Acacia truncata (Burm. f.) hort. ex Hoffmanns., Verz. Pfl.-Kult. 34 (1824)
Shrub usually dense and 0.5–2.3 m high. Branchlets ribbed, glabrous to shortly pilose. Stipules usually persistent. Phyllodes often patent, cuneate to obtriangular with a prominent gland-bearing angle on adaxial margin above the middle, obliquely truncate, usually 9–25 mm long and 5–13 mm wide with l:w = 1.5–2.5, scarcely pungent, glabrous; midrib central. Inflorescences extremely reduced 1 (2)-headed racemes; raceme axes 0.5–1 mm long; peduncles 10–18 mm long, to 25 mm long in fruit, rather slender, glabrous; heads globular, 7–16-flowered, pale yellow. Flowers 4-merous; sepals united to near apex, with lobes broadly triangular. Pods linear, curved, to 6.5 cm long, 2–4 mm wide, crustaceous, blackish, normally glabrous; margins thick, yellowish. Seeds longitudinal, oblong to elliptic, 3–3.5 mm long, shiny, brown; aril clavate.
Coastal areas from Leeman S to Myalup, south-western W.A. Usually grows in shallow sand over limestone in coastal heath. Flowers June- Sept.
Two variants, both with caducous stipules, occur between Fremantle and Bunbury. One grows in deep sand on coastal foredunes between Fremantle and Myalup Beach and is characterised by rather large phyllodes, to 4 cm long and 1–1.5 cm wide (e.g. L.Preiss 956 , syntype of A. cuneata var. glabra ). The other occurs in shallow sand over limestone in ‘Tuart’ ( Eucalyptus gomphocephala ) forest near Lakes Clifton and Preston. It grows to 3m high, commonly with an open habit, and has phyllodes longer and narrower than normal, i.e. l:w = 3.5–5 (e.g. 37.5 km S of Mandurah, M.D.Tindale 3917 , PERTH).
Acacia truncata and A. littorea should perhaps be treated as subspecies of the one species. However, A. littorea has caducous stipules and commonly shorter, ascending, pungent phyllodes. It occurs mainly S of Bunbury and flowers from Aug. to Nov. and A. truncata occurs N of Bunbury and flowers from June to Sept. See B.R.Maslin, Nuytsia 2: 311–321 (1978) for further details and for discussion of the nomenclature of these two names.
Possibly one of the first two plants ever collected by Europeans in Australia, fide A.S.George, W. Austral. Naturalist 11: 173 (1971).
Type of accepted name
‘ex Java. D. Kleinhof. Habitat in India’; n.v .; J.A.Murray in Linnaeus, Syst. Veg . 13th edn, 790 (1774).
Synonymy
Adiantum (as ‘Adianthum’) truncatum Burm. f., Fl. Indica 235, t. 66, fig. 4 (1768); Mimosa decipiens K.D . Koenig, Ann. Bot. (Kenig & Sims) 1: 366, t. 8 (1804), excl. desc., nom. illeg . (superfluous: the name Adiantum truncatum was cited as a synonym); Acacia decipiens (K.D.Koenig) R.Br., in W.T.Aiton, Hortus Kew . 2nd edn, 5: 463 (1813); Phyllodoce decipiens (Koenig) Link, Handbuch 2: 132 (1831). Type: as for accepted name.
Acacia cuneata Benth., in S.F.L.Endlicher et al ., Enum. Pl . 42 (1837). Type: Swan R., W.A., C.A. Huegel ; n.v.
Acacia decipiens var. elongata Benth., London J. Bot . 1: 330 (1842). Type: Swan R., W.A., J.Drummond s.n .: ?holo: K.
Acacia cuneata var. glabra Meisn., in J.G.C.Lehmann, Pl. Preiss . 1: 9 (1844). Type: near Fremantle, W.A., 15 Aug. 1839, L.Preiss 956 ; lecto: LD, fide B.R.Maslin & R.S.Cowan, Nuytsia 9: 403 (1994); isolecto: K, NY (also K, MEL, P & PERTH-Fragment ex MEL, but all incorrectly labelled L.Preiss 954 ); paralectotype—see A. littorea .
Acacia cuneiformis Ser., Fl. Pom. Lyon . 19, figs 1–9 (1847). Type: cultivated in France from seed collected in Australia; n.v .
[ Acacia decipiens auct. non (K.D.Koenig) R.Br.: E.G.von Steudel, Nomencl. Bot . 2 (1821)]
Illustrations
N.L.Burman, loc. cit .; K.D.Koenig, loc. cit .; N.C.Seringe, loc. cit .; B.R.Maslin, Nuytsia 2: 316, fig. 17 (1978).
Representative collections
W.A.: Swan R., J.Drummond 297 (BM, G, K, MEL, P, PERTH, W); Leeman, B.R.Maslin 4279 (PERTH); near Fremantle, L.Preiss 957 (FI, G, GOET, HBG, K, L, MEL, P, PERTH, STR, W)
(BRM)