Hakea incrassata R.Br., Suppl. Prodr. Fl. Nov. Holl. 29 (1830)
T: S of Swan R., [Western Australia], 1827, C.Fraser 19 & 32; syn: BM, CGE (C.Fraser s.n., p.p.).
Hakea leucadendron Meisn., in J.G.C.Lehmann, Pl. Preiss. 1: 572 (1845). T: cataracts at head of Swan River, Western Australia, 25 July 1839, L.Preiss 578; syn: BR, CGE p.p. (as Preiss 241), G, G-DC p.p., HBG, L, LD p.p., NY p.p., NY, M, MEL, MO, P, TCD (as Preiss 241); Quangen, [near Wongamine, E of Toodyay, Western Australia], L.Preiss 568; syn: G, G-DC p.p., LD, LE, MEL, NY; Victoria district, Western Australia, 25 Apr. 1840, L.Preiss 572; syn: LD p.p.; Swan R. to King George Sound, 1843, J.Drummond 1: 603; syn: BM, G, K, LE, MEL, NY p.p., OXF, P.
Low compact shrub, 0.2–1.6 m tall, lignotuberous. Branchlets white-tomentose. Leaves rigid, flat, narrowly obovate, 1.1–8.5 cm long, 3–11 mm wide, usually twisted at base, attenuate above dilated base, entire, rounded or acute apically, appressed-sericeous, quickly glabrescent.
Inflorescence axillary, often arising from old wood, with 6–16 flowers; involucre 4 mm long; pedicels 4–9 mm long, villous, with hairs white or pale brown. Perianth 2 mm long, hirsute, with hairs white or pale brown. Pistil 1.9–2.5 mm long.
Fruit globular with tiny lateral apiculum, 1.7–3.3 cm long, 1.5–3.2 cm wide, smooth or black-pusticulate. Seed 12–20 mm diam.; wing encircling seed body.
Distribution and ecology
Occurs in south-western Western Australia, between Northampton and Ravensthorpe, north of c. 34ºS; usually found in low open heath in sand or sand over quartzite, laterite or gravel.
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.
Derivation of name
From incrassatus, Latin for thickened. It is not clear from the original description just what was being referred to as thickened, but it could have been the stalk supporting the fruit.
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.
The Incrassata group consists of just two species, H. incrassata and H. candolleana , which are probably not each other's closest relatives. Both have flat leaves and tiny flowers with pubescent pedicels and perianths, oblique pollen presenters and woody, sigmoid fruits which are retained on the bushes; the seed body is completely surrounded by a wing. Their closest relations morphologically would appear to be with the Rostrata or the Obliqua groups between which they have been placed in Barker et al. (1999).
The tiny lateral apiculum of the fruit of this species (as in H. platysperma ) suggests that there could be some relationship to the S-shaped fruits of the Rostrata group.
The twisting through 180 degrees of the base of the leaves is usually sufficient to distinguish this species from H. candolleana .
Western Australia: Geraldton highway, 70 mile peg [112 km] from Perth, T.E.H.Aplin 17 (PERTH); Kulin, A.Ashby 149 (PERTH); top of Mt Bakewell, York, A.S.George 3064 (PERTH); 27 km by road SW of Three Springs on Eneabba road, P.S.Short 2412 & L.Haegi (AD, MEL, PERTH).
Link to FloraBase treatment of this species for WA.
More photographs of this species can be seen on the Australian National Botanic Gardens site.
I. Holliday, Hakeas. A Field and Garden Guide 96-7 (2005)
J.A..Young, Hakeas of Western Australia. A Field and Identification Guide 53 (2006)