is one member or part of the calyx
of a flower
. It is the outer part of the perianth
, which comprises the sterile parts of a flower, consisting of inner and outer tepals
that are usually differentiated into petals
. The term tepal
is usually applied when the petals and sepals are not differentiated. However, in a "typical" flower the sepals
are green and lay under the more conspicuous petals.
The number of sepals in a flower is indicative of the plant's classification: dicots having typically four or five sepals and monocots having three, or some multiple of three, sepals.
There exists considerable variation in form of the sepals among the flowering plants. Often the sepals are much reduced, appearing somewhat awn-like, or as scales, teeth, or ridges. Examples of flowers with much reduced perianths are found among the grasses. In some flowers, the sepals are fused towards the base, forming a calyx tube. This floral tube can include the petals and the attachment point of the stamens.