Acacia pyrifolia DC., Prodr . 2: 452 (1825)
Kanji Bush
Straggly and open or sometimes dense, glabrous, often pruinose shrub normally to c. 3 m high. Stipules usually spinose, sometimes absent at mature nodes. Phyllodes variable, usually elliptic to orbicular or obovate, 2.5–6 cm long and 1.5–4 cm wide, sometimes larger, slightly undulate, pungent, blue-grey to grey-green or glaucous, infrequently green, coriaceous, with prominent and central midrib, penninerved; minor nerves ultimately anastomosing. Inflorescences racemose, often paniculate at ends of branchlets; raceme axes 3–18 cm long; peduncles normally twinned, 8–21 mm long, often subtended by a reduced secondary phyllode; heads showy, globular, densely 70–80-flowered, bright golden. Flowers 5-merous; sepals free. Pods narrowly oblong, rounded over seeds, shallowly curved to openly once-coiled, to c. 8 cm long, 8–15 mm wide, firmly chartaceous. Seeds transverse to longitudinal, broadly elliptic to ovate, 4–6 mm long, turgid, dull, dark brown, scarcely arillate.
Occurs from Carnarvon and near Meekatharra N to Rudall R. and Wallal Downs Stn, north-western W.A., also in the southern Kimberley region from near Windjana Gorge to near Halls Creek. It is especially common in the Pilbara and occurs on some adjacent islands. Grows in sand or loam, often along watercourses; readily colonises disturbed sites.
Future studies may show that A. morrisonii warrants formal recognition. Plants agreeing with the type of this name are infrequent and occur along watercourses in north-western W.A., e.g. Carnarvon, A.M.Ashby 1523 (PERTH) and Ashburton R. on North West Coastal Hwy, B.R.Maslin 5223 (PERTH). They are characterised by stipules commonly absent or slender and scarcely spinose, branchlets non-pruinose and phyllodes green, elliptic to oblanceolate, thinly coriaceous and 15–20 mm wide. Specimens with various combinations of these characters appear to connect this variant with typical A. pyrifolia. Acacia morrisonii and A. pyrifolia var. morrisonii were described independently and based on different specimens of the same Morrison collection. Both Maiden and Domin referred to Scott. Bot. Rev . 1: 97 (1912) where Morrison informally described the taxon and compared it with ‘A . pyrifolia’ (Morrison’s A. pyrifolia was most probably A. inaequilatera ).
Acacia pyrifolia, A. inaequilatera , A. marramamba and A. strongylophylla are closely related. Some of the characters shared by these species include the following: stipules spinose (sometimes only bases persisting), phyllodes relatively short and broad (l:w = 0.8–3) and pungent, sepals free, arils insignificant or absent, inflorescences (except A. strongylophylla ) long-racemose and pods firmly chartaceous to thinly coriaceous. This ‘A. pyrifolia group’ appears closely related to the ‘ A. victoriae group’.
Type of accepted name
Western Australia [sphalm. ‘in Nova Hollandia orient’], ex herb. P, 1821; holo: G-DC; iso: P; ?iso: BM.
Synonymy
Acacia pyrifolia var. morrisonii Maiden (as ‘morrisoni’), J. & Proc. Roy. Soc. New South Wales 51: 248 (1917). Type: Globe Hill, Ashburton R., W.A., 6 Oct. 1905, A.Morrison ; holo: NSW; iso: CANB, PERTH.
Acacia morrisonii Domin, Biblioth. Bot . 89: 257, t. 38, figs 6–8 (1926). Type: banks of Ashburton R. at Globe Hill, W.A., 6 Oct. 1905, A.Morrison ; holo: K.
Acacia clementii Domin, Biblioth. Bot . 89: 258 (1926). Type: between the Ashburton and De Grey rivers, W.A., E.Clement ; lecto: PR 527758, fide B.R.Maslin, Nuytsia 4: 96 (1982); isolecto: K, PR 527758; between Ashburton and Yule rivers, W.A., E.Clement ; paralecto: K (excl. seed on sheet); Bay of Rest, W.A., Feb. 1818, A.Cunningham s.n .; paralecto: K.
Illustrations
K.Domin, loc. cit. ; F. von Mueller, Iconogr. Austral. Acacia dec. 5 (1887), phyllodes on fruiting specimen more asymmetric than normal; R.Erickson et al., Fl. & Pl. W. Australia 147 (1973); B.R.Maslin, in J.P.Jessop (ed.), Fl. Central Australia 120, fig. 159D (1981); M.Simmons, Acacias Australia 141 (1981).
Representative collections
W.A.: 14.5 km S of Exmouth, K.M.Allan 475 (CANB, K, PERTH); Gascoyne R. South, on Great Northern Hwy between Meekatharra and Newman, M.E.Ballingall 1827 (BRI, MEL, PERTH); 10 km from Dampier towards Karratha, B.R.Maslin 2760 (CANB, K, MEL, PERTH); 18.4 km SSW of Flora Valley Stn, R.A.Perry 2495 & M.Lazarides (K, NSW, PERTH).
(BRM)