loose?

Otherwise, they are all behaving just fine, swimming around the middle, looking pretty. No visible signs of ich or anything.

 

[Delapool]

I've never seen this. What colour is it? Were they always like this or has it become larger? Nothing springs to mind though.

 

[RightTurnClyde]

I've never seen this. What colour is it? Were they always like this or has it become larger? Nothing springs to mind though.

I've only had them since Tuesday 4/22, so it's always been there. No change that I can see. I'm not too worried about it. They are still so small, it's hard to get a good look at it, but last night, it looked more like just a very very small bulbous growth on the bottom lip. I only really notice it on one the little guys, and that's if I really look hard. It's the same color as it's mouth.

They are still behaving fine, in fact, they are getting braver each day. They are actually starting to come to the top when I get close to the tank, thinking they are going to be fed.

 

[Delapool]

Ok, sounds great. Just keep an eye on in case it gets bigger. Hopefully missing scale or something