Trochodendron aralioides

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Trochodendron aralioides
Trochodendron aralioides 09072.JPG
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Order: Trochodendrales
Family: Trochodendraceae
Genus: Trochodendron
Species:
T. aralioides
Binomial name
Trochodendron aralioides

Trochodendron aralioides, sometimes colloquially called wheel tree, is a flowering plant and the sole living species in the genus Trochodendron , which also includes several extinct species. It was also often considered the sole species in the family Trochodendraceae, though botanists now include the distinct genus Tetracentron in the same family. T. aralioides is native to Japan, southern Korea and Taiwan. Growing in lower temperate montane mixed forests in Japan, and broad-leaved evergreen forest in the central mountain ranges and Northern parts of Taiwan. [1]

Contents

Description

It is an evergreen tree or large shrub growing to 20 m tall. The leaves are borne in tight spirals at the apex of the year's growth, each leaf leathery dark green, simple broad lanceolate, 6–14 cm long and 3–8 cm broad, with a crenate margin. The flowers are produced 10–20 together in a racemose cyme 5–13 cm diameter; each flower is 15–18 mm diameter, yellowish green, without petals, but with a conspicuous ring of 40–70 stamens surrounding the 4–11 carpels. The fruit is 2 cm diameter, woody, star-shaped, composed of 4–11 follicles, each follicle containing several seeds.

Genetics

Trochodendron aralioides shares with Tetracentron the very unusual feature in angiosperms, of lacking vessel elements in its wood. [2] 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 (early in the eudicots), suggesting the absence of vessel elements is a secondarily evolved character, not a primitive one. [3]

From sequencing the chromosome scale (19 chromosomes and 1.614 Gb in size) genome of the species it was seen that the divergence time between T. aralioides and its common ancestor with the core eudicots was ~124.2 Mya. [4]

Related Research Articles

<span class="mw-page-title-main">Buxales</span> Order of eudicot flowering plants

The Buxales are a small order of eudicot flowering plants, recognized by the APG IV system of 2016. The order includes the family Buxaceae; the families Didymelaceae and Haptanthaceae may also be recognized or may be included in the Buxaceae. Many members of the order are evergreen shrubs or trees, although some are herbaceous perennials. They have separate "male" (staminate) and "female" (carpellate) flowers, mostly on the same plant. Some species are of economic importance either for the wood they produce or as ornamental plants.

<i>Amborella</i> Species of shrub

Amborella is a monotypic genus of understory shrubs or small trees endemic to the main island, Grande Terre, of New Caledonia in the southwest Pacific Ocean. The genus is the only member of the family Amborellaceae and the order Amborellales and contains a single species, Amborella trichopoda. Amborella is of great interest to plant systematists because molecular phylogenetic analyses consistently place it as the sister group to all other flowering plants.

<i>Drosophyllum</i> Genus of carnivorous plants

Drosophyllum is a genus of carnivorous plants containing the single species Drosophyllum lusitanicum, commonly known as Portuguese sundew or dewy pine. In appearance, it is similar to the related genus Drosera, and to the much more distantly related Byblis.

<i>Aextoxicon</i> Species of plant

Aextoxicon punctatum, the sole species of genus Aextoxicon and family Aextoxicaceae, is a dioecious tree native to southern Chile and Argentina. Commonly known as the olivillo or aceitunillo, it is a large evergreen tree native to the forests of the Valdivian temperate rain forests and Magellanic subpolar forests of southern Chile's Pacific coast, where it forms is a canopy tree in the broadleaf forests. It can reach 15 m tall.

<i>Griselinia</i> Genus of flowering plants

Griselinia is a genus of seven species of shrubs and trees, with a highly disjunct distribution native to New Zealand and South America. It is a classic example of the Antarctic flora. It is the sole genus in the family Griseliniaceae. In the past it was often placed in Cornaceae but differs from that in many features.

<i>Gomortega</i> Species of plant

Gomortega keule is a tree native to Chile. It is the sole species of the genus Gomortega and, according to the APG IV system of 2016, of the monotypic family Gomortegaceae, assigned to the order Laurales in the clade magnoliids.

<span class="mw-page-title-main">Sabiaceae</span> Family of flowering plants

Sabiaceae is a family of flowering plants that were placed in the order Proteales according to the APG IV system. It comprises three genera, Meliosma, Ophiocaryon and Sabia, with 66 known species, native to tropical to warm temperate regions of southern Asia and the Americas. The family has also been called Meliosmaceae Endl., 1841, nom. rej.

<i>Trochodendron</i> Genus of flowing plants in the family Trochodendraceae

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.

<i>Tetracentron</i> Genus of flowering plants in the family Trochodendraceae

Tetracentron is a genus of flowering plant with a sole living species being Tetracentron sinense and several extinct species. It was formerly considered the sole genus in the family Tetracentraceae, though it is now included in the family Trochodendraceae together with the genus Trochodendron.

<span class="mw-page-title-main">Trochodendraceae</span> Family of flowering plants

Trochodendraceae is the only family of flowering plants in the order Trochodendrales. It comprises two extant genera, each with a single species along with up to five additional extinct genera and a number of extinct species. The living species are native to south east Asia. The two living species both have secondary xylem without vessel elements, which is quite rare in angiosperms. As the vessel-free wood suggests primitiveness, these two species have attracted much taxonomic attention.

The APG II system of plant classification is the second, now obsolete, version of a modern, mostly molecular-based, system of plant taxonomy that was published in April 2003 by the Angiosperm Phylogeny Group. It was a revision of the first APG system, published in 1998, and was superseded in 2009 by a further revision, the APG III system.

Asteropeia is a genus of flowering plants. The genus contains 8 known species of shrubs and small trees, all endemic to Madagascar. It is the sole genus in family Asteropeiaceae. Members of the family are evergreen trees or shrubs.

<i>Tetracentron sinense</i> Species of tree

Tetracentron sinense is a flowering plant native to Asia and the sole living species in the genus Tetracentron. It was formerly considered the sole species in the family Tetracentraceae, though Tetracentron is now included in the family Trochodendraceae together with the genus Trochodendron.

<i>Aphloia</i> Monotypic genus of flowering plants

Aphloia is a genus of flowering plants that contains a single species, Aphloia theiformis, the sole species of the monogeneric family Aphloiaceae. It is a species of evergreen shrubs or small trees occurring in East Africa, Madagascar, the Mascarene Islands and the Seychelles.

<i>Geissoloma</i> Monotypic genus of flowering plants native to the Cape Province of South Africa

Geissoloma is a genus of flowering plants in the monotypic family Geissolomataceae, native to the Cape Province of South Africa. The plants are xerophytic evergreen shrubs and are known to accumulate aluminum. It is sometimes called guyalone in English.

<i>Trochodendron nastae</i> Extinct species of flowering plant

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 and the coeval extinct species T. drachukii from the McAbee Fossil Beds near Cache Creek, British Columbia.

Trochodendron drachukii is an extinct species of flowering plants in the family Trochodendraceae known from a fossil fruiting structure found in the early Ypresian age Eocene fossils found in British Columbia, Canada. T. drachukii is one of the oldest members of the genus Trochodendron, which includes the living species T. aralioides, native to Japan, southern Korea and Taiwan and the coeval extinct species T. nastae from Washington state, United States.

<i>Pentacentron</i> Extinct genus of Trochodendralean plant

Pentacentron is an extinct genus of flowering plant in the family Trochodendraceae, consisting of the single species Pentacentron sternhartae. The genus is known from fossil fruits found in the early Eocene deposits of northern Washington state, United States. P. sternhartae are possibly the fruits belonging to the extinct trochodendraceous leaves Tetracentron hopkinsii.

<i>Tetracentron hopkinsii</i> Extinct species of flowering plant

Tetracentron hopkinsii is an extinct species of flowering plant in the family Trochodendraceae. The species is known from fossil leaves found in the early Eocene deposits of northern Washington state, United States and south Central British Columbia. The species was first described from fossil leaves found in the Allenby Formation. T. hopkinsii are possibly the leaves belonging to the extinct trochodendraceous fruits Pentacentron sternhartae.

Paraconcavistylon is an extinct genus of flowering plant in the family Trochodendraceae comprises a single species, Paraconcavistylon wehrii. The genus is known from fossil fruits and leaves found in the early Eocene deposits of northern Washington state, United States, and southern British Columbia, Canada. The species was initially described as a member of the related extinct genus Concavistylon as "Concavistylon" wehrii, but subsequently moved to the new genus Paraconcavistylon in 2020 after additional study.

References

  1. Lin, Cheng-Tao; Chiu, Ching-An (January 2019). "The relic Trochodendron aralioides Siebold & Zucc. (Trochodendraceae) in Taiwan: Ensemble distribution modeling and climate change Impacts". Forests. 10 (1): 7. doi: 10.3390/f10010007 .
  2. Li, Hong-Fang; Chaw, Shu-Miaw; Du, Chun-Mei; Ren, Yi (2011-06-01). "Vessel elements present in the secondary xylem of Trochodendron and Tetracentron (Trochodendraceae)". Flora - Morphology, Distribution, Functional Ecology of Plants. 206 (6): 595–600. doi:10.1016/j.flora.2010.11.018. ISSN   0367-2530.
  3. The Angiosperm Phylogeny Group (2009-10-01). "An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG III". Botanical Journal of the Linnean Society. 161 (2): 105–121. doi: 10.1111/j.1095-8339.2009.00996.x . ISSN   0024-4074.
  4. Strijk, Joeri S.; Hinsinger, Damien D.; Zhang, Fengping; Cao, Kunfang (2019-11-01). "Trochodendron aralioides, the first chromosome-level draft genome in Trochodendrales and a valuable resource for basal eudicot research". GigaScience. 8 (11): giz136. doi:10.1093/gigascience/giz136. PMC   6859433 . PMID   31738437.