Heliophila pseudoeximia Al-Shehbaz, 2020

Al-Shehbaz, Ihsan A., 2020, Ten new species in the southern African genus Heliophila (Brassicaceae; Cruciferae), Phytotaxa 434 (1), pp. 65-88 : 79-81

Heliophila pseudoeximia Al-Shehbaz , sp. nov.

Diagnosis:— Heliophila pseudoeximia is easily distinguished from the other glabrous perennial species of Heliophila with pinnatisect leaves and muricate-papillate lower stems by having paired glands at the pedicels and petioles bases, unappendaged lateral filaments and petal bases, narrowly oblong and non-moniliform fruit, and 6–8-ovuled ovary.

Type:— SOUTH AFRICA. [Northern Cape, Namakwa], Richtersveld, Rosyntjiesberg, neck N of Lelieshoek , southern slope to the east with large quartz outcrops, 30 Aug. 1977, 1060 m, Oliver, Tölken & Venter 301 (holotype, PRE-650231; isotype, K). Figure 8 .

Description: —Plants perennial herbs, with woody caudex, not glaucous. Trichomes absent. Stems herbaceous, 5–42 cm tall, terete, erect to ascending, simple or branched at base, glabrous. Lowermost cauline leaves not fleshy, 2–9 cm long; petiole 1–4 cm long; blade pinnatisect, 5–9-lobed, segments linear, 0.8–2.7 cm × 1–5 mm; upper cauline similar to lowermost ones, narrower upwards, base not auriculate, all with a pair of stipule-like glands at node, glabrous, base not decurrent or articulate. Racemes terminal, lax, 17–31-flowered, elongated in fruit, not secund; rachis straight, glabrous; fruiting pedicels with a pair of basal bract-like glands, not articulate at base, glabrous, slender, divaricate, arcuate-descending, curved, persistent, lowermost 1–1.7 cm long; buds oblong. Sepals ascending, oblong, 4–5.5 mm long, glabrous, caducous, membranous margined, not cucullate at apex, not saccate at base. Petals white, broadly obovate, 9–12 × 5–6 mm, ascending, rounded at apex, unappendaged, not papillate; claw absent. Stamens slightly tetradynamous; filaments 3–4 mm long, glabrous at base, unappendaged; anthers oblong-linear, 1.8–2.2 mm long, not apiculate at apex. Nectar glands lateral, median glands absent. Ovary glabrous; ovules 6–8 per ovary. Fruit (immature) silique, capsular, narrowly oblong, ca. 1.7 cm × 3 mm, latiseptate, glabrous, not moniliform, straight along replum, divaricate to descending; valves papery, midvein obscure, lateral veins obscure, margin not thickened; gynophore ca. 0.5 mm long; style in fruit 2–3 mm long, cylindrical, slender, glabrous; stigma entire. Seeds (immature) uniseriate, suborbicular, flattened.

Phenology: —Flowering in August.

Distribution: —Known only from the type locality in Namakwa district of the Northern Cape

Etymology: —The name reflects the similarity to the related Heliophila eximia Marais (1966: 103) .

Habitat: —Well-drained stony clay loam, karoo vegetation.

Discussion: — Heliophila pseudoeximia is most closely related to H. eximia , which it resembles in fruit shape, slender pedicels, presence of gland pairs at bases of petioles and pedicels, and unappendaged lateral filaments and petals. It differs from the latter by being a perennial herb (vs. subshrubs) with basally non-decurrent (vs. decurrent), and pinnatisect, 5–9-lobed leaves with linear segments (vs. undivided or apically palmate and 3–5(–7)-lobed and obovate or subflabellate to spatulate leaves), membranous- (vs. non-membranous)-margined sepals, and 5–7 (vs. 8–14) ovules per ovary.

Figures

FIGURE 8. Heliophila pseudoeximia. A. Plant. B. Sepal. C. Petal. D. Stamen. E. Fruiting pedicel and young fruit. Drawn by Al-Shehbaz from holotype (PRE-6502510).