Austronea olifanta Mart.

Martínez-Azorín, Mario, Crespo, Manuel B., Alonso-Vargas, María Ángeles, Dold, Anthony P., Pinter, Michael & Wetschnig, Wolfgang, 2018, Austronea (Asparagaceae, Scilloideae), a new genus from southern Africa, including the description of seven new species, Phytotaxa 365 (2), pp. 101-129 : 119-121

5. Austronea olifanta Mart. -Azorín, M.B.Crespo, M.Pinter & M.A.Alonso sp. nov. ( Fig. 11 )

Ab Austronea barkerae affinis foliorum characteribus, sed hac diversa nempe foliis minus numerosis 1–4 (nec 3–9), a basi nec angustatis nec pseudopetiolatis, in maturitate glabrescentibus vel fere glabris (nec manifeste pilosis); floribus albidis (nec pallide brunneolis), ovario 2.8–3.1 mm long. (nec ca. 1.8 mm long.) et stylo longiore 1.8–2 mm long. (nec ca. 1 mm long.).

Type:— SOUTH AFRICA. Western Cape. Clanwilliam (3218): ca. 6 km south of Clanwilliam , near Clanwilliam-Citrusdal-Cederberg road crossing (- BB), elev. 124 m, 23 September 2015 (in flower), M. Martínez-Azorín, M. B. Crespo, M. A. Alonso & M. Pinter MMA1170 (holotype, GRA!; isotype, ABH74854 !) .

Herbaceous deciduous geophyte. Bulb hypogeal, solitary, ovoid to subglobose, 11–25 × 10–26 mm, extended into a short hypogeal neck up to 1.5 cm long, with pale brown membranous outer tunics and white fleshy tightly packed inner tunics. Roots fleshy, white, branched, 5–40 × 0.7–1 mm. Leaves 1–4, rosulate, sessile, withered or almost withered at flowering time, aerial portion 15–35 × 2–8 mm, from narrowly lanceolate to ovate-lanceolate with acute apex in young leaves to obovate with obtuse apex in older leaves, flattened, slightly canaliculated, green, somewhat leathery, smooth, young leaves distinctly hairy and ciliate, with somewhat retrorse hairs 0.5–1 mm long, older leaves wider and nearly glabrous, although usually sparsely hairy along the lower portions, prostrate to suberect, with a white hypogeal leaf portion connecting to the bulb neck. Inflorescence nodding in bud, raceme 2–4 mm long, capitate or subcorymbose, with 4–21 flowers; peduncle 9–24 cm long, erect, flexuose, distinctly papillose on the lower half; pedicels 2–5 mm long at anthesis, spreading, smooth; bracts ovate-lanceolate, ca. 1 mm long, clasping the pedicels, spurred, the lowermost with a spur up to 2.5 mm long, membranous, white with a central darker band. Flowers pentacyclic, trimerous, stellate, opening about noon and withering in the evening, only 1–2 flowers open at a time, flower buds white-green; tepals 6, entire, white on the adaxial side with a green longitudinal central band on the abaxial side, slightly glandulous at the apex, biseriate, outer overlapping inner at the base, connate for ca. 1.5 mm to form a cup, free portions patent; outer tepals ovate, 3.8–4.6 × 1.8–2 mm, with margins only slightly revolute at anthesis; inner tepals oblong, 3.7–4.4 × 1.7–1.9 mm, more or less flat. Stamens 6, suberect or slightly spreading, adnate to perigone for ca. 1 mm; filaments white, fleshy, subterete and attenuate to the apex, 2.6–2.8 × 0.4 mm, smooth; anthers yellow, oblong, ca. 1 mm long before dehiscence, dehiscing by longitudinal slits, with yellow pollen. Ovary yellowish to pale green, ovoid, somewhat truncate to the style, 2.8–3.1 × 1.5 mm; style white, columnar, 1.8–2 mm long, slightly contrated at the middle, trigonous in transversal section; stigma small and slightly papillate. Capsule and seeds unknown.

Etymology:—Named after the Olifants River valley where the type locality of A. olifanta is located near Clanwilliam in the Western Cape Province of South Africa.

Phenology:— Austronea olifanta flowers around September in the wild at the type locality and leaves are present in July–August.

Habitat:—This species grows on sandy soil derived from Table Mountain sandstone on rocky ground with open vegetation classified as FFs3 Olifants Sandstone Fynbos, with mean annual precipitation ranging from 250–700 mm, peaking May to August, with 3–10 days of frost per year ( Mucina & Rutherford 2006).

Distribution:— Austronea olifanta is only known from the surroundings of Clanwilliam and Pakhuis Pass in the Western Cape Province ( Fig. 10 ).

Diagnostic characters and taxonomic relationships:— Austronea olifanta is characterized by the 1–4, sessile, lanceolate to obovate, flattened to slightly canaliculate leaves, distinctly hairy in young plants with cilia of 0.5–1 mm long, and almost glabrous in older mature plants but usually shortly hairy along the lower portions; inflorescence subcorymbose on an elongate peduncle; tepals white on the adaxial side with a green central band on the abaxial side, 3.7–4.6 mm long, connate for ca. 1.5 mm to form a cup, and patent free portions. Inflorescence, flower size and morphology of A. olifanta resemble those of several species in the genus, such as A. barkerae , A. ecklonii , A. marginata , A. pulchromarginata , A. trichophylla and A. vermiformis . However, leaf morphology of these species is clearly different ( Manning & Goldblatt 2003, 2007, Martínez-Azorín et al. 2016). Among them, A. trichophylla and A. barkerae show hairy leaves, however A. trichophylla differs from A. olifanta by the single, narrowly linear, thickened leaf and is restricted to the surroundings of Grahamstown in the Eastern Cape Province. The closest species to A. olifanta is A. barkerae with respect to the leaf and flower morphology, but the latter differs by the more numerous (3–)5–7(–9) leaves, which are narrowed into a pseudopetiole, always distinctly hairy at least on the abaxial surface in mature plants, the pale-brownish flowers, smaller ovary ca. 1.8 mm long and shorter style ca. 1 mm long ( Manning & Goldblatt 2003). Moreover, A. barkerae is endemic to the Piketberg Quartz Vygieveld (SKk8)—a very restricted vegetation unit characterised by quartz patches with slightly saline soils, as they are the quartz patches of Knersvlakte, within the succulent karoo unit, whilst A. olifanta is found in sandstone fynbos.

Additional material studied (paratypes):— SOUTH AFRICA. Western Cape. Clanwilliam (3218): Pakhuisberg, Clanwilliam, L. C. Leipoldt ( BOL!) ; Clanwilliam (3218): Karroo hills Pakhuis , also Clanwilliam , common, L. C. Leipoldt ( B100167492 !) ; Clanwilliam (3218): In arenosis prope Clanwilliam , 300 feet, 2 October 1897, H. Bolus 9103 ( BOL!) ; Clanwilliam (3218): Clanwilliam division, N of Citrusdal, 16 October 1935, L. E. Taylor 1225 ( BOL!) .

Figures

FIGURE 10. Distribution of Austronea species in southern Africa. A. linearis Mart.-Azorín et al. (red circle), A. olifanta Mart.-Azorín et al. (blue square) and A. pinguis Mart.-Azorín et al. (yellow triangle).

FIGURE 11. Austronea olifanta Mart.-Azorín et al. from S of Clanwilliam, (type locality), Western Cape, South Africa in flower on 23 September 2015 corresponding to MMA1170 and in leaves on 24 July 2016 corresponding to MMA1490-1491. A. Inflorescence; B. Flowers, frontal and dorsal views; C. Dissected flower in lateral view; D. Plants in flower; E. Withered leaves at flowering time; F. Young plants in leaf; G. Mature plants in leaf. Scale bars: A–C: 5 mm; D–G: 1 cm.