Daviesia nematophylla F.Muell. ex Bentham (1864: 78)

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

69. Daviesia nematophylla F.Muell. ex Bentham (1864: 78) , Crisp (1995: 1213). Type : ‘W. Australia, Drummond , 4th Coll. n. 27; Phillips Ranges , Maxwell. ’ Lectotype (Crisp 1995: 1213): Swan River to King George Sound, Drummond coll. 4 no. 27, 1848 ( K, ex Herb. Bentham); isolectotype: BM, G (2 sheets) , K (2 sheets: ex LINN & Herb. Hooker ) , MEL 79054 , OXF, P (2 sheets) , W . Syntype: Phillips Ranges, on a scrubby hill near Mt. Desmond , G . Maxwell 182, 1861 ( MEL 79053 ); isosyntype: BM

Dense, spreading to ascending shrubs, 0.4–2 m high, glabrous. Root anatomy normal (unistelar). Branchlets ascending, terete, slightly striate when dry. Phyllodes erect, nearly always terete though occasionally compressed and spathulate, straight or gently sinuous, with a slightly recurved, mucronate tip, basally articulate, 12–80 mm long, ca. 1 mm diam. or ca. 1.5 mm broad when not terete. Unit inflorescences 1 per axil, flowers solitary or 2–3 in racemes; peduncle 0.25–0.5 mm long; rachis 0–2 mm long, ending in a sterile bristle up to ca. 1 mm long; subtending bracts spreading, spathulate, hooded, slightly striate, ca. 1 mm long. Pedicels 0.75–1.5 mm long. Calyx 3–4 mm long including the 0.75–1.5 mm receptacle to which it is tapered; upper 2 lobes united in a truncate, emarginate lip, ca. 1 mm long; lower 3 lobes triangular, recurved at tips, ca. 0.75–1 mm long. Corolla : standard transversely elliptic, emarginate, ca. 4.5–5 × 6.5 mm including the 1–1.5 mm claw, yellow with a dark red infusion (fading dark grey) around veins towards the centre surrounding a yellow bilobed central mark; wings obovate, rounded and incurved at the apex but not enclosing the keel, auriculate, ca. 5 × 2.5 mm including the 1.5 mm claw, orange grading to dark red toward base; keel half transversely elliptic, scarcely acute, auriculate, saccate, ca. 4.5–5 × 1.5–2 mm including the 1.5 mm claw. Stamens strongly dimorphic: inner whorl of 5 with longer, slender, terete filaments and shorter, round, versatile anthers with confluent thecae; outer whorl of 5 with shorter, broader, compressed filaments and longer, oblong, basifixed, 2-celled anthers; filaments free. Pod obliquely shallowly obtriangular, acute, somewhat compressed, 5.5–7 × 3.5–5 mm; upper suture sigmoid; lower suture acute. Seed not seen. ( Fig. 69 ).

Flowering period:— September to November. Fruiting period: September to December.

Distribution:— Western Australia, widespread in the wheatbelt and mallee districts from Coorow south to Hopetoun and east as far as a line from Coolgardie to east of Esperance.

Habitat:— Well-drained calcareous or sandy loam, or gravelly sandy soils in Eucalyptus -dominated woodland or heathland.

Selected specimens (59 examined):—WESTERN AUSTRALIA. Irwin: 16 km E of Coorow, opposite Paton’s Dam , 29°50’S, 116°10’E , C. Chapman (86)77, 25 September 1977 ( CBG, PERTH); ibid ., C. Chapman (38 A)77, 7 August 1977 ( CBG, K); 1.8 km NE of Wubin on Paynes Find road, 30°05’S, 116°38’E , R. Coveny 7869 & B. R. Maslin, 28 August 1976 ( CANB, NSW). Avon : Merredin, 31°29’S, 118°17’E , M. Koch 2709, 10 September 1923 ( MEL); 34.4 km ENE of Merredin by road, 31°22’S, 118°35’E , R. Coveny 8345 & B. Habersely, 11 September 1976 ( CANB, NSW); 15 km NE of Kellerberrin , 31°33’S, 117°51’E , M. D. Crisp 6585, 20 July 1980 ( AD, CBG, MEL, NSW, PERTH, US); Kununoppin , 31°07’S, 117°55’E , F. E. Victor 13, 30 December 1916 ( PERTH). Coolgardie : Kangaroo Hills Reserve [ca. 10 km SW of Coolgardie], 31°00’S, 121°06’E , P. G. Ladd 169, 16 October 1990 ( PERTH). Roe : 49 km WNW of Kumarl, on Kumarl–Lake King road, 32°43’S, 121°02’E , T. B. Muir 4351, 10 October 1966 ( MEL); 4 km S of Clear Streak Well, ca. 75 km SE of Norseman , 32°31’S, 122°24’E , K. Newbey 7696, 25 September 1980 ( PERTH). Eyre : 22 km E of Ravensthorpe on Esperance road, 33°44’S, 120°18’E , C.E. & D. T. Woolcock D230, 19 September 1982 ( CBG); 25 km E of Ravensthorpe , 33°36’S, 120°19’E , R. J. Cranfield 1014, 5 November 1978 ( PERTH); Ravensthorpe Range, 11 km SW of Ravensthorpe, 33°38’S, 120°09’E , K. Newbey 566, 21 October 1962 ( PERTH) .

Affinity:— Though similar to D. aphylla , D. benthamii and D. scoparia in its floral and fruiting morphology, and being closely related to the latter two in DNA sequences (clade VII.a, Fig. 1B ), D. nematophylla is readily distinguished from all these and other Daviesia species by its erect, gently sinuous phyllodes that are slender, terete and articulate at the base.

Hybrids:— Daviesia aphylla × nematophylla , D. benthamii × nematophylla . Plants with short leaves (thus resembling D. aphylla ) that are angled upwards (thus resembling D. benthamii ) from near the south coast, e.g. around Ravensthorpe, Hopetoun and along the South Coast Hwy, are most likely hybrids between D. aphylla and D. nematophylla . A population in Ravensthorpe Caravan Park includes plants resembling both of the latter species and segregating intermediates (Crisp 991–997, 8984 and 9334). One individual (Crisp 8984) resembles D. nematophylla morphologically, and both its ITS sequence and its cpDNA sequences cluster with D. nematophylla

A MONOGRAPH OF DAVIESIA

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CRISP ET AL.

in the D. benthamii clade, but its ITS sequence is polymorphic, suggesting a hybrid origin. Hybrids between D. benthamii and D. nematophylla occur 6.5 km east of Merredin along the road to Nungarin (Crisp 9388–9). The individual 9388 resembles D. benthamii morphologically but has polymorphic ITS sequences. The individual 9389 is morphologically intermediate, as is 9391, which has rather short, robust phyllodes compared with typical D. nematophylla . Other putative hybrids between D. aphylla and D. nematophylla have been collected in Frank Hann National Park and near Norseman.

Figures

FIGURE 1A. Phylogeny (part) of Daviesia estimated using maximum likelihood (PHYML) from concatenated sequences of ITS (nrDNA), and ndhF and trnL–trnF (cpDNA). The tree was rooted using the monotypic sister groups Viminaria and Erichsenia (not shown). The informal clade names are used for reference in the taxonomic treatment. Numbers on branches show non-bootstrap support. The tips are labelled with the taxon name and sample accession number.

FIGURE 69. Daviesia nematophylla. A. Flowering branchlet. B. Inflorescence. C. Pod. A, B from Chapman (38A)77; C from Chapman (86)77. Drawn by A.L. Prowse.