Acacia ramulosa W.Fitzg., J. Western Australia Nat. Hist. Soc. 2: 15 (1905)
Shrub to 5 m tall, often spreading, with erect foliage. Branchlets with appressed white pubescence between ribs, glabrescent; resinous ribs arising from phyllode bases, with some red-glandular hairs; young tips dark, resinous. Phyllodes linear, terete to flat and thick, 7–15 (–18.5) cm long, 7–5.5 mm wide/diam., striate with thickish longitudinal nerves, appressed pubescent between them. Inflorescences usually single in axils; peduncles 4–15 mm long; spikes 5–30 mm long, dense. Flowers 5- (rarely 6-) merous; sepals oblong, 0.6–1.2 mm long, free or united in tube 0.2–0.5 mm long, with long hyaline hairs on margins; corolla 1.5–2.5 mm long, with long hyaline hairs on lobes, sometimes only on margins; stamens 2.5–4 mm long; ovary with dense appressed long white hairs. Pods not stipitate, cylindrical, abruptly tapered at each end, straight, to 13.5 cm long, 8–10 mm diam. (rarely 5–6 mm diam.), densely appressed silvery-pubescent in between the prominent resinous longitudinal coarsely anastomosing nerves, tardily dehiscent. Seeds longitudinal, oblong in outline, 6–12 mm long, 4–9 mm wide, thick; aril small, terminal, pileate, creamy.
Ranging from Shark Bay, W.A., through S.A. and southern N.T. to central-western Qld and N.S.W. In the central part of its range the species usually occurs on sand on dunes or in sandy loam in swales, occasionally dominant; on the eastern and southern fringes of its range, on shallow stony soils associated with lateritic outcrops; and in the west on deep red sands and loams.
Hybrids with A. aneura occur, particularly in W.A., and are well represented in herbarium collections. Most of these have been identified as A. brachystachya (or in more recently, A. cibaria ) which does not occur in the west of W.A. Also hybridizes with A. craspedocarpa . See A. coolgardiensis .
Two varieties are recognised.
Phyllodes flat to subterete, 1.4–3.5 mm wide; corolla 1.5–2.5 mm long, with long hyaline hairs on lobes or hairs confined to margins; seeds to 12 mm long and 9 mm wide
var . ramulosa
Phyllodes terete, 0.7–1.4 mm diam.; corolla 1.5–1.7 mm long, with hyaline hairs confined to midline of lobes; seeds to 7 mm long and 5 mm wide
var. linophylla
Acacia ramulosa W.Fitzg. var. ramulosa
Bowgada, Horse Mulga
Phyllodes thick, subterete to flat, 7–15 (–18.5 ) cm long, 1.4–3.5 (–5.5) mm wide. Spikes 5–25 mm long. Corolla 1.5–2.5 mm long, with long hyaline hairs on lobes, sometimes confined to margins. Seeds to 12 mm long and 9 mm wide, though over much of the range of the species to 7 mm long and 5 mm wide.
Occurs throughout the range of the species. Flowering Mar.–Sept.; fruiting Sept.–Nov. (a single record in March).
Plants in the extreme west of the species’ range on the Peron Penin. and perhaps the eastern shore of Shark Bay have phyllodes 3–5.5 mm wide, flowers a little larger than is usual for the species over the rest of its range and massive seeds similar in shape to those of Acacia farnesiana , 11–12 mm long and up to 9 mm wide. One of the paralectotypes of A. cibaria (Gasgoyne R., [W.A.] O.Jones s.n. , MEL) probably belongs here.
Type of accepted name
Lennonville, Nov. 1903, W.V.Fitzgerald s.n. ; holo; NSW; iso: PERTH.
Synonymy
Racospermum ramulosum (W.Fitzg.) Pedley, Austrobaileya 2: 354 (1987). Type: as for accepted name.
Representative collections
W.A.: 10 miles [16 km] from Hamelin, C.H.Gittins 1529 (BRI, NSW, PERTH). N.T.: 6.5km SW of Wallara Ranch, J.R.Maconochie 1795 (BRI, DNA, NT, PERTH). S.A.: Olympic Dam, F.J.Badman 2018 (AD, BRI). Qld: c. 45 km WSW of Winton, L.Pedley 5298 (BRI). N.S.W.: Homestead Ck, Mootawingie Natl Park, 17 Sept. 1990, G.J.White s.n. (BRI, CANB, MEL, NSW).
Acacia ramulosa var. linophylla (W.Fitzg.) Pedley (ms), to be published in Appendix to Fl. Australia vol. 11 (2001)
Phyllodes terete, 7.5–13.5 (–16) cm long, 0.7–1.4 mm diam. Spikes 10–30 mm long. Corolla 1.5–1.7 mm long, with long hyaline hairs usually confined to midlines of lobes. Seeds to 7 mm long and 5 mm wide.
Extending from the extreme west of W.A., where it is apparently common, especially in the lower part of the Gascoyne R. basin to S.A., where it occurs sporadically over a wide area. It occurs on sandy soils, often on dunes and on sand-plains, though habitat data are lacking for many of its western occurrences. Associated taxa are reported to be A. ramulosa var. ramulosa and A. aneura .
Acacia atopa possibly originated as a result of hybridism between A. ramulosa var. linophylla and A. subtessarogona .
Type of accepted name
Nannine, Cue, Mt Magnet, W.A., Nov. 1903, W.V.Fitzgerald s.n. ; holo: NSW; iso: PERTH.
Synonymy
Acacia linophylla W.Fitzg., J. Western Australia Nat. Hist. Soc. 1: 16 (1904). Type: as for accepted name.
Representative collections
W.A.: Yalardy Stn, 95 km E of N.W.C.H. [North West Coastal Hwy], B.R.Maslin 5465 (PERTH); 3 miles [5 km] SW of Millrose, N.H.Speck 1377 (BRI, CANB). S.A.: Great Victoria Desert, Serpentine Lakes, 170 km W of Vokes Hill Corner, H.Hewitson (AD, BRI); Barton, C.E.Hubbard 8337 (BRI, K).
(LP)
The information presented here originally appeared on the WATTLE CD-ROM which was jointly published by the Australian Biological Resources Study, Canberra, and the Department of Parks and Wildlife, Perth; it was produced by CSIRO Publishing from where it is available for purchase. The WATTLE custodians are thanked for allowing us to post this information here.
