 Habit; Bluff Knoll Rd, Stirlings, WA. Photo © I.Holliday. |
 Leaves, young shoots and a fruit. Photo © W.R.Barker |
 Leaves and inflorescences; note the leaf venation. Photo © W.R.Barker |
 Leaves, very young inflorescences arising from wood, and fruits. Photo © W.R.Barker |
Synonymy
Hakea ambigua Meisn., in J.G.C.Lehmann, Pl. Preiss. 2: 260 (1848)
T: Swan River [?Stirling Ra.], [W.A.], s.d. [1843–44], J.Drummond 3: 277; syn: BM, G, G-DC, K, LE p.p., MEL, NY, OXF, P, TCD; probable syn: K (Herb. Hooker, Drummond s.n.).
Hakea trinervis Meisn., in A.L.P.P. de Candolle, Prodr. 14: 414 (1856). T: Swan River Colony [Swan River to Cape Riche, W.A.], s.d. [1848], J.Drummond 5: 408; syn: BM, CGE p.p., G, K, LE p.p., NY, OXF, P, TCD. An image of the NY type specimen can be seen on the New York Botanical Garden site.
Hakea trinervis Meisn., Hooker's J. Bot. Kew Gard. Misc. 4: 209 (1852), nom. nud.
Description
Erect bushy shrub, 1–3 m tall, non-sprouting. Branchlets tomentose, sometimes patchily glabrescent at flowering. Leaves narrowly elliptic to almost linear, flat, 2–11 cm long, 4–20 mm wide, narrowly cuneate at base, entire or slightly crenate, acute to acuminate; longitudinal veins 3 (–7); secondary veins reticulate, visible.
Inflorescence solitary with 20–30 flowers; pedicels shorter than perianth, glabrous. Perianth pale yellow to cream. Pistil 5.5–8.5 mm long, cream or white; gland present.
Fruit obliquely ovate, 2.3–4 cm long, 1.1–1.5 cm wide, slightly curved at apex, prominently beaked. Seed narrowly ovate, concave towards base abaxially, 13–20 mm long; wing extending fully or partly down one side of body only, black.
Distribution and ecology
Restricted to the Stirling Ra., south-western W.A., where it is widespread on slopes and ridges in rocky quartzitic sandy soil, in woodland-heath.
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.–Oct.
Derivation of name
From ambiguus, Latin for doubtful or ambiguous, presumably a reference to Meisner's expressed doubts about the species and its relationships.
Relationships
Part of the Conogynoides group recognised by Bentham and characterised by a conical pollen presenter, veined leaves, glabrous perianth and fruits without horns.
Within this section 12 species were assigned to the informal Undulata group by Barker et al. (1999). This group of Hakea species was combined morphologically because they all have simple flat leaves with 3-7 prominent longitudinal veins, 10-40 small flowers (with 3-10.5 mm long pistils) and decurved woody fruits.
Members of the group are H. ambigua, H. anadenia, H. dactyloides, H. elliptica, H. falcata, H. ferruginea, H. hastata, H. laevipes, H. loranthifolia , H. neurophylla, H. plurinervia and H. undulata , from the eastern states and from SW WA. The newly described H. oligoneura (Nuytsia 19: 254 (2009) from the SW coast of WA belongs with this group.
Notes
The flowers of H. ambigua are faintly sweetly scented and the perianth generally dries dark brown. It is close to and at times difficult to distinguish from H. falcata (q.v.).
A possible disjunct occurrence of H. ambigua well to the east of its otherwise recorded range is based on the single specimen E.Mullins 64 (CANB), the collecting locality of which (64 km from Esperance to Ravensthorpe) may be erroneous.
Representative specimens
W.A.: c. 6.5 km from Red Gum Springs toward Cranbrook, E.M.Canning 6199 (CANB); The Arrows (N side), E end of Stirling Ra., A.S.George 10421 (PERTH); E slopes of Mt Toolbrunup, Stirling Ra., P.G.Wilson 4232 (AD, PERTH).
Weblinks
Link to FloraBase treatment of this species for WA.
Further illustrations
I. Holliday, Hakeas. A Field and Garden Guide 14-15 (2005)
J.A..Young, Hakeas of Western Australia. A Field and Identification Guide 10(2006)