Wurmbea viridiflora D. Oosthuizen & K. Balkwill 2019, sp. nov.
Creators: name: Oosthuizen, D.
name: Balkwill, K.
Publisher: name: Zenodo
Year: 2019
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Liliopsida
Liliales
Colchicaceae
Wurmbea
Wurmbea viridiflora

description: 2. Wurmbea viridiflora D. Oosthuizen & K. Balkwill, sp. nov. Type: South Africa. Mpumalanga, Lydenburg (2530): 22 km east of Roossenekal, De Berg mountain, in Road Reserve near junction of R577 and D238+, 2231 m (–AA), 1 Mar 2017, Oosthuizen, Balkwill & Kirkel 2463 (J, holo.; BMLH, LYD, K, PRE iso.).
Summer growing geophyte up to 320 mm high when in bloom and 350 mm when in fruit. Corm oblong ovoid, 10–15 mm × 5–10 mm. with brown tunics, produced into a narrow submembraneous flimsy neck, 10–25 mm long. Stem green sometimes light brownish red just above the tunics, 50–180 mm long from the corm to the upper leaf, 1.0– 1.5 mm in diam. Leaves, green, alternating up the stem. Basal leaf solitary, usually erect and somewhat flexuous, green, narrowly linear, 100–300 × 2–4 mm, indistinctly many-veined; apex long attenuate; margin mostly involute to make leaves appear subterete, sometimes flat, entire; base broad, sheathing. Cauline leaves 2, usually erect and somewhat flexuous, indistinctly many-veined; apex attenuate; margin involute to make leaves appear subterete, entire; lower cauline leaf inserted about the middle of the stem, 100–220 mm long, with sheath portion 10–40 mm long; upper cauline leaf inserted 10–25 mm below the flowering spike and up to 60 mm below the fruiting spike, 30–100 mm long with sheathing portion 15–40 mm long. In fl orescence spicate, 3–10-flowered; peduncle 10–40 mm long in bloom and up to 65 mm long in fruit; rachis 15–60 mm long in bloom and up to 90 mm long in fruit, somewhat stout with flowers spaced 2–6 mm apart and fruit up to 15 mm apart, the indeterminate axis often somewhat flexuous and zig-zag in fruit. Perianth: 5 – 6 mm long; tepals 6, stellately spreading, each with 3 veins running from the tip to the base; tube greenish-cream without, cream within, broadly cylindrical gradually widening upwards, 1–2 × 1.5–3.0 mm broad; lobes strongly clawed, diverging, 3–4 mm long; claws cream flushed light greenish cream without, cream within; limbs cream sometimes flushed light greenish cream, margins sometimes involute. Nectary a distinctly raised area largely distal to the point of attachment of the filament, with a gradually declining distal face and a central, 1 mm long, parallel-sided groove in which the filament rests, the inner faces of the proximal ends of the groove touch the filament, indistinctly lighter cream. Filaments white, straight, free section about 2 mm long; anthers violet brown on young flowers turning golden yellow to brownish yellow on older ones, dorsifixed near the base, rounded-oblong; thecae 0.6 × 0.2 mm. Pistil ovary green, rarely with a purple tinge, oblong-elliptic, 4–5 mm long; styles 3, light creamish-green, conical, subulate, 3–4 mm long; stigmas suberect to erect, small, capitate. Capsule oblong to oblong-ovoid, 3- angled, 8–15 × 3–4 mm, about twice as long as perianth remains. Seeds rhomboid with rounded corners, 0.7 × 0.8 mm, slightly compressed, brown with a finely reticulate and shiny surface. Figs. 2, 3, 4.
Etymology: The epithet viridiflora refers to the greenish cream flowers without blotches.
Diagnostic characters: Wurmbea viridi fl ora is similar to W. burrowsii and especially W. angustifolia, but differs from both and from W. elatior in that the flowers are uniformly greenish-cream (Fig. 2C) and do not have the purple bilobed patch distal to the filament on the tepals. Neither W. viridi fl ora nor W. burrowsii have the numerous minute dots or bigger rounded oblong flecks that are usually present on the tepals of W. angustifolia. The tepals of W. viridi fl ora and W. burrowsii have more prominent claws than those of W. angustifolia and W. elatior. Wurmbea viridi fl ora is similar to W. angustifolia in stem height, the length of the leaves and number of flowers on the spikes, but the internodal distances between flowers is shorter in W. viridi fl ora and the pistil of W. viridi fl ora is nearly twice as long as that of W. angustifolia. In addition, W. viridi fl ora has a nectary with a central groove that touches the filament at the base and has a smooth surface, rather than a nectary with a central pocket that is separated from the filament at the proximal end and has a minutely papillate surface as in W. angustifolia.
Distribution & ecology: This taxon is currently known from only two localities in the Steenkampsberg, about 22 km east of Roossenekal (Fig. 4). The vegetation type is Lydenburg Montane Grassland (Gm 18) (Mucina and Rutherford, 2006), where W. viridi fl ora grows in seasonal wetlands or seeps with either sandy soil over a sandstone substrate or humus rich loam at 2230–2250 m (Fig. 2A). It shares these habitats with mosses, sedges and moisture-loving grasses.
Phenology: Flowering specimens have been collected from January through to March.
Conservation notes: The two localities are about 3 km apart, giving an area of occupancy and an extent of occurrence of less than 3 km 2. We estimate the populations to comprise about 400 plants. Additional surveys are required to establish if these are the only populations or whether the species occurs in the nearby Verloren Vallei Nature Reserve that is at slightly lower altitude. At one locality there is encroachment by Acacia mearnsii De Wild (black wattle) and cattle are free to graze the other. We thus propose a provisional threat status of Vulnerable D1, 2 (IUCN, 2012).
3.4. Additional specimens seen
South Africa. MPUMALANGA: 2530 (Lydenburg): Mashishing District, Steenkampsberg, on turnoff to Nederhorst, near the junction of R577 and D238+ roads, 2231 m (− AA), 01 Mar 2017, Balkwill, Oosthuizen & Kirkel 13,972 (E, J, K); On the farm De Berg 71JT, 2240 m (− AA), 18 Jan 2018, Oosthuizen & Balkwill 2905 (BMLH, J, LYD); Balkwill & Oosthuizen 14,149 (J).
description: Published as part of Oosthuizen, D. & Balkwill, K., 2019, Wurmbea (Colchicaceae, Anguillarieae) in Mpumalanga Province, South Africa, including the description of two new species *, pp. 117-123 in South African Journal of Botany 127 on pages 121-122, DOI: 10.1016/j.sajb.2019.08.050, http://zenodo.org/record/10496719