Grevillea obliquistigma explained

Grevillea obliquistigma is a species of flowering plant in the family Proteaceae and is endemic to the south-west of Western Australia. It is a spreading shrub with linear leaves, and conical to cylindrical clusters of creamy-white to yellowish cream-coloured flowers, sometimes tinged with pink.

Description

Grevillea obliquistigma is a shrub or small tree that typically grows to a height of . Its leaves are usually linear, long and wide, sometimes divided with two or three linear lobes wide. The edges of the leaves or lobes are rolled under, enclosing most of the lower surface. The flowers are arranged in leaf axils and on the ends of branches, in simple or branched clusters, each branch conical or cylindrical and long. The flowers are creamy-white to yellowish cream-coloured, sometimes tinged with pink, the pistil long. Flowering time varies with subspecies, and the fruit is an oblong to oval follicle long.^[1]

Taxonomy

Grevillea obliquistigma was first formally described in 1943 by Charles Gardner in the Journal of the Royal Society of Western Australia from specimens he collected near Pindar.^{[2] [3]} The specific epithet (obliquistigma) means "slanting stigma".^[4]

In 1994, Peter Olde and Neil Marriott described three subspecies of G. obliquistigma in The Grevillea Book, and the names are accepted by the Australian Plant Census:

• Grevillea obliquistigma subsp. cullenii Olde & Marriott^[5] is a shrub about high with silky-hairy branchlets, leaves about wide, flower clusters about long in September and October, with floral bracts about long and wide.^[6]
• Grevillea obliquistigma subsp. funicularis Olde & Marriott^[7] is a dense, spreading shrub about high with glabrous or silky-hairy branchlets, leaves and lobes wide, flower clusters long from September to December, with floral bracts long and wide.^[8]
• Grevillea obliquistigma C.A.Gardner subsp. obliquistigma^[9] is a dense, spreading shrub or spindly tree high with glabrous or silky-hairy branchlets, leaves and lobes wide, flower clusters long from July to December, with floral bracts long and wide.^[10]

Distribution and habitat

Subspecies cullenii grows in mallee near Laverton and Cosmo Newberry in the Avon Wheatbelt and Great Victoria Desert bioregions, subspecies funicularis in open shrubland between Morawa, Mingenew and Ballidu in the Avon Wheatbelt, Geraldton Sandplains and Yalgoo bioregions, and subsp. obliquistigma is widespread from the lower Murchison River to Mount Magnet and Bullfinch in the Avon Wheatbelt, Coolgardie, Geraldton Sandplains, Murchison and Yalgoo bioregions where it is found in open shrubland.

Conservation status

Subspecies funicularis and obliquistigma of G. obliquistigma are listed as "not threatened" but subsp. cullenii is listed as "Priority Three" by the Government of Western Australia Department of Biodiversity, Conservation and Attractions, meaning that it is poorly known and known from only a few locations but is not under imminent threat.^[11]

See also

• List of Grevillea species

Notes and References

1. Web site: Grevillea obliquistigma . Australian Biological Resources Study, Department of Agriculture, Water and the Environment: Canberra . 29 July 2022.
2. Web site: Grevillea obliquistigma. APNI. 29 July 2022.
3. Gardner . Charles A. . Contributiones Florae Australiae Occidentalis, XI. . Journal of the Royal Society of Western Australia . 1943 . 27 . 169 . 29 July 2022.
4. Book: Sharr . Francis Aubi . George . Alex . Western Australian Plant Names and Their Meanings . 2019 . Four Gables Press . Kardinya, WA . 9780958034180 . 263 . 3rd.
5. Web site: Grevillea obliquistigma subsp. cullenii. Australian Plant Census. 21 July 2022.
6. Web site: Grevillea obliquistigma subsp. cullenii . Australian Biological Resources Study, Department of Agriculture, Water and the Environment: Canberra . 30 July 2022.
7. Web site: Grevillea obliquistigma subsp. funicularis. Australian Plant Census. 30 July 2022.
8. Web site: Grevillea obliquistigma subsp. funicularis . Australian Biological Resources Study, Department of Agriculture, Water and the Environment: Canberra . 30 July 2022.
9. Web site: Grevillea obliquistigma subsp. obliquistigma. Australian Plant Census. 20 July 2022.
10. Web site: Grevillea obliquistigma subsp. obliquistigma . Australian Biological Resources Study, Department of Agriculture, Water and the Environment: Canberra . 20 July 2022.
11. Web site: Conservation codes for Western Australian Flora and Fauna. Government of Western Australia Department of Parks and Wildlife. 30 July 2022.