Acacia deltoidea

Acacia deltoidea
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Fabales
Family: Fabaceae
Subfamily: Caesalpinioideae
Clade: Mimosoid clade
Genus: Acacia
Species:
A. deltoidea
Binomial name
Acacia deltoidea
Occurrence data from AVH
Synonyms[1]

Acacia deltoidea is a species of flowering plant in the family Fabaceae and is endemic to the north of Western Australia. It is a shrub with hairy branchlets, overlapping wedge-shaped, elliptic, egg-shaped or Δ-shaped phyllodes, spherical heads of dark golden yellow flowers and oblong, thinly leathery pods.

Description

Acacia deltoidea is a shrub that typically grows to a height of 1.5–3 m (4 ft 11 in – 9 ft 10 in) and has hairy branchlets. Its phyllodes are overlapping, more or less sessile, wedge-shaped, elliptic, egg-shaped or Δ-shaped with the narrower end towards the base, 6–20 mm (0.24–0.79 in) long and mostly 4–7 mm (0.16–0.28 in) wide. There is a gland on the upper edge and the phyllodes are more or less leathery and more or less sharply pointed. The flowers are borne in a spherical head in axils on a peduncle 6–25 mm (0.24–0.98 in) long, each head 5–6 mm (0.20–0.24 in) in diameter with 56 to 73 dark golden yellow flowers. Flowering time depends on species, and the pods are oblong, up to 42 mm (1.7 in) long and 10–12 mm (0.39–0.47 in) wide, thinly leathery and slightly raised over the seeds. The seeds are about 5 mm (0.20 in) long and dull dark brown with an aril on the end.[2][3][4]

Taxonomy

Acacia deltoidea was first formally described in 1832 by George Don in his book, A General History of Dichlamydeous Plants.[5][6] The specific epithet (deltoidea) means 'shaped like the Greek letter δ', referring to the phyllodes.[7]

In 1990, Richard Cowan and Bruce Maslin described two subspecies of A. deltoidea in the journal Nuytsia, and the names are accepted by the Australian Plant Census:[8]

  • Acacia deltoidea subsp. ampla R.S.Cowan & Maslin[9] has most of its phyllodes broadest below the middle and 5–7 mm (0.20–0.28 in) wide, and flowering occurs in June and July.[3][10][11]
  • Acacia deltoidea A.Cunn. ex G.Don subsp. deltoidea[12] has most of its phyllodes broadest at or above the middle and 4–6 mm (0.16–0.24 in), sometimes 2 mm (0.079 in) wide, and flowering mainly occurs from May to August.[3][13][14]

Distribution

This species of wattle is native to an area in the West Kimberley region of northern Western Australia from along the Bonaparte Archipelago and Napier Broome Bay areas and inland to Kimberley Downs Station, Beverley Springs Station and Phillips Range in the east.[3] It is usually found growing in sandy soils over and around sandstone and quartzite.[13][14][15]

Subspecies ampla is only known from a few places in the Admiralty Gulf area.[10][11][16]

Conservation status

Acacia deltoidea subsp. deltoidea is listed as "not threatened" by the Government of Western Australia Department of Biodiversity, Conservation and Attractions,[15] but subsp. ampla is listed as "Priority Two" ,[16] meaning that it is poorly known and from one or a few locations.[17]

See also

References

  1. ^ a b "Acacia deltoidea". Australian Plant Census. Retrieved 5 September 2025.
  2. ^ Cowan, Richard S.; Kodela, Phillip G. "Acacia deltoidea". Flora of Australia. Australian Biological Resources Study, Department of Climate Change, Energy, the Environment and Water: Canberra. Retrieved 5 September 2025.
  3. ^ a b c d "Acacia deltoidea". World Wide Wattle. Western Australian Herbarium. Retrieved 9 November 2020.
  4. ^ "Acacia deltoidea". FloraBase. Western Australian Government Department of Biodiversity, Conservation and Attractions.
  5. ^ Don, George (1832). A General History of Dichlamydeous Plants. Vol. 2. London. Retrieved 5 September 2025.
  6. ^ "Acacia deltoidea". APNI. Retrieved 5 September 2025.
  7. ^ George, Alex S.; Sharr, Francis A. (2023). Western Australian Plant Names and Their Meanings - A Glossary (fifth ed.). Kardinya: Four Gables Press. p. 182. ISBN 9780645629538.
  8. ^ Cowan, Richard S.; Maslin, Bruce R. (1990). "Acacia Miscellany 2. Species related to A. deltoidea (Leguminosae: Mimosoideae: Section Plurinerves) from Western Australia". Nuytsia. 7 (2): 205–206. Retrieved 5 September 2025.
  9. ^ "Acacia deltoidea subsp. ampla". Australian Plant Census. Retrieved 5 September 2025.
  10. ^ a b Cowan, Richard S.; Kodela, Phillip G. "Acacia deltoidea subsp. ampla". Flora of Australia. Australian Biological Resources Study, Department of Climate Change, Energy, the Environment and Water: Canberra. Retrieved 5 September 2025.
  11. ^ a b "Acacia deltoidea subsp. ampla". Australian Biological Resources Study. Retrieved 6 September 2025.
  12. ^ "Acacia deltoideasubsp. deltoidea". Australian Plant Census. Retrieved 5 September 2025.
  13. ^ a b Cowan, Richard S.; Kodela, Phillip G. "Acacia deltoidea subsp. deltoidea". Flora of Australia. Australian Biological Resources Study, Department of Climate Change, Energy, the Environment and Water: Canberra. Retrieved 5 September 2025.
  14. ^ a b "Acacia deltoidea subsp. deltoidea". Australian Biological Resources Study. Retrieved 6 September 2025.
  15. ^ a b "Acacia deltoidea supsp. deltoidea". FloraBase. Western Australian Government Department of Biodiversity, Conservation and Attractions.
  16. ^ a b "Acacia deltoidea supsp. ampla". FloraBase. Western Australian Government Department of Biodiversity, Conservation and Attractions.
  17. ^ "Conservation codes for Western Australian Flora and Fauna" (PDF). Government of Western Australia Biodiversity, Conservation and Attractions. Retrieved 6 September 2024.