Will they remove my nail when they check my suspected subungual melanoma?

Most likely yes: Most likely yes. They would need to get a biopsy of the mole. If it is located underneath the nail- the nail has to be out so a biopsy can be done and enough tissue can be resected. Discuss with your dermatologist.

Usually yes: Usually removing the nail is the most effective way to get a good sample, and the best way to have your nail bed heal properly. The only exception might be if the area were on the edge of your big toe nail, perhaps the nail could be spared. Don't worry, the nail will grow back!

Usually: Most of the time, the nail will need to come off. If it can be avoided, i try to do so, but more often than not the nail has to go to get access to the area to get a biopsy.

Yes: But usually the nail will grow back.

Subungual melanoma: You will need the biopsy first to prove the diagnosis, then the surgery to remove the tumor. It could be removal of the part of the nail and the nail bed. It could be the whole nail too. It depends on how wide and deep is the tumor.