Three floral morphs were found in Valeriana scandens L.: perfect, pistillate 1, and pistillate 2. In perfect flowers, the corolla is longer than in the other morphs, with reflexed lobes at anthesis and a prominent gibbus at the tube base; anthers are longer and contain viable pollen grains; the pistil has a short included style/stigma and the smallest ovary, but a structurally normal embryo sac similar to that of the other morphs. In pistillate 1 flowers, the corolla is intermediate in size, and has radially displayed lobes at anthesis, and a softly prominent gibbus; anthers are small and devoid of pollen; the pistil shows a long exerted style/stigma. In pistillate 2 flowers, the corolla also has radially displayed lobes; anthers are similar in length to the perfect flower, but narrower, and contain nonviable pollen grains; the style/stigma is as short as in perfect flowers, and is exerted as in pistillate 1 flowers. The three morphs produce viable seeds, and have a nectary formed by single-celled trichomes located on the inner face of the gibbus. Pistillate 2 and perfect flowers have a septum that isolates the gibbus from the rest of the corolla tube, forming a nectariferous chamber. The gynomonoecious-gynodioecious sexual expression verified in V. scandens L. is a novelty for Valerianaceae.
floral nectary; gynomonoecy-gynodioecy; male sterility; stylar polymorphism
