Acacia umbraculiformis Maslin & Buscumb
WATTLE
Acacias of Australia
Common Name
Western Umbrella Wattle
Family
Fabaceae
Distribution
Occurs in the midwest and northern wheatbelt regions of south-western W.A. where it extends from near Cue and Mount Magnet S to near Koorda and W to near Morawa and N of Mullewa. Possible disjunct occurrence NW of Meekatharra (identity of these specimens is uncertain in absence of pods; see B.R.Maslin & C.Buscumb, Nuytsia 18: 137–138 (2008) for discussion).
Description
Shapely, obconic tree 3–6 (–7) m high, crowns flat-topped to subrounded. New shoots resinous. Branchlets glabrous. Phyllodes wide-spreading, linear to narrowly elliptic, falcately recurved, 5–11 cm long, (2–) 3–7.5 mm wide, rarely a few phyllodes to 2 mm, acute to acuminate with normally ±curved tip, shiny, glabrous, dark green; longitudinal nerves fine, numerous and close together, the central nerve the most evident; marginal nerves red-brown and resinous, or sometimes yellow. Inflorescences mostly simple, 1–4 per axil; peduncles 2–8 (–12) mm long, appressed-hairy to glabrous; heads sub-globular or obloid to cylindrical, 3–10 mm long, golden. Flowers 5-merous; sepals ±free to 1/4 or 1/3 united. Pods narrowly oblong to linear or sub-moniliform, occasionally moniliform, ±straight to prominently curved, 5–16 cm long, 6–9 mm wide, firmly coriaceous-crustaceous to sub-woody, dark brown to blackish, not resinous or with a thin, patchy resin layer; marginal nerve discrete and slightly to moderately thickened, yellow or light brown. Seeds longitudinal, oblong to elliptic, 5–10.5 mm long, 5–6.5 mm wide, somewhat flattened, dark brown to black; aril small, cream to orange-cream when dry.
Habitat
Grows on hill crests or slopes, commonly over granite or sometimes banded ironstone or basalt in Acacia woodland or open shrubland.
Specimens
W.A.: Between Mount Magnet and Cue, W.E.Blackall 77 (PERTH); SE of Paynes Find, B.R.Maslin 6657 (PERTH); 45 km NE of Kalannie, B.R.Maslin 7561 (PERTH); 35 km E of Perenjori, A.A.Mitchell 1533 (PERTH); near Remlap homestead, Washington Rocks, Koorda, R.Storer 355 (PERTH).
Notes
Most closely related to A. quadrimarginea which differs most obviously in having pods that are quadrangular by a distinct, vertical flange along each margin, and often longer flowering spikes. A detailed discussion of differences between the species is given by B.R.Maslin & C.Buscumb, Nuytsia 18: 137 (2008). Their distributions abut in the Meekatharra–Mt Magnet region, but it is not known if they are ever sympatric or intergrade. Also elated to A. lapidosa with which it is sometimes sympatric.
FOA Reference
Flora of Australia Project
Author
J.Reid, B.R.Maslin
This identification key and fact sheets are available as a mobile application:
URL: https://apps.lucidcentral.org/wattle/
© Copyright 2018. All rights reserved.