Acacia insolita E.Pritz., Bot. Jahrb. Syst . 35: 310, fig. 36 (1904)
Shrub or subshrub 0.3–1.2 m high. Stems and foliage glabrous or hairy. Stipules 1–4 mm long. Bipinnate leaves usually persistent on mature plants; petiole 5–25 mm long, eglandulose; pinnae normally 1 pair; pinna-rachis 5–40 mm long; pinnules 2–12 pairs, lanceolate to narrowly oblong or elliptic, mostly 5–10 mm long and 1–3 mm wide, acute to subacute, sometimes recurved and concave to conduplicate, green to glaucous. Phyllodes narrowly linear, flat or quadrangular, 1–9 (–15) cm long, 0.5–4 mm wide; midrib prominent or obscure; gland absent. Inflorescences simple and 1 per axil, sometimes false terminal or axillary racemes; peduncles 5–12 mm long, minutely hairy; heads globular, 12–19-flowered, cream to golden. Flowers 5-merous; sepals united, 1-nerved; petals 1-nerved. Pods linear to narrowly oblong, to 8 cm long, 4–7 mm wide, crustaceous, normally reticulate, glabrous; margins thick. Seeds transverse to longitudinal, 3–4 mm long, glossy, dark brown to black, arillate.
Occurs in the Darling Ra. from Wandoo Reserve (c. 65 km NW of Brookton) and Marradong S to Nannup and N of Tonebridge, also Brookton S to Narrogin, south-western W.A.
An unusual species in that, except for subsp. efoliolata , the mature plants retain their juvenile bipinnate foliage. The inflorescences commonly occur singly within the axils of the phyllodes towards the ends of the branchlets, only infrequently do they arise within the axils of the uppermost bipinnate leaves. Typical axillary racemes occasionally develop, but false, terminal racemes (resulting from phyllode suppression) are more frequent. Although A. insolita is commonly placed in the series Pulchellae , fide the original description and P.Guinet et al. , Bot. J. Linn. Soc . 80: 53–68 (1986), it has no close relatives there, fide B.R.Maslin, Nuytsia 1: 478–480 (1975).
Three subspecies are recognised.
1 Bipinnate leaves conspicuous and persistent on mature plants; phyllodes 1- 6 cm long
2 Pinnules flat, green to grey-green
2: Pinnules concave, often conduplicate when dry, recurved, glaucous
1: Bipinnate leaves absent or very few at base of stems on mature plants; phyllodes (2–) 3–9 (–15) cm long
Acacia insolita E.Pritz. subsp. insolita
Shrub 0.3–0.6 cm high. Bipinnate leaves persistent and conspicuous on mature plants; pinna-rachis 2–3 cm long; pinnules 5–12 pairs, flat, green to grey-green. Phyllodes 2–6 cm long, 0.5–2 mm wide, flat; midrib prominent. Flower-heads creamy yellow to golden. Pods 6–7 mm wide, with reticulum obvious ( x10 mag.). Seeds transverse to oblique, circular to elliptic or oblong.
Occurs in the Darling Ra. from Dwellingup and Marradong S to Nannup and N of Tonebridge, also Popanyining- Narrogin area in the adjacent wheatbelt. Grows on laterite mainly in Eucalyptus forest or woodland.
Type of accepted name
Darling Ra., W.A., Aug. 1901, E.Pritzel 1013 ; lecto: K, fide B.R.Maslin, Nuytsia 2: 362 (1979); iso: A, AD, E, G-DC, K, LY, M, MO, NSW, PR, US, W, Z; near Greenbushes, W.A., L.Diels 3835 ; paralecto: n.v.
E.Pritzel, Bot. Jahrb. Syst . 35: 310, fig. 36 (1904); B.R.Maslin, Nuytsia 1: 479, fig. 33 & 492, map 11 (1975).
W.A.: Contine Hill, Dryandra State Forest, G.J.Keighery 9326 (PERTH); Marradong, N.G.Marchant 4 (PERTH); 11.2 km E of Donnybrook on the road to Collie, B.R.Maslin 615 (AD, MEL, NSW, PERTH); Nannup, G.S.McCutcheon 593 (PERTH).
Acacia insolita subsp. recurva Maslin, Nuytsia 12: 363 (1999)
Shrub 0.6–1.2 m high. Bipinnate leaves persistent and conspicuous on mature plants; pinna-rachis 2–4 cm long; pinnules 7–10 pairs, shallowly concave but often conduplicate when dry, recurved, glaucous. Phyllodes 1- 3 cm long, 1- 1.5 mm wide, flat to compressed, thick; midrib not prominent. Flower-heads seemingly golden. Pods 5–6 mm wide, with reticulum obvious (x2 mag.). Seeds transverse, square to oblong.
Known only from the type locality where it grows on a laterite ridge in Eucalyptus woodland with Dryandra nobilis .
Type of accepted name
East Yornaning Nature Reserve, 20 km W of Wickepin, W. A., 4 Sept. 1986, K.J.Atkins 86091 ; holo: PERTH; iso: CANB, K.
W.A.: type locality, B.R.Maslin 6322 (G, MEL, NSW, PERTH).
Acacia insolita subsp. efoliolata Maslin, Nuytsia 12: 362 (1999)
Subshrub 0.4–0.7 m high, with slender, erect or scrambling, glabrous stems. Bipinnate leaves absent or rarely a few at base of stems on mature plants; pinna-rachis 5–10 mm long; pinnules 2 or 3 pairs, flat, subglaucous. Phyllodes (2–) 3–9 (–15) cm long, lower phyllodes usually longer than upper ones, normally 1–4 mm wide, flat with a prominent midrib, sometimes quadrangular when very narrow. Flower-heads golden. Pods 4–7 mm wide, with reticulum obscure. Seeds longitudinal, square to oblong or oblong-elliptic.
Occurs from near Brookton SE to Tuttaning Flora Reserve (c. 25 km due E of Pingelly) and at Wandoo Reserve. Grows on laterite hills.
Because of its non-persistent bipinnate foliage this subspecies is often not readily recognised as belonging to A. insolita . It is sometimes confused with A. flagelliformis which has racemose inflorescences, 6–9-flowered heads, nerveless corolla and absent bracteoles.
Type of accepted name
Pingelly Microwave Repeater Stn, W.A., 6 Aug. 1981, B.R.Maslin 5044; holo: PERTH; iso: CANB, K, NY, PERTH.
W.A.: Tuttaning Reserve, A.S.George 7371 (PERTH); Wandoo Conservation Park, D. Lamont , Aug. 1988 (PERTH); 5 km W of Brookton, P.C.Williams 136 (PERTH).