Hymenolepis glabra Magoswana & Magee, 2015

Hymenolepis glabra Magoswana & Magee View in CoL , sp. nov.

Type:— SOUTH AFRICA, Western Cape Province, Montagu (3320): Farm Koktyls, ca. 14 km E of Barrydale (–DD), 4 October 2014, Vlok & Schutte-Vlok 712 (holotype NBG! , isotype K! ).

Erect, much branched shrub to 2 m, single-stemmed at ground level, not sprouting after fire; woody rootstock lacking; branches densely leafy above, glabrous. Leaves alternate, erect to sub-erect, ± equally sized and spaced towards synflorescence, linear to obovate in outline, 10–60 × 1–25 mm, 2- or 3-sect, sometimes entire towards synflorescence, lobes linear, 4–45 × 1–2 mm, terete, acute, margins revolute, coriaceous, glabrous, green. Capitula homogamous, aggregated into open, doubly compound corymbs, peduncles clearly visible, synflorescence 30–80 mm across, bracts lanceolate to linear, 1–6 mm long. Involucre narrowly urceolate, 3–5 mm long; involucre 2- or 3-seriate; involucral bracts 8 or 9, unequal, ovate to lanceolate, 1.0–2.5 × 0.5–1.5 mm, without scarious margins, brownish-gold, glabrous. Receptacle flat, paleate. Florets bisexual, 4 to 6; corolla 2–4 mm long, yellow, sessile-glandular, funnel-shaped, 5- lobed, lobes triangular, spreading; anthers ecaudate and obtuse at base, apical appendages ovate, obtuse; style terete with thickened base, branches truncate, papillate apically. Pappus of basally united, lanceolate scales, 0.5–1.0 mm long. Cypselas oblanceolate to elliptic, 1–2 × 0.4–0.5 mm, 10-ribbed, ribs glabrous, with secretory cavities; nonmyxogenic.

Diagnostic characters: — Hymenolepis glabra shares the glabrous involucre and open doubly compound corymbs ( Fig. 1C View FIGURE 1 ) with H. crithmifolia ( Linnaeus 1771: 424) Greuter et al. (2005: 155) and H. indivisa ( Harvey 1865: 190) Källersjö (1985: 534) and the three are evidently closely related. It can be readily distinguished from both by the 2- or 3-sect leaves sometimes entire towards the synflorescence ( Fig. 1A View FIGURE 1 ). The leaves are uniformly entire in H. indivisa and pinnatisect in H. crithmifolia . Hymenolepis glabra and H. indivisa differ further from the widespread H. crithmifolia by their glabrous stems and foliage and by the erect to suberect leaves with thicker, more terete ultimate leaf segments ( Fig. 1D View FIGURE 1 ). The branches and young leaves in H. crithmifolia are covered with short white hairs, and the leaves are spreading with usually somewhat dorsiventrally flattened ultimate leaf segments.

Distribution and Ecology: — Hymenolepis glabra is currently known from only two localities around Barrydale and Ladismith in the Little Karoo ( Fig. 2 View FIGURE 2 ). At the type locality, the species occurs in small populations of 10 to 20 individuals on quartzitic soils along the southern foothills of the Warmwaterberg, where it is associated with the Warmwaterberg Arid Restioid Fynbos vegetation unit ( Vlok et al. 2005), with Rhodocoma arida Linder & Vlok (1991: 158) ( Restionaceae ) locally abundant to dominant in places and Proteaceae and Ericaceae are rare or absent.

Conservation notes:— No signs of browsing were detected on the species, despite the fact that it is exposed to several game species on the property. We propose a status of Rare due to the limited number of individuals known and the fact that no immediate threats were noted.

Additional specimen examined: — SOUTH AFRICA. Western Cape Province: 3321 (Ladismith): Poort 6 km east of Ladismith on road to Calitzdorp (–CB), 26 October 1975, Taylor 8976 (NBG) .