Pseudantic theory

In Botany, the pseudantic theory of the origin of the angiosperms postulates that this group of plants has originated from representatives of the gyneophytes of gymnosperms, which present unisexual flowers. The hermaphrodite flower of the angiosperms would have originated by reduction of an inflorescence that has the appearance of being a single flower (a pseudanto, a structure similar to the inflorescences that presents / displays the family Euphorbiaceae denominated ciatio) that carried both feminine and masculine flowers ). By successive reductions the masculine flowers would have originated the androceo and the feminine the gineceo of the hermaphrodite flowers of the angiosperms, so that each one of the cycles of an angiosperm flower would have originated of the different flowers of a pseudanto, of there the name of theory. The perianth is these hermaphrodite flowers would come from the bracts of the original unisexual flowers. This theory is based on the external similarities of the leaves of Gnetum and the similarity of the polyester sacs of Ephedra with the angiosperms. However, there are characteristics of gnetophytes that are very different from those of angiosperms, such as the histological origin of phloem cells, cell types of xylem and differences in relation to gametophytes.

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