Acacia validinervia Maiden & Blakely, J. & Proc. Roy. Soc. W. Australia 13: 15; pl. 11, figs 5–8 (1928)
Nyalanyalara , Nyala nyala , Alumaru
Straggly or spindly multistemmed, glabrous shrub 1–4 m high. Branches and branchlets commonly pruinose. Phyllodes elliptic to oblanceolate, sometimes shallowly recurved, 4–13 cm long, 1–4 cm wide, narrowed to (3–) 5–7 mm long pulvinus, obtuse or retuse, thickly or thinly coriaceous; midrib and marginal nerves prominent; lateral nerves distinctly anastomosing; gland 1 or 2, lowermost near base. Racemes 2.5–5 cm long, occasionally longer, 6–14-headed, often pruinose; peduncles 2–5 mm long, stout; heads globular, 5–6 mm diam., densely 40–80-flowered, golden. Flowers 5-merous; sepals united almost to their apices. Pods narrowly oblong, straight or curved, to 12 cm long, 5–10 mm wide, firmly chartaceous to thinly coriaceous. Seeds longitudinal to slightly oblique, oblong to elliptic, 4–7 mm long; funicle 1/2 to completely encircling seed in a single or double fold, creamy yellow.
Widely and disjunctly distributed in desert regions from the Hamersley Ra. area, to the Rudall R. area, W.A., E to the NW margin of the Simpson Desert, N.T., S to the Tomkinson and Musgrave Ra., S.A. Grows in rocky sand, clay and loam, sometimes along dry watercourses.
Several variants are distinguished and future studies based on much more extensive collecting may justify formal recognition of some or all of them.
Typical A.validinervia has thickly coriaceous phyllodes 6–13 x 1.5–4 cm, the lateral nerves forming a prominent reticulum. Its pods are variable judging from few specimens seen: at the E end of the range (near the NW margin of the Simpson Desert) pods are to 12 cm long, c. 8 mm wide, curved, enclosing seeds 7.5–8 x 5 mm; near the W.A./N.T. border, pods are to 7 cm long, 7–8 mm wide, straight, with the seeds (slightly immature) 4–5 x c. 3 mm. Representative specimens:- W.A.: upper Rudall R. area near Curran Curran Rockhole, B.R.Maslin 2139 (CANB, G, K, MEL, NY, PERTH); between Marandoo and Hancock Gorge, N of Mt Bruce, B.R.Maslin 4675 (CANB, PERTH). N.T.: NW Simpson Desert, P.K.Latz 4372 (AD). S.A.: c. 8 km W of Mt Davies, Tomkinson Ra., C.D.Boomsma 41A (AD, PERTH).
Specimens in W.A. from the Little Sandy Desert and the Pilbara region differ from typical A. validinervia in their thinner phyllodes which are often smaller (4–9 x 1–2 cm) and have a less pronounced nerve-reticulum. Pods are curved and 8–10 mm wide (Little Sandy Desert plants: e.g., c. 1 km SE of Curran Curran Rockhole, near Rudall R., A.S.George 10839 , PERTH, TLF) or straight and 5–6 mm wide (Pilbara plants: e.g. between Marandoo and Hancock Gorge, B.R.Maslin 4675 , CANB, PERTH). The Little Sandy Desert plants were included by B.R.Maslin, in J.Jessop (ed.), Fl. Central Australia 132 (1981), as A. steedmanii . Another Little Sandy Desert plant (24 km WSW of Cooma Well, S. van Leeuwen 944 , PERTH) with a whispy habit and atypically long phyllodes (14–18.5 cm) was included by B.R.Maslin, op. cit . 133, as A. affin. validinervia : more material is needed in order to ascertain the status of this entity.
A member of the ‘ A. microbotrya group’ most closely related to A. steedmanii .
Type of accepted name
Cavanagh Ra., W.A., 27 July 1891, R.Helms s.n. ; holo: NSW178738 (2 sheets); iso: AD, K, PERTH.
Synonymy
Acacia notabilis var. validinervia (Maiden & Blakely) J.M.Black, Fl. S. Australia 2nd edn, 3: 534 (1952); Racosperma validinervium (Maiden & Blakely) Pedley, Bot. J. Linn. Soc. 92: 249 (1986). Type: as for accepted name.
Illustrations
J.H.Maiden & W.F.Blakely, loc. cit .; D.J.E.Whibley & D.E.Symon, Acacias S. Australia 2nd edn, 177 (1992).
(BRM)