Citrus Leaf Miner damage. Use the search for this forum and look it up, also is abbreviated as CLM. Mostly cosmetic unless your tree is very young, then may stunt growth.

Some additional info is that you didn't need to remove the leaves as the tiny pest has done its damage and gone off to mate and lay eggs on some other citrus.

The leaves were still mostly working to make food for the plant. If your plant has many leaves affected, it may do better just leaving the damaged leaves. I have one recovering Tangor that only had few dozen new leaves and the CLM got them ALL.

Thank you Greg" it was only a few leaves much to my relief. I will need to check my other trees that are in pots near by. Sorry to hear about your tree. Hope it recovers soon. Maggy