Thanks for the query

Brown color marks sometimes means a clotted blood which is benign and will go away on its own. I am assuminng as i have to examined u. If it grows in size, becomes painful or u become febrile meet a doctor immediately

Have a healthy living

Hello, welcome to HCM. Nail plate pigmentation (melanonychia) is a rather common clinical occurrence. Melanonychia striata, or longitudinal melanonychia (LM), is characterized as either a dark brown or brown-black longitudinal band on a toenail or fingernail. The three most common variants of LM are melanocytic nevus, melanotic macule, and melanoma in situ. There have been reports of melanocytic nevus and melanotic macules progressing to melanomas. You must visit a dermatologist to get it evaluated. You may need a biopsy of it. Wish you good health.