Trochodendron nastae
| Trochodendron nastae | |
|---|---|
| |
| Trochodendron nastae specimen | |
Scientific classification 
| |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Order: | Trochodendrales |
| Family: | Trochodendraceae |
| Genus: | Trochodendron |
| Species: | †T. nastae
|
| Binomial name | |
| †Trochodendron nastae Pigg,
Wehr , & Ickert-Bond, 2001 | |
Trochodendron nastae is an
extinct species of flowering plant in the family Trochodendraceae known from fossil leaves found in the early Eocene Ypresian stage Klondike Mountain Formation deposits of northern Washington state. T. nastae is one of the oldest members of the genus Trochodendron, which includes the living species T. aralioides, native to Japan, southern Korea and Taiwan[1] and the coeval extinct species T. drachukii from the McAbee Fossil Beds near Cache Creek, British Columbia.[2]
Taxonomy
Description of the new species by Dr. Kathleen B. Pigg,
Trochodendrales.[1]
T. nastae has been placed in the genus Trochodendron based on the overall shape of the leaves, the secondary vein structure, which forms weak chevrons bracing primary veins, and the tertiary veins forming four to five sided cells.pinnate as in T. aralioides.[1]
Trochodendron shares with Tetracentron the very unusual feature in
eudicots
), suggesting that the absence of vessel elements is a secondarily evolved character, not a primitive one.