Acacia ditricha Pedley, Austrobaileya 1: 307 (1980)
Mamoose Tree
Shrub or tree to 5 m high, often spreading or straggly. Bark corky, furrowed. Branchlets with an indumentum of short (to 0.1 mm) and long (to 0.4 or 0.6 mm), ascending to erect hairs that also covers leaf axes, soon becoming corky, yellow-fissured and less hairy. Stipular spines 0.8–5 mm long, often inconspicuous. Leaves: petiole 0.1–0.5 cm long, with a raised gland at base of lowest pair of pinnae; rachis (1.2–) 4–10 (–14) cm long, eglandular; pinnae (5–) 20–45 pairs, (0.4–) 0.7–2 cm long; pinnules (9–) 20–30 pairs, mostly crowded, oblong to narrowly oblong or elliptic, mostly 0.4–1.8 mm long, 0.2–0.7 mm wide, obtuse, concolorous, ciliolate or ciliate, with raised midnerve beneath. Inflorescences simple, 1 or 2 in axils; peduncles 15–40 mm long, with involucel of bracts near middle; heads globular, 20–25-flowered, cream-coloured or yellow. Pods mostly narrowly oblong to cultrate or narrowly elliptic, slightly constricted between seeds, flat but slightly raised over seeds, mostly 3–8 cm long, 10–16 (–18) mm wide, coriaceous to woody, obliquely to longitudinally nerved, pubescent or puberulous, becoming almost glabrous.
Occurs in the Gibb River–Mount Barnett Stns area of the Kimberley region, W.A., from Mainoru Stn S to Tanumbirina Stn, N.T., and Cape York Penin. in the Mitchell R. area, Qld. Grows in open eucalypt woodland, grassland and seasonal Melaleuca swamp, in heavy clay alluvium, sandy loam or stony soils. Flowers recorded Jan.; fruits recorded Feb.–Aug.
Previously confused with A. bidwillii . See also A. douglasica .
Type of accepted name
Cook District: Kowanyama Aboriginal Reserve on the Mitchell R., Qld, Dec. 1977, B.Alpher ; holo: BRI.
Illustration
J.R.Wheeler, in J.R.Wheeler (ed.) et al ., Fl. Kimberley Region 332, fig. 98A, flower only (1992).
Representative collections
W.A.: 41 miles [66 km] SW of Gibb River HS, Kimberleys, J.R.Maconochie 1214 (BRI, CANB, NSW, NT, PERTH). N.T.: near Flora R., S of Dorisvale Stn, R.A.Perry 2833 & M.Lazarides (BRI, CANB, K, NT); Roper Hwy 32 km E of junction with Stuart Hwy, J.T.Waterhouse & B.S.Wannan (NSW, UNSW). Qld: Kowanyama – Topsy Creek, P.Black 657 (BRI); 16.6 km S of Rutland Plains on the track to Inkerman, J.R.Clarkson 9515 & V.J.Neldner (NSW, n.v .: BRI, CANB, MBA).
(PGK)