Trochodendron
Trochodendron is a genus of flowering plants with one living species, Trochodendron aralioides, and six extinct species known from the fossil record. It was often considered the sole genus in the family Trochodendraceae, though botanists now also include the distinct genus Tetracentron in the family.
Species
- Trochodendron aralioides
- †Trochodendron beckii
- †Trochodendron drachukii
- †Trochodendron evenense
- †Trochodendron infernense
- †Trochodendron kamtschaticum
- †Trochodendron nastae
- †Trochodendron postnastae
- †Trochodendron protoaralioides
- †Trochodendron rosayi
Trochodendron aralioides is an evergreen tree or large shrub growing to 20 m tall. Trochodendron and Tetracentron lack vessel elements in their wood, a quite unusual feature in angiosperms. This has long been considered a very primitive character, resulting in the classification of these two genera in a basal position in the angiosperms; however, genetic research by the Angiosperm Phylogeny Group has shown it to be in a less basal position, suggesting the absence of vessel elements in these two genera is a secondarily evolved character, not a primitive one.