Acacia heteroclita Meisn., in J.G.C.Lehmann, Pl. Preiss . 1: 18 (1844).
Shrub or small tree 1–4 m high. New growth usually yellow-sericeous. Branchlets compressed to terete, glabrous or sparsely appressed-puberulous. Phyllodes patent to ascending, linear to oblanceolate-linear, curved, mostly (3.5- ) 5–11 cm long, (2–) 3–9 mm wide, arcuately long-acuminate, coriaceous, appressed-puberulous at first, often glabrescent except at apex, with usually 3 strongly raised main nerves with anastomoses present or absent inbetween; gland 1.5–10 (–25) mm above pulvinus. Inflorescences simple, 1 or 2 per axil; peduncles 5–12 mm long, appressed-puberulous to glabrous; heads globular, 4–6 mm diam., 25–60-flowered, densely congested, golden. Flowers 5-merous; sepals free, spathulate; petals partly united. Pods narrowly oblong to linear, slightly raised over seeds, straight, sometimes undulate, to 8 cm long, 2.5–9 mm wide, glabrous or sparsely appressed-puberulous. Seeds longitudinal, elliptic-oblong, 2.5–6 mm long, dull, indistinctly mottled; aril small.
Occurring sporadically from Kulin S to Porongurup Ra., E to Cape Le Grand Natl Park and nearby islands in south-western W.A.
Related to A. triptycha and A. trinalis and superficially similar to A. obtecta and A. websteri (sect. Juliflorae ). Comprises two subspecies.
Specimens with small phyllodes (3–7 cm long, 2–5 mm wide) and atypically wide pods (7–8 mm) occur in some coastal habitats between Bremer Bay and Recherche Archipelago. This maritime variant occurs within the geographic range of the typical subspecies, however, taxonomically it is not readily accommodated within either subspecies. Further studies are needed to resolve the status of this maritime variant.
Phyllodes (2–) 3–4 mm wide (occasionally to 6 mm in coastal habitats). Pods 2.5–5 mm wide. Seeds 2.5–3.5 mm long, 1.5 mm wide; areole small
subsp. heteroclita
Phyllodes 4–9 mm wide. Pods 7–9 mm wide. Seeds 5.5–6 mm long, 3 mm wide; areole large
subsp. valida
Acacia heteroclita Meisn., in J.G.C.Lehmann subsp. heteroclita
Phyllodes (3–) 5–11 cm long, (2–) 3–4 (–6) mm wide, linear to linear-oblanceolate, with no anastomoses. Flower-heads 4–5 mm diam., 25–41-flowered. Pods to 5.5 cm long, 2.5–5 mm wide. Seeds elliptic-oblong, 2.5–3.5 mm long; pleurogram U-shaped; areole small.
Discontinuous from Kulin S to Fitzgerald R. Natl Park and E to Cape Le Grand Natl Park (including nearby islands of Recherche Archipelago), south-western W.A. In shrubland, mallee or in heath, in white to brown sand, sandy loam or gravelly clay sand, often in saline areas and/or at edge of granite outcrops.
Some duplicates of the Drummond collection cited above are numbered ‘4: 8’ but this number is properly assigned to Acacia nodiflora .
A variant from the Kulin area (e.g. B.R.Maslin 3838 , AD, G, NSW, PERTH) has unusual phyllode venation in that one or other, or both the lateral nerves fail to develop or are not evident. Plants in coastal habitats at Bremer Bay and on islands of the Recherche Archipelago tend to have slightly shorter than normal phyllodes (3–7 cm long) which may reach 6 mm wide; furthermore, sometimes their new growth is silvery instead of the characteristic golden-sericeous (e.g. K.Newbey 4276 , PERTH).
The typical subspecies and A. triptycha are very similar in appearance; both have flat, 3-nerved phyllodes and very similar flowers and fruits; however, the phyllodes of A. triptycha are generally narrower. Also allied to the more northern A. trinalis .
Type of accepted name
Cape Riche, W.A., 19 Nov. 1840, L.Preiss 938 ; lecto: LD, fide B.R.Maslin & R.S.Cowan, Nuytsia 9: 406 (1994); isolecto: G, NY, PERTH.
Synonymy
Acacia trissoneura F.Muell., Fragm . 4: 6 (1863). Type: Gairdner Ra., Fitzgerald R., W.A., G.Maxwell ; holo: MEL; iso: K, MEL.
Illustrations
F. von Mueller, Iconogr. Austral. Acacia dec. 7 [pl. 9] (1887); M.Simmons, Acacias Australia 203 (1981).
Representative collections
W.A.: North Twin Peak Is., Recherche Archipelago, M.I.H. Booker 3682 (PERTH); Swan R., J.Drummond 5:8 (BM, G, K, NSW, OXF, P, PERTH); c. 1 km from Kulin towards Yealering, B.R.Maslin 3835 (BRI, K, MO, PERTH).
Acacia heteroclita subsp. valida R.S.Cowan & Maslin, Nuytsia 12: 424 (1999)
Phyllodes (3.5- ) 5–8 cm long, 4–9 mm wide, narrowly oblong-elliptic to almost linear, with a few anastomoses often evident. Flower-heads 5–6 mm diam., 40–60-flowered. Pods to 8 cm long, 7–9 mm wide. Seeds 5.5–6 mm long; areole large, narrow, more than half seed-length.
Endemic in Porongurup Ra., c. 40 km N of Albany in south-western W.A. Grows in loamy soil on or near granite.
Some duplicates of the Drummond collection cited above are numbered ‘4:11’ but this number is properly assigned to Acacia leptospermoides , fide A.S.George & N.Marchant in an unpublished manuscript on Drummond collection numbers.
A robust form of the species with larger phyllodes, pods and seeds than the typical subspecies; it was referred to by G.Bentham, Fl. Austral . 2: 381 (1864), as a broad-phyllode form.
Type of accepted name
Porongurup Ra., W.A., 26 May 1964, A.S.George 6236 ; holo: PERTH.
Representative collections
W.A.: Devil’s Slide, Porongurup Ra., J.S.Beard 7638 (PERTH); Swan R. Colony, J.Drummond 5:11 (G, K, OXF, P, PERTH).
(RSC)