Acacia dunnii (Maiden) Turrill, Bull. Misc. Inform. 1922: 299 (1922).
Dunn’s Wattle , Elephant-ear Wattle
Pruinose shrub or tree to 6 m high. Branchlets terete, glabrous. Phyllodes inequilaterally elliptic to ovate, shallowly falcate, 12–42 cm long, 6–17.5 cm wide, very unequal at base, 2–4-times crenate on upper margin, obtuse, coriaceous, glabrous, with 4 or 5 prominent longitudinal nerves confluent with lower margin at base, closely reticulate between main nerves. Inflorescences in terminal or axillary panicles 11–50 cm long; peduncles 8–20 mm long, single or fascicled, glabrous; heads globular, 6–8 mm diam., 50–85-flowered, golden. Flowers 5-merous; sepals 1/4–1/2-united. Pods narrowly oblong, straight, to 17 cm long, 2–4 cm wide, subwoody, coarsely reticulate. Seeds transverse, broadly elliptic to oblong-elliptic, 9–12 mm long, subnitid, brown with brown-black periphery; aril apical.
Occurs in north-western Australia lowlands from Walcott Inlet (W.A.) to Victoria R. (N.T.), extending farther inland along the Ord R. valley to Mabel Downs Stn. Also recorded from some islands near the Kimberley coast. Grows in gravelly soil, often on rocky slopes. Widely cultivated with occasional escapees becoming established in N.T., fide G.J.Leach, Nuytsia 9: 353, 1994.
Maiden formally described A. sericata Benth. var. dunnii based on material collected by E.J.Dunn who published notes in a paper in 1916 ( Proc. Roy. Soc. Victoria 28 (2): 228). Our interpretation is that Turrill, by citing Maiden’s name in synonymy, based A. dunnii on Maiden’s varietal name. The material Turrill cited as just having received in 1922, we interpret as additional to that originally used by Maiden. Given this interpretation, the correct author citation is as given above.
Related to A. platycarpa and A. sericata both of which have considerably smaller phyllodes. As W.B.Turrill, loc. cit ., observed, A. dunnii combines phyllode characters of A. platycarpa with the wingless pods of A. sericata . Also related to A. tolmerensis .
As discussed by B.R.Maslin & L.A.J.Thomson, Austral. Syst. Bot . 5: 729–743 (1992) it is almost certain that Allan Cunningham applied the name A. neurocarpa to the species known today as A. dunnii .
Type of accepted name
Blunder Bay, Victoria R. (c. 10 miles [16 km] above the mouth of Victoria R., fide protologue), N.T., [?22 May] 1913, E.J.Dunn & R.J.Winters ; syn: NSW (4 sheets); isosyn: K.
Acacia sericata var. dunnii Maiden, in A.J.Ewart & O.B.Davies, Fl. N. Terr. 336 (1917). Type: as for accepted name.
Acacia neurocarpa A.Cunn. ex Hook., Icon. Pl. 2: t. 168 (1837) p.p. , not as to lectotype, as to Cambridge Gulf, W.A., Sept. 1819, A.Cunningham 479 (K, NSW ex BM), fide B.R.Maslin & L.A.J.Thomson, Austral. Syst. Bot. : 736 (1992).
W.J.Hooker, loc. cit. , as to the single large phyllode; D.A.Hearne, Trees Darwin N Australia , pl. 1 (1975); J.Brock, Top End Native Pl. 60 (1988).
W.A.: New York Jump Ups, J.R.Maconochie 148 (PERTH); Mabel Downs Stn., Winnama Gorge, E.A.Chesterfield 213 (PERTH); West Governors Is., Napier Broome Bay, 19 May 1984, J.H.Willis (PERTH). N.T.: Victoria R., 25 May 1922, E.J.Dunn (K); 22.5 km W of Timber Ck., A.S.George 6531 (PERTH).
(RSC & BRM)