Synonymy
Hakea leucoptera R.Br. subsp. sericipes W.R.Barker, J. Adelaide Bot. Gard. 17: 181 (1996)
T: c. 16 km by road NE of Hungerford on road to Eulo, Warrego district, Qld, 26 Aug. 1988, W.R.Barker 5587; holo: AD; iso: to be distributed.
Hakea longicuspis Hook., in T.L.Mitchell, J. Exped. Trop. Australia 397 (1848). T: subtropical New Holland, 10 Dec. 1846, T.L.Mitchell 449; syn: CGE, K, NY. An image of the NY type specimen can be seen on the New York Botanical Garden site.
?Hakea acacioides Domin, Biblioth. Bot. 89: 592 (1921). T: prope Barcaldine, Queensland, III [Mar.] 1910, K.Domin 2923; syn: PR; K.Domin 2921, as for Domin 2923; syn: PR; K.Domin 2922, as for Domin 2923; syn: PR.
Description
Small shrub or tree 1–8 m high, resprouting from base. Branchlets pubescent, glabrescent. Leaves terete, not grooved, 3.5–10 cm long, 1.3–2 mm wide, white-pubescent, glabrescent; apex porrect or uncinate, with mucro 1.5–5.5 mm long.
Inflorescence of 18–45 flowers; rachis simple, or with 1 or 2 basal buds, 6–14 mm long, white or sometimes also brown appressed-pubescent; pedicels 2–6.5 mm long; pedicel and perianth glabrous or sparsely to moderately densely short-tomentose. Perianth 3–4.5 mm long. Pistil 7–11 mm long.
Fruit 1.7–3.2 cm long, 1–2 cm wide, smooth, sometimes sparsely pusticulate; horns obscure. Seed with wing decurrent half to fully down one side, not to very shortly down other, cream to brown-white, sometimes darker at base.
Distribution and ecology
Occurs in dry areas of central W.A., southern and central Qld, and northern N.S.W., usually in heavy soil.
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 Nov.–Dec.
Derivation of name
From sericum, Latin for silk and ped, Latin for foot, a reference to the silky shining hairs on the inflorescence rachis.
How the infraspecific taxa differ
The two subspecies differ only in the nature of the hairs on the rachis of the inflorescence, those of ssp. leucoptera being white woolly pubescent (raised), while those of ssp. sericepes are shining white or brown and appressed (not raised).
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.
H. leucoptera was treated as part of the Sericea group, a predominantly eastern states group characterised by their simple terete leaves, few-flowered inflorescences, hairy pedicels and solitary, prominently woody fruits, these often markedly verrucose or pusticulate and usually with horns.
Other members of the group are H. actites, H. constablei, H. decurrens, H. gibbosa, H. kippistiana, H. lissosperma, H. macraeana, H. macrorrhyncha, H. ochroptera, H. sericea and H. tephrosperma, predominantly from the eastern states of Australia.
Notes
Specimens of H. leucoptera subsp. sericipes from central W.A. have hairs on the rachis which are not as appressed as those from the eastern States.
Two geographically distinct subspecies are recognised, based on indumentum characters. See W.R.Barker, J. Adelaide Bot. Gard. 17: 180 (1996) for discussion.
Hakea leucoptera and H. tephrosperma are often confused. Initially they can often be distinguished by the mucro, curved in H. tephrosperma and usually porrect in H. leucoptera. H. tephrosperma also has a shorter floral rachis with rust-coloured hairs, and the pedicel and perianth are densely appressed-pubescent with rust and white hairs, while H. leucoptera has a longer floral rachis, often persistent after the flowers have fallen, and the pedicel and perianth are often glabrous. Pubescent flowers in H. leucoptera seem to be confined to S.A. and N.T., and even there in mature flowers it is often only the pedicel and limb of the perianth which have sparse or moderately dense raised white hairs; buds are covered all over with hairs.
Representative specimens
W.A.: 3 km S of Agnew, H.Demarz 7251 (PERTH). Qld: 2 km E of Malvernton (40 km W of Blackall), Yaraka to Blackall road, R.W.Johnson 3025 (BRI); Enniskillen, C.T.White 12413 (BRI). N.S.W.: Moor Ck, Tamworth, Nov. 1909, M.B.E.Sampson (AD, NSW, PERTH).
Weblinks
Link to PlantNET treatment.
Link to FloraBase treatment of this species for WA.
Further illustrations
J.A..Young, Hakeas of Western Australia. A Field and Identification Guide 61 (2006)