Synonymy
Hakea polyanthema Diels, Bot. Jahrb. Syst. 35: 161 (1904)
T: Greenough R. Crossing, Western Australia, 10 Sept. 1901, L.Diels 6017; ?holo: B.
Description
Dense much-branched shrub, 0.7–1.3 m tall, non-lignotuberous. Branchlets and young leaves appressed-pubescent, ferruginous. Leaves 2.5–5.5 cm long, 0.8–1.2 mm wide, ungrooved; mucro erect.
Inflorescence with 2, 4 or 6 flowers; involucre 1.3 mm long; pedicels 1.5–2.5 mm long, densely appressed-sericeous, with hairs white or cream-yellow, continuing onto claw. Perianth 3.5–4.2 mm long, with hairs white or cream-yellow on claw, ferruginous on limb. Pistil c. 5 mm long; disc of pollen presenter 0.9–1 mm long; gland 1 mm long, erect.
Fruit erect, ovate or obliquely ovate, 2.5–3.5 cm long, 1.5–1.9 cm wide, rugose-reticulate, somewhat corky; beak absent; apiculum 3.5 mm long. Seed 25 mm long, occupying almost whole valve; wing encircling seed body.
Distribution and ecology
Occurs in sand plains south of Geraldton, Western Australia, in open shrubland.
To plot an up to date distribution map based on herbarium collections for this species see Australia's Virtual Herbarium. Localities outside the native range may represent cultivated or naturalised records.
Flowering time
Flowers Sept.
Derivation of name
From poly-, Greek for many and anthemon, Greek for flower, presumably more a reference to the apparent density of the flowers of this species rather than the actual number of flowers.
Relationships
Part of Section Hakea of Bentham (as Euhakea) and characterised by a non-conical pollen presenter, leaves without obvious venation, perianths with or without hairs and fruits with or without horns. Barker et al. (1999) recognised a number of informal morphological groups within the section.
Within this section 5 species were assigned to the informal Obliqua group by Barker et al. (1999). The group is close to the Ceratophylla group, sharing the morphological characteristics of few-flowered inflorescences with pubescent flowers on an obscure rachis, oblique pollen presenters and distinctly woody fruits without horns and usually without beaks and seed in which the wing encircles the seed body; the groups differ in the terete leaves of this group compared with the flat leaves of the Ceratophylla group.
Members of the group are H. adnata, H. brachyptera, H. obliqua, H. polyanthema and H. psilorrhyncha, all from southern WA.
Notes
Only known by a few collections, H. polyanthema is distinguished from H. obliqua by its smaller flowers in which the limb has a rusty tomentum contrasting with white hairs on the claw, and the seed occupies the whole valve. It resembles H. brachyptera in fruit and flowers, and can be difficult to distinguish from it, but H. polyanthema has a larger gland and erect fruit.
Conservation status
This species was recognised as 'Poorly Known' in J.D.Briggs & J.H.Leigh, Rare or Threatened Australian Plants (1995).
In Western Australia denoted as Priority Three - Poorly Known: taxa which are known from several populations, at least some of which are not believed to be under immediate threat (i.e. not currently endangered). Such taxa are under consideration for declaration as ‘rare flora’, but are in need of further survey. (listing current August 2006).
Representative specimens
WA: c. 20 km S of Cliff Head, H.Demarz 1510 (PERTH); On Burma Rd, 16–18 km NW from Midlands Rd, D.B.Foreman 585 (MEL); c. 29 km SE of Walkaway, A.S.George 7862 (PERTH); 7 km S of Eneabba, E.A.Griffin 955 (PERTH); Western Titanium leases, 8 km S of Eneabba, R.Hnatiuk 771279 (PERTH); 11 km S of Irwin, K.Newbey 2111 (PERTH).
Weblinks
Link to FloraBase treatment of this species for WA.
Further illustrations
J.A..Young, Hakeas of Western Australia. A Field and Identification Guide 92 (2006)