Xanthophyllum octandrum

Macintyre's boxwood
Flowers seen in Edmonton, Queensland, Jan 2013
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Fabales
Family: Polygalaceae
Genus: Xanthophyllum
Species:
X. octandrum
Binomial name
Xanthophyllum octandrum
Synonyms[4]
  • Macintyria octandra F.Muell.
  • Xanthophyllum macintyrii F.Muell. (nom. illeg.)
  • Banisterodes macintyrii (F.Muell.) Kuntze

Xanthophyllum octandrum, commonly known as Macintyre's boxwood, false jitta, yellow boxwood or sovereignwood, is a slow-growing tree in the milkwort family Polygalaceae which has the potential to reach thousands of years of age. It is endemic to coastal northeastern Queensland, Australia.

Description

Macintyre's boxwood is a large rainforest tree growing up to 30 m (98 ft) in height, with a sparse crown and no buttress roots.[5][6] The leaves are ovate to elliptic and measure up to 22 cm (8.7 in) by 6 cm (2.4 in).[5][6] The inflorescence is a raceme up to 20 cm (7.9 in) long with fragrant zygomorphic flowers on pedicels about 4 mm (0.16 in) long.[5][6] The globular orange fruits are 18 to 23 mm (0.71 to 0.91 in) diameter. The fruit splits along irregular lines to reveal a single seed which is completely enclosed in a black aril.[5][6]

This species is very slow growing and the largest trees in its range are believed to be of great age.[5] One specimen has been radiocarbon dated at 3,500 years old.[7]

Taxonomy

This species was first described in 1865 by the German-born Australian botanist Ferdinand von Mueller as Macintyria octandra. Mueller's description was based on specimens collected by John Dallachy at Rockingham Bay in Queensland, and was published in volume 5 of his work Fragmenta phytographiæ Australiæ.[8][9] Apparently through oversight, Mueller published a second description shortly afterwards in the same year, this time giving it the combination Xanthophyllum macintyrii. The latter is an illegitimate name because it was based on the same type material.[6]

In 1927 the Czech botanist Karel Domin published a new description in Bibliotheca Botanica, giving the species its current binomial combination.[3][4]

Etymology

The genus name Xanthophyllum is a combination of the Ancient Greek words xanthós, "yellow", and fýllo, "leaf", a reference to the colour of aging leaves.[10] The species epithet octandrum is from octo, "eight", and andro, "male". This refers to the eight stamens in the flower.[6]

Distribution and habitat

Macintyre's boxwood grows in well developed rainforest on various soils (but is more common on those derived from grantite), and is found at altitudes from sea level up to 1,600 m (5,200 ft).[5][6]

Treatments of this species in both Flora of Australia and Australian Tropical Rainforest Plants state that it is endemic to Queensland.[5][6] However the Australasian Virtual Herbarium has records of three sightings of the species in a single location in Papua New Guinea, more than 600 km (370 mi) to the northeast of the nearest sighting in Australia.

In Australia it occurs in a number of disjunct populations. The Australasian Virtual Herbarium has records in the following areas (listed from north to south): the tip of Cape York, both close to and within the Apudthama (formerly Jardine River) National Park; in the vicinity of Kutini-Payamu (Iron Range) National Park; a small cluster of sightings near Coen; the largest area with the majority of official sightings, from Cooktown to Lucinda, including the Atherton Tablelands; a cluster in the Paluma Range National Park; two occurrences on Mount Elliot; and the southernmost grouping at Eungella National Park, near Mackay.[11]

Ecology

Fruits of Macintyre's boxwood are eaten by cassowaries (Casuarius casuarius), Sulphur-crested cockatoos (Cacatua galerita), Metallic starlings (Aplonis metallica) and Golden bowerbirds (Prionodura newtoniana).[12] The leaves are eaten by Lumholtz's tree-kangaroos (Dendrolagus lumholtzi).[13]

Conservation

As of 2 January 2023 this species is listed as least concern by both the Queensland Department of Environment and Science and the IUCN.[1][2]

The IUCN cites a wide distribution and no identified current or future threats as the justification for their assessment. It was last assessed by the group on 12 June 2018.[2]

Uses

Extracts of the bark of Xanthophyllum octandrum have shown strong cytotoxic activity, and thus a potential use in pharmacology.[14]

References

  1. ^ a b "Species profile—Xanthophyllum octandrum". Queensland Department of Environment and Science. Queensland Government. 2022. Retrieved 2 January 2023.
  2. ^ a b c IUCN SSC Global Tree Specialist Group & Botanic Gardens Conservation International (BGCI). (2021). "Xanthophyllum octandrum". IUCN Red List of Threatened Species. 2021: e.T192469929A192495308. doi:10.2305/IUCN.UK.2021-1.RLTS.T192469929A192495308.en. Retrieved 2 January 2023.
  3. ^ a b "Xanthophyllum octandrum". Australian Plant Name Index (APNI). Centre for Plant Biodiversity Research, Australian Government. Retrieved 2 January 2023.
  4. ^ a b c "Xanthophyllum octandrum (F.Muell.) Domin". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 2 January 2023.
  5. ^ a b c d e f g F.A.Zich; B.P.M.Hyland; T.Whiffen; R.A.Kerrigan (2020). "Xanthophyllum octandrum". Australian Tropical Rainforest Plants Edition 8 (RFK8). Centre for Australian National Biodiversity Research (CANBR), Australian Government. Retrieved 2 January 2023.
  6. ^ a b c d e f g h Telford, Ian R.H. (2022). Kodela, P.G. (ed.). "Xanthophyllum octandrum". Flora of Australia. Australian Biological Resources Study, Department of Agriculture, Water and the Environment: Canberra. Retrieved 2 January 2023.
  7. ^ Nicholson, N.; Nicholson, H. (2004). Australian Rainforest Plants vol VI. The Channon, NSW: Terania Rainforest Publishing. p. 69. ISBN 0-9589436-6-4.
  8. ^ Ferdinand von Mueller (1865). Fragmenta phytographiæ Australiæ. Vol. 5. p. 8.
  9. ^ "Macintyria octandra F.Muell". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 2 January 2023.
  10. ^ Telford, Ian R.H. (2022). Kodela, P.G. (ed.). "Xanthophyllum octandrum". Flora of Australia. Australian Biological Resources Study, Department of Agriculture, Water and the Environment: Canberra. Retrieved 2 January 2023.
  11. ^ "Search: species: Xanthophyllum octandrum | Occurrence records | The Australasian Virtual Herbarium". Australasian Virtual Herbarium. Australian Government. Retrieved 2 January 2023.
  12. ^ Cooper, Wendy; Cooper, William T. (June 2004). Fruits of the Australian Tropical Rainforest. Clifton Hill, Victoria, Australia: Nokomis Editions. p. 560. ISBN 9780958174213.
  13. ^ "Planting for Wildlife". Trees for the Evelyn and Atherton Tablelands. Retrieved 2 January 2023.
  14. ^ Setzer, Mary C.; Setzer, William N.; Jackes, Betsy R.; Gentry, Glenn A.; Moriarity, Debra M. (2001). "The Medicinal Value of Tropical Rainforest Plants from Paluma, North Queensland, Australia". Pharmaceutical Biology. 39 (1): 67–78. doi:10.1076/phbi.39.1.67.5944. S2CID 86554753.