Ristantia pachysperma
| Yellow penda | |
|---|---|
| |
| Tree at Cape Tribulation | |
Scientific classification 
| |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Angiosperms |
| Clade: | Eudicots |
| Clade: | Rosids |
| Order: | Myrtales |
| Family: | Myrtaceae |
| Genus: | Ristantia |
| Species: | R. pachysperma
|
| Binomial name | |
| Ristantia pachysperma | |
| Synonyms[3] | |
| |
Ristantia pachysperma, commonly known as yellow penda, is a species of plants in the clove and eucalyptus family Myrtaceae. It is native to the Wet Tropics bioregion of Queensland, Australia, and is listed as critically endangered. It was first described in 1982.
Description
[edit]It is a large rainforest tree reaching up to 35 m (115 ft) in height, with brown furrowed bark and (sometimes) buttresses. The leaves are simple, arranged alternately or in whorls on the twigs, and are obovate in shape. They can grow up to 21 cm (8.3 in) long and are attached to the twig by a petiole (leaf stem) up to 12 mm (0.5 in) long.[4][5][6][7]
The inflorescences are produced from the leaf axils and are about 10 cm (3.9 in) long. They carry numerous quite small flowers, each with five white petals about 3 mm (0.12 in) long. Stamens number about 100 and are arranged in groups opposite the petals, each group with up to four sterile stamens and 15–20 fertile ones.[4][5][6][7]
The woody fruit is about 18 mm (0.7 in) diameter, with three locules or segments, and they usually contain one or two seeds per fruit.[4][5][6][7]
Taxonomy
[edit]This species was first described in 1886 as Xanthostemon pachyspermus by botanists Ferdinand von Mueller and Frederick Manson Bailey. It was described again in 1920 by Cyril Tenison White and William Douglas Francis, who, unaware that they were dealing with the same plant as Mueller and Bailey's earlier work, gave it the combination Tristania odorata. In 1951, having realised the error, Francis published a new combination, keeping the earlier species epithet pachyspermus but placing it in the genus Tristania.[8] By 1980, botanist Peter Gordon Wilson had recognised that Tristania contained a number of species that were not closely related,[9]: 10 and he published a full revision of the genus in 1982, resulting in the creation of the new genus Ristantia and the transfer of this species to it.[7]
Etymology
[edit]The name Ristantia is an anagram of Tristania.[7]: 443 The species epithet is derived from the Ancient Greek words păkhŭ́s, thick, and spérma, seed, as a reference to the hard woody capsules.[6]
Conservation
[edit]This species is listed as critically endangered under the Queensland Government's Nature Conservation Act.[1] As of 3 May 2025[update], it has not been assessed by the International Union for Conservation of Nature.
References
[edit]- ^ a b "Species profile—Ristantia pachysperma". Queensland Department of Environment and Science. Queensland Government. 2024. Retrieved 3 May 2025.
- ^ "Ristantia pachysperma". Australian Plant Name Index (APNI). Centre for Australian National Biodiversity Research, Australian Government. Retrieved 3 May 2025.
- ^ a b "Ristantia pachysperma (F.Muell. & F.M.Bailey) Peter G.Wilson & J.T.Waterh". Plants of the World Online. Board of Trustees of the Royal Botanic Gardens, Kew. 2025. Retrieved 3 May 2025.
- ^ a b c Wilson, Peter G. (2022). Kodela, P.G. (ed.). "Ristantia pachysperma". Flora of Australia. Australian Biological Resources Study, Department of Climate Change, Energy, the Environment and Water: Canberra. Retrieved 3 May 2025.
- ^ a b c F.A.Zich; B.P.M.Hyland; T.Whiffen; R.A.Kerrigan (2020). "Ristantia pachysperma". Australian Tropical Rainforest Plants Edition 8 (RFK8). Centre for Australian National Biodiversity Research (CANBR), Australian Government. Retrieved 3 May 2025.
- ^ a b c d Cooper, Wendy; Cooper, William T. (June 2004). Fruits of the Australian Tropical Rainforest. Clifton Hill, Victoria, Australia: Nokomis Editions. p. 354. ISBN 978-0-9581742-1-3.
- ^ a b c d e Wilson, P.G.; Waterhouse, J.T. (1982). "A review of the genus Tristania R. Br. (Myrtaceae): a heterogeneous assemblage of five genera". Australian Journal of Botany. 30 (4): 413–446. doi:10.1071/BT9820413.
- ^ Francis, W.D. (1951). "A Change of Name for a Timber Tree of the Rain Forest of Tropical Queensland". The Queensland Naturalist. 14 (3): 56. Retrieved 7 May 2025.
- ^ Wilson, Peter G. (1980). A Taxonomic Revision of the Metrosidereae (Thesis). Sydney: University of New South Wales. Retrieved 7 May 2025.
External links
[edit]
- View a map of herbarium collections of this species at the Australasian Virtual Herbarium
- View observations of this species on iNaturalist
- View images of this species on Flickriver.com