Tepals are elements of the perianth, or outer part of a flower, which include the petals or sepals. The term tepal is usually used when all segments of the perianth are of similar shape and color, or undifferentiated. When different types of organs can be distinguished, they are referred to as petals and sepals. Undifferentiated tepals are thought to be the ancestral condition in flowering plants. Amborella, which is thought to have separated earliest in the evolution of flowering plants, has f… (More on Tepal)