Acacia congesta Benth., London J. Bot . 1: 327 (1842)
Intricate, spreading shrub 0.5–2.5 m high. Bark dark grey. Branchlets glabrous or hairy, with grey-white epidermis fissured with age. Stipules spinose, sometimes only hardened bases persisting. Phyllodes variable, dimidiate, with abaxial margin straight and adaxial margin shallowly or markedly convex, 5–30 mm long, 3–7 mm wide, pungent, dark green, glabrous or hairy; midrib prominent, normally situated towards lower margin; lateral nerves obscure or pronounced. Inflorescences simple or in short terminal or axillary racemes; peduncles 5–20 mm long, glabrous or hairy, with a bract sometimes above middle; heads globular to obloid, 30–70-flowered, golden. Flowers 5-merous; sepals free. Petals nerveless. Pods moniliform or submoniliform, curved to openly once-coiled, to 6 cm long, 4–5 mm wide, thinly coriaceous-crustaceous to firmly chartaceous, brown to yellow, glabrous. Seeds longitudinal, oblong to ovate or elliptic, 3–5 mm long, dark brown, often minutely rugulose at centre, arillate.
Discontinuous from near Geraldton S to Mogumber and Wongan Hills, south-western W.A.
A variable species, especially with respect to phyllode shape, size and indumentum, and inflorescence morphology. The circumscription of A. congesta was recently changed to include A. cliftoniana and to exclude A. cuneifolia and A. puncticulata , fide B.R.Maslin, Nuytsia 12: 337 (1999). Acacia aculeiformis is seemingly related to this group and A. lullfitziorum is sometimes confused with A. congesta .
Sometimes similar to A. idiomorpha which has more undulate phyllodes with the abaxial margin convex, united sepals, 1-nerved petals and densely pilose to villous, undulate pods. Similar to A. paradoxa which has innocuous phyllodes and more prominent stipules.
Three subspecies are recognised.
Key
1 Phyllodes 10–30 mm long, glabrous or margins and midrib sparsely hirsutellous; heads 35–65-flowered, on axillary peduncles or in racemes
subsp. congesta
1: Phyllodes 5–10 long
2 Phyllodes glabrous, sometimes margins sparsely hairy; heads 50–70-flowered, racemosely arranged
subsp. wonganensis
2: Phyllodes hairy (hairs not restricted to margins or midrib); heads 30–40-flowered, not in racemes
subsp. cliftoniana
Acacia congesta Benth. subsp. congesta
Shrub 0.5–2.5 m high. Branchlets glabrous or sparsely hirsutellous with patent to retrorsely appressed hairs. Phyllodes 10–30 mm long, l:w = 2–5, glabrous or margins and midrib sparsely hirsutellous, slightly shiny, with adaxial margin often slightly angled at the gland. Peduncles 1 per axil or arranged in short racemes, 5–20 mm long, glabrous or sparsely hairy; heads globular or obloid, 35–65-flowered. Pods 5 mm wide. Seeds 4–5 mm long.
Disjunct, occurring in the Geraldton- Northampton, Mingenew- Morawa and the Mogumber- Moora- Pithara areas. Grows on rocky or gravelly hills, in scrub or heath.
Type of accepted name
Swan R., W.A., J.Drummond s.n .; holo: K (herb. Bentham sheet annotated ‘with [Drummond] 161’); iso: K (herb. Hooker sheet).
Synonymy
Acacia collina E.Pritz., Bot. Jahrb. Syst . 35: 291 (1904). Type: E of Mogumber, W.A., 31 Aug. 1901, L.Diels 4043 ; iso: PERTH (Fragment ex B).
Representative collections
W.A.: 24.5 km E of Mingenew on road to Moora, B.R.Maslin 6243 (PERTH); Swan R., J.Drummond 293 (BM, G, K, OXF, P); 1.6 km NE of Nabawa, B.R.Maslin 719 (CANB, MEL, NSW, PERTH); 11 km N from Miling on Great Northern Hwy to Pithara, B.R.Maslin 6210 (PERTH).
Acacia congesta subsp. cliftoniana (W.Fitzg.) Maslin, Nuytsia 12: 338 (1999)
Shrub 0.5–1 m high. Branchlets usually hirsutellous or shortly pilose with patent hairs. Phyllodes 5–10 mm long, l:w = 1.2–2.5, hirsutellous to hirtellous with hairs not restricted to midribs and margins; lateral nerves often pronounced when dry. Peduncles 1–3 per axil, 5–12 mm long, hirsute-hirsutellous; heads globular to shortly obloid, 30–40-flowered. Pods 4–5 mm wide. Seeds 3 mm long.
Occurs from Yandanooka S to near Three Springs. Grows in rocky or lateritic loam in Mallee communities.
Some specimens in the type collection are unusual in having glabrous branchlets and sparsely hairy phyllodes.
Type of accepted name
Arrino, W.A., Sept. 1903, W.V.Fitzgerald s.n .; lecto: NSW 167229, fide B.R.Maslin & R.S.Cowan, Nuytsia 9: 390 (1994); isolecto: NSW 167228, PERTH00744735, 00744743 & 00744727.
Synonymy
Acacia cliftoniana W.Fitzg., J. Western Australia Nat. Hist. Soc . 2 (1): 10 (1904). Type: as for accepted name.
Representative collections
W.A.: c. 13.8 km N of Three Springs towards Mingenew, R.J.Cumming 2157 (MELU, PERTH); c. 6.4 km S of Arrino, B.R.Maslin 734 (PERTH); Yandanooka, 14 Sept. 1904, A.Morrison s.n . (NSW, PERTH).
Acacia congesta subsp. wonganensis Maslin, Nuytsia 12: 338 (1999)
Shrub 1–2 m high. Branchlets hirsutellous to scabridulous with reflexed hairs. Phyllodes 5–9 mm long, l:w = 1.5–3, glabrous or margins sometimes sparsely ciliolate. Peduncles arranged in short racemes, 5–7 mm long, glabrous, infrequently sparsely hirsutellous; heads obloid, 50–70-flowered. Pods 4 mm wide. Seeds 3.5–4 mm long.
Known only from in and around the Wongan Hills. Grows in rocky or lateritic clay or loam in Mallee communities.
Type of accepted name
‘Fowlers Gully’ in the Wongan Hills, W.A., 9 Sept. 1975, B.R.Maslin 3807 ; holo: PERTH; iso: CANB.
Representative collections
W.A.: 12.8 km NW of Wongan Hills towards Piawaning, B.R.Maslin 1637 (MEL, NSW, PERTH); Wongan Hills, near T.V. translator tower, B.R.Maslin 4969 (PERTH); 11.3 km NW of Wongan Hills on road to Piawaning, M.D.Tindale 2791 (K n.v ., NSW, PERTH).
(BRM)
The information presented here originally appeared on the WATTLE CD-ROM which was jointly published by the Australian Biological Resources Study, Canberra, and the Department of Parks and Wildlife, Perth; it was produced by CSIRO Publishing from where it is available for purchase. The WATTLE custodians are thanked for allowing us to post this information here.
