Discovering a tongue wart can be a stressful experience which is caused by a human papilloma virus that is sexually transmitted from one person to another. A single tongue wart can appear, but often they come in small clusters. The virus is highly contagious and spreads easily and rapidly, and thus often form small clusters on an area of the tongue. The warts are also very fast-growing and they have a scaly texture to them. In general, if you have a tongue wart you will know it as it will be quite obvious and hard to miss.