White bump on plastron

[Graceylou34]

Me and my mom went to clean off my tortoise and we noticed when we turned him over there was a big slimey white bump on his plastron. There still some dirt on it b/c we didn’t want to hurt him. I’m having trouble identifying what it is. Does anyone know what it could be?

 

[Yvonne G]

It's just dirt. Wipe it off, it won't hurt hi.