Daviesia rhombifolia Meisner (1844: 56)

Crisp, Michael D., Cayzer, Lindy, Chandler, Gregory T. & Cook, Lyn G., 2017, A monograph of Daviesia (Mirbelieae, Faboideae, Fabaceae), Phytotaxa 300 (1), pp. 448-450 : 448-450

28. Daviesia rhombifolia Meisner (1844: 56) , Bentham (1864: 79), Crisp (1987a: 253) Crisp (1995: 1230), Wheeler et al. (2002: 744). Type: ‘In arenosis sylvae districtus Sussex, d. 17. Dec. 1839, fructifera Herb. Preiss. No. 1145. et in glareosis prope fontem Ronau’swell (Darling’s-range) d. 25. April 1840. No. 1146. (Drummond n. 224.)’ Lectotype (Crisp 1995: 1230): Drummond 224 (BM); isolectotype: G, K (3 sheets), MEL, OXF, P (2 sheets), W (2 sheets). Syntype: Preiss 1145 (LD, NY); isosyntype: G (2 sheets), MEL (2 sheets), MO, P, W. Syntype: Preiss 1146 (LD, NY)

76 • Phytotaxa 300 (1) © 2017 Magnolia Press

CRISP ET AL.

Bushy, spreading shrubs to 0.6 m high, glabrous or hirsute to scabrous on branchlets and phyllodes, glaucous or dull green. Root anatomy normal (unistelar). Branchlets terete, ribbed, hirsute or not. Phyllodes scattered,

A MONOGRAPH OF DAVIESIA

Phytotaxa 300 (1) © 2017 Magnolia Press • 77 spreading, rhombic to transversely so, often undulate, apically acuminate and pungent, distal margins usually crenulate, basally cuneate to truncate and constricted to a short pseudo-petiole, with a thickened articulation at branchlet, 8–30(–35) × 5–25(–35) mm, occasionally scabrous, venation raised, reticulate. Unit inflorescences 1 or 2 per axil, fasciculate, 3(4)-flowered; peduncles 0–0.5 mm long; all bracts forming an involucre at the base of the inflorescence, spreading, recurved, oblong, sometimes slightly keeled, ca. 1 mm long. Pedicels 3–6 mm long. Calyx 3–4.5 mm long including the 1–1.5 mm receptacle, 10-ribbed; upper 2 lobes fully fused into ± trilobed, acute lip ca. 1.5 mm long; lower 3 lobes triangular, ca. 0.5 mm long, usually with a callus at the base of each sinus. Corolla : standard transversely broadly elliptic, emarginate, 5–6 × 5.5–6.5 mm including the 1–1.5 mm claw, with 2 thickened calli at the base of the lamina, orange infused with dark red towards the centre surrounding a barely visible central yellow stripe; wings obovate, auriculate, 4–5.5 × 2–2.5 mm including the 1–2.5 mm claw, orange to red; keel half transversely elliptic, obtuse, auriculate, saccate, broadly rounded along abaxial margin, 4–5.5 × 2–2.5 mm including the 1–1.5 mm claw, red. Stamens strongly dimorphic: inner whorl of 5 with slightly longer, terete filaments and shorter, round, versatile anthers with confluent thecae; outer whorl of 5 with broader, shorter, compressed filaments that become broader towards the apex and longer, slender, basifixed, 2-celled anthers; vexillary stamen with a slender filament that broadens slightly towards the apex and has a smaller anther than the rest; filaments free. Pod obliquely shallowly obtriangular, acuminate, curved briefly and sharply downwards on the lower suture at the base, coriaceous, 12–15 × 9–11 mm; upper suture up-curved to the beak; lower suture broadly rounded but forming an acute angle. Seed not seen. ( Fig. 29 ).

Flowering period:— July to September. Fruiting period: September and October.

Distribution:— Western Australia, rather scattered from Perth to the far south-west and east to Merredin, Lake King and Munglinup.

Habitat:— Grows in white to gravelly sand, gravelly lateritic clay or gravel in open forest dominated by Eucalyptus marginata and E. calophylla , or in kwongan heathland.

Selected specimens (48 examined):—WESTERN AUSTRALIA. Coolgardie : Carrabin , between Merredin and Southern Cross, 31°22’S, 118°40’E , W.E. Blackall 4034, 22 August 1939 ( PERTH). Darling : Gooseberry Hill, Darling Range, 31°57’S, 116°03’E , A. Morrison s.n., 18 August 1903 ( AD 96344237 , CANB 336554 ); ibid ., M. D. Crisp 6705, 24 July 1980 ( AD, CBG, NSW, US); ibid ., R. Helms s.n., 11 October 1899 ( NSW 34906 ). Roe : 17 km E from Newdegate towards Lake King, 33°06’S, 119°12’E , C.E. & D.T. Woolcock D263, 12 August 1982 ( AD, CBG, MEL, PERTH) .

Affinity:— Daviesia rhombifolia differs from all its congeners in the rhombic shape of the phyllodes and the distinctive pods. This species shows some geographic variation, with some specimens from the wheatbelt being hirsute with narrower phyllodes than in the typical, more westerly populations.

Figures

FIGURE 29. Daviesia rhombifolia. A. Flowering branchlet. B. Inflorescence. C. Pod. A, B from Crisp 6705; C from Helms s.n., (NSW 34906). Drawn by A.L. Prowse.