Systematics and ecology of the Australasian genus Empodisma (Restionaceae) and description of a new species from peatlands in northern New Zealand Author Wagstaff, Steven J. Allan Herbarium, PO Box 40 Landcare Research, Lincoln 7640, New Zealand Author Clarkson, Beverley R. Landcare Research, Private Bag 3127, Hamilton 3240, New Zealand text PhytoKeys 2012 2012-07-03 13 39 79 http://dx.doi.org/10.3897/phytokeys.13.3259 journal article http://dx.doi.org/10.3897/phytokeys.13.3259 1314-2003-13-39 FFD7FF88FFAB9757DA70FF94254DB433 576124 3 . Empodisma gracillimum (F.Muell.) L.A.S. Johnson & D.F.Cutler Kew Bull. 28: 383 (1973) Calorophus gracillimus F. Muell., Fragm. Phytogr. Australiae 8 , 88 (1872-74) as ' Calostrophus ' Hypolaena gracillima (F.Muell.) Benth., Fl. Austral. 7 , 239 (1878). Syntypes. ( Fig. 12 ; fide BG Briggs xi.1998), Nouvelle-Hollande, Riv. des cygnes, Preiss JA 1711, 1843. P00748711; Nouvelle-Hollande, Riv. des cygnes, Preiss JA 1714, 1843. P00748712. Figure 12. High resolution photograph of a syntype of Empodisma gracillimum (F.Muell.) L.A.S. Johnson & D.F.Cutler. Mueller (1872-74) originally described the plant as Calorophus gracillimus F.Muell. The specimen, Nouvelle-Hollande, Riv. des cygnes, Preiss JA 1711, 1843, P00748711 is held at HERBARIUM MUSEI PARISIENSIS. The syntype was designated by BG Briggs xi.1998. Etymology. gracillimum describes the slender culms of Empodisma gracillimum . Description. (illustrated in Meney and Pate 1999 ). Culms delicate light green, 55-110 cm in height, 0.5-1.2 mm in diameter, branching profusely. Leaf sheaths, open, closely appressed, 3.5-9.0 mm in length, borne at intervals 25.0-80.0 mm; lamina strongly reflexed from leaf sheath, 2.4-5.0 mm, persistent, light green when young becoming straw coloured. Spikelets light brown, male spikelet 4-5.8 mm, anthers 0.6-1.0 mm long; female spikelet 1.5-2.4 long mm borne on pedicels up to 20 mm long; nutlets approximately 1.4-2.5mm long straw-coloured. 2n = 24. Flowering Aug.-Apr. Comments. Though it approaches Empodisma robustum in height, Empodisma gracillimum is readily distinguished by its more delicate light green culms and shorter leaf sheaths. The male and female spikelets of Empodisma gracillimum are smaller than either Empodisma robustum or Empodisma minus . The female spikelets are solitary and distinctly pedicillate; this character may be a synapomorphy for the species. Representative specimens. Western Australia,Denmark, ♂ and ♀ flowers, B.G. Briggs 8449 & L.A.S. Johnson, CHR525963; Western Australia,4.4 km east Watershed Road, ♂ flowers, A.R. Annels, R.W. Hearn 5112, PERTH04219031; Australia,4.4 km east Watershed Road, fruits, A.R. Annels, R.. Hearn 5111, PERTH04128567; Western Australia,Denmark, ♀ flowers, B.G. Briggs 8449 & L.A.S. Johnson, PERTH01586645; Western Australia,S. of junction with Brockman Highway, ♀ flowers D. Bright, C. Godden & T. Annels SC72.9 PERTH04723732; Western Australia, London Forest Block, 2km S of Mountain Road along Renzo Road, ♂ flowers, R.J. Cranfield & B.G. Ward WFM53, PERTH07102399; Western Australia,Torndirrup National Park, ♂ flowers, G.J. Keighery 8805, PERTH02182831; Western Australia,Darling, ♂ flowers, B.G. Briggs 9330, PERTH06173853; Western Australia,800 m E along O'Byrene Road from intersection of Commonage Road, ♂ flowers, N. Casson & T. Annels SC32.9, PERTH04741110; Western Australia,Walpole-Nornalup National Park, ♀ flowers, A.R. Annels ARA1580, PERTH05466172; Western Australia,Walpole, R.J. Cranfield 10897, PERTH04638530; Western Australia,600 m S of Brockman Highway on Beck Road, ♂ flowers, N. Casson, P. Ellery & C. McChesney SC74.8, PERTH04723775; Western Australia,400 m E of Blackwood and Great North Road, ♂ flowers, R. Davis 7680, PERTH05139317; Western Australia,WA, N. Casson & D. Bright SC106.2, PERTH04749677; Western Australia,S.E. Witchcliff , ♂ flowers, G.J. Keighery 16277, PERTH06330266; Western Australia,NE of Albany, E.M. Sandiford & D.A. Rathbone 1372, PERTH07926855. Distribution. Endemic to western Australia on the coastal plain south of Perth extending along the south coast from Augusta to Albany. Habitat. Grows on peat or sandy nutrient-poor soils. Locally abundant in seasonally or permanently inundated wetlands, swamps and stream margins.