Lilies: Lilies 101-Help with indenification of Lily Forms., 1 by Leftwood

Leftwood wrote:
He should make it easier and just use flower color, as a separate entry.

I won't ague with that if simplicity for easy of understanding is more important, but I do take the position that tepals (referencing sepals and petals together) is a needed term in the Lilium genus.

Sometimes sepals may be strongly recurved, while petals are only slightly recurved on the same flower (pic below). Also notice here that sepals are ruffled, while petals are not, and that in generally sepals are very different from petals in this flower. Such cases warrant the need for differentiation. Other circumstances better accommodate the use of "tepals", emphasizing the unnecessary need for differentiation, when referenced characteristics are uniform throughout. In this case, the use of "petals" or "sepals" would be inaccurate, and one would correctly use "petals and sepals" or "tepals". Either way, one is going to have to learn what sepals are, in relation to true petals. "Tepals", then, is an extension of the learned definition, and should come naturally.