Didymelales

(botany) An order of dicotyledonous plants in the subclass Hamamelidae, characterized by the primitive nature of the wood, which has vessels with scalariform perforations, and a pistil, which has one carpel; dioecious, evergreen trees restricted to Madagascar.

An order of flowering plants, division Magnoliophyta (Angiospermae), in the subclass Hamamelidae of the class Magnoliopsida (dicotyledons). The order contains a single family with but one genus, Didymeles, with two species. These dioecious, evergreen trees are restricted to Madagascar. The wood has vessels with scalariform perforations, which is a putatively primitive feature. The leaves are alternate, simple, and entire. The flowers are small; the staminate ones are in open clusters, without perianth, with two stamens, and the pollen grains have three germinal furrows. The pistillate flowers are commonly paired in spikelike clusters; they are hypogynous and sometimes have 1–4 scalelike sepals but no petals. The pistil has but one carpet. This curious genus has often been included in the Hamamelidales; however, the primitive nature of the wood and of the pistil make it anomalous there. See also Hamamelidae; Magnoliopsida; Plant kingdom.