Banksia densa explained

Banksia densa is a species of column-like shrub that is endemic to Western Australia. It has deeply serrated to pinnatifid leaves, creamy yellow flowers in heads of up to seventy-five, and hairy follicles.

Description

Banksia densa is a shrub, usually with a column-like form that typically grows to a height of but does not form a lignotuber. It has linear, pinnatifid leaves that are long and wide on a petiole up to long. There are between eight and thirteen sharply pointed linear to triangular lobes up to long on each side of the leaves and the lower surface is covered with woolly white hairs. The flowers are arranged in heads of between forty and seventy-five with rusty-hairy or velvety, linear involucral bracts up to long at the base of the head. The flowers have a creamy yellow, hairy perianth or long, depending on subspecies, and a mostly glabrous pistil long or long. Flowering occurs from May to October and the fruit is a hairy, egg-shaped to elliptical follicle long.[1] [2]

Taxonomy and naming

This species was first formally described in 1870 by George Bentham who gave it the name Dryandra conferta and published the description in Flora Australiensis.[3] [4] The specific epithet (conferta) is from a Latin word meaning "crowded".[5]

In 1996, Alex George described two varieties:

In 2007, Austin Mast and Kevin Thiele transferred all Dryandra species to Banksia. As there was already a species named Banksia conferta, Mast and Thiele changed the specific epithet to "densa".[6] [7]

The changed names of the varieties are as follows and are accepted at the Australian Plant Census:

Distribution and habitat

Banksia densa is widespread in inland parts of the south-west of Western Australia, growing in kwongan, woodland and shrubland between Miling, Cadoux the Porongorups, Bodallin and Mount Holland. Variety parva has a more southerly distribution than var. densa.

Ecology

An assessment of the potential impact of climate change on this species found that its range is likely to contract by between 50% and 80% by 2080, depending on the severity of the change.[10]

Conservation status

This banksia is classified as "Priority Two" by the Western Australian Government Department of Parks and Wildlife meaning that it is poorly known and from only one or a few locations.[11]

References

Notes and References

  1. Book: George . Alex S. . Flora of Australia . 17B . 1999 . Australian Biological Resources Study, Canberra . Canberra . 344–346 . 22 April 2020.
  2. George. Alex S.. New taxa and a new infrageneric classification in Dryandra R.Br.. Nuytsia. 1996. 10. 3. 387–388.
  3. Web site: Dryandra conferta. APNI. 22 April 2020.
  4. Book: Bentham . George . von Mueller . Ferdinand . Flora Australiensis (Volume 5) . 1870 . Lovell Reeve & Co/ . London . 578 . 22 April 2020.
  5. Book: Francis Aubie Sharr . Francis Aubie Sharr . Western Australian Plant Names and their Meanings . 2019 . Four Gables Press . Kardinya, Western Australia . 9780958034180 . 168.
  6. Web site: Banksia densa. APNI. 22 April 2020.
  7. Mast. Austin R.. Thiele. Kevin. The transfer of Dryandra R.Br. to Banksia L.f. (Proteaceae). Australian Systematic Botany. 2013. 20. 1. 63–71. 10.1071/SB06016.
  8. Web site: Banksia densa var. densa . Australian Plant Census . 22 April 2020.
  9. Web site: Banksia densa var. parva . Australian Plant Census . 22 April 2020.
  10. Fitzpatrick . Matthew C. . Gove . Aaron D. . Sanders . Nathan J. . Dunn . Robert R. . 2008 . Climate change, plant migration, and range collapse in a global biodiversity hotspot: the Banksia (Proteaceae) of Western Australia . Global Change Biology . 14 . 1–16 . 10.1111/j.1365-2486.2008.01559.x . 6.
  11. Web site: Conservation codes for Western Australian Flora and Fauna. Government of Western Australia Department of Parks and Wildlife. 22 April 2020.