equitant

adjective

(L. equitare: to ride) Of leaves, folded in half along the midline so that the adaxial surface disappears, and overlapping the edges of a similarly folded leaf on the opposite side of the stem, i.e. of leaves whose bases overlap the leaves within or above them, as in the Iris; referring to conduplicate and strongly sheathing leaf bases; e.g. Fissidens.