Bulbostylis albidostricta Veltjen & Goetgh., 2015

Veltjen, Emily, Browning, Jane, Goetghebeur, Paul & Larridon, Isabel, 2015, Bulbostylis albidostricta (Abildgaardieae, Cyperaceae): a new sedge species from Angola, Phytotaxa 201 (3), pp. 221-226 : 222-224

Bulbostylis albidostricta Veltjen & Goetgh. , sp. nov. ( Figs. 1 , 2 ).

Similar to Bulbostylis schlechteri C.B.Clarke , but differs due to its velate white nutlets, translucent margins that result in light coloured glumes, the absence of filamentous-pilose marginal hairs on the glumes and the presence of leaf blades.

Type:— ANGOLA. Benguela Province: Cassipera, 30 km from Chicuma on the way to Capala, 1750 m elevation, collected 13 December 1951, H. & E. Hess 51/253 (holotype ZT!, isotype GENT!).

Small, slender perennial herb. Creeping rhizome, 1.2–2.2 mm thick, cataphylls, 0.4–2.5 cm between consecutive plantlets; cataphylls reddish brown, clearly present on younger plantlets, acuminate. Culms 1–6 per plantlet, 0.3–0.6 mm thick at mid height, 15–40 cm long, longitudinally ribbed, slender and stiffly erect, glabrous. Leaves all basal, filiform, up to 1/3 length of the culm, abaxial face convex and striate with multiple veins, adaxial face concave and smooth; sheaths to 7.2 cm long, brown, often intensely red coloured at base, orifice on both sides with 0 to 10 whitish, slender, translucent hairs of 0.2–2.5 mm long; blades 1.2–4.1 × 0.03–0.05 cm, pale green, apex obtuse. Inflorescence with a solitary terminal spikelet, 4.8–7.9 × 1.2–2.8 mm, ovoid to elliptic, approximately 11–20 closely packed and spirally arranged glumes; rachilla straight; 1–2 empty bracts with a persistent leaf-like, excurrent midrib, lowest empty bract 3.8–7.8 mm long, erect, obtuse; glumes ovate, ca. 2.7–3.5 × 1.3 mm, membranous, acute, reddish to brownish at base and centre, minutely covered with short hairs, margins and apex translucent, margins apilose to sparely hairy with inconspicuous minuscule hairs, midrib 3-nerved and light coloured, terminating in apex, abaxially central nerve excurrent. Flowers bisexual; style trifid, dark coloured, ca. 2.6 mm of which branches ca. 1.3 mm; stamens 3. Nutlets 0.8–1.1 mm long, 0.7–1.1 wide, trigonous, broadly obovoid, outer layer white, velate and removable, pale brown underneath, surface pattern reticulate ( Fig. 3 ), apex truncate with persistent darker bulbous style base.

Distribution and ecology:—Known only from the type collection in the Benguela Province in West Central Angola. Perennial found near stagnant pools of ca. 30–50 cm deep in eroded, deforested areas with annual burns, only a few small shrubs present (dambo wetland). At ca. 1750 m elevation.

Etymology:—The species epithet refers to the whitish colour of the nutlets and the slender stiffly erect culms.

Phenology:—Flowering has been observed in the field in December.

Conservation status:—Following the IUCN Red List Criteria and Categories( IUCN 2012), Bulbostylis albidostricta should be considered as “data deficient”.

Additional specimens examined (related species):— Bulbostylis macra ( Ridley 1884: 150) Clarke (1894: 614) DEMOCRATIC REPUBLIC OF THE CONGO. Haut-Shaba: env. de Tshinsenda, Forêt Kibakabaka, Forêt Claire, 1170 m elevation, 20 November 1969, S. Lisowski 10774 ( BR); Haut-Shaba: Domaine de Muhila, Mont Miseye, Steppe herbacée, 1750 m elevation, 7 November 1970, S. Lisowski 10772 ( BR). MALAWI. Near mount Sochi, 900–1000 m elevation, October 1859, J. Kirk s.n. ( K); Matope: 24 October 1887, L. Scott s.n. ( K). ZIMBABWE. Inyanga: 1700 m elevation, 31 October 1930, T. C. E. Fries, T. Nordlindth & H. Weimarck 2488 ( BR); Mutare: 1100 m elevation, 5 December 1950, N. C. Chase 3161 ( BR). Bulbostylis oritrephes ( Ridley 1884: 155) Clarke (1894: 54) DEMOCRATIC REPUBLIC OF THE CONGO. Ferme Bertrand aux Muhila, 1550 m elevation, October 1945, P. Quarre 7114 ( GENT); Kasai: 1952, Dandoy 229 ( BR); Nioka: 1750 m elevation, 28 March 1978, Lejoly 3333 ( BR); 1300–1900 m elevation, Scaetta 777 ( BR). GUINEA. 17 April 1949, A. Pitot 25 ( K); Sulimania: 20 March 1892, G. F. Scott Elliot 8047 ( K). SIERRA LEONE. Loma Mountains, 14 August 1945, P. Jaeger 986 ( K). SOUTH AFRICA. Natal: Sani Pass Hotel to Sani Pass, km 7, 1650 m elevation, E 29°23’, S 29°37’, 4 February 1982, P. Goetghebeur 4460 ( GENT); Natal: 2828DB, Royal Natal National park, Rugged Glen, 5 December 1989, J. Browning 246 ( GENT); Mpumalanga: 2531 CC, Songimvela Game Reserve, Diepgezet Farm, 7 December 1992, C. Reid 1821 ( GENT). TANZANIA. 1150 m elevation, 7 February 1918. A. Peter 22665 ( K). UGANDA. Ruwenzori Mountains, East side of Lake Albert Edward, 1893, G. F. Scott Elliot 8047 ( K). Bulbostylis rhizomatosa ( Lye 1981: 749) R.W. Haines (1983: 1) DEMOCRATIC REPUBLIC OF THE CONGO. Katanga: 11 km from Elisabethville, 1240 m elevation, 16 December 1965, J. J. Symoens 11715 ( BR, GENT); Katanga: A.Schmitz s.n. ( BR); Kipopo: 25 km NO from Elisabethville, 22 November 1960, A. Schmitz 7039 ( BR, GENT); Kipopo: 10 km SSO from Elisabethville, 16 January 1954, A. Schmitz 4539 ( BR). Bulbostylis schlechteri Clarke (1904: 995) SOUTH AFRICA. Transvaal: Aapies rivier, 1600 m elevation, 5 November 1893, R. Schlechter 3634 ( K, L).

Figures

FIGURE 1. Bulbostylis albidostricta.—A. Habit.—B1, B2 and B3. Inflorescences.—C. Nutlets. From the type specimen H. & E. Hess 51/253.

FIGURE 2. Bulbostylis albidostricta.—A. Detail cataphylls.—B. Detail orifice hairs.—C. Detail of nutlet with removed velate layer. From the type specimen H. & E. Hess 51/253.

FIGURE 3. SEM micrographs of Bulbostylis albidostricta.—A1, A2. Nutlets.—B. Nutlet surface cells—C. glume. From the type specimen H. & E. Hess 51/253.