Heliophila crasssistyla 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 : 72-79

Heliophila crasssistyla Al-Shehbaz , sp. nov.

Diagnosis:— Heliophila crassistyla is easily distinguished from its congeners with ovoid styles by the perennial habit, fruit to 3.5 cm long, unappendaged petal and filament bases, and simple or trifid oblanceolate to obovate cauline leaves.

Type:— SOUTH AFRICA. Western Cape, Overberg District, Swellendam, “Frans Rietfontein”, near Cape Infanta , 28 Sep. 1959, E. Esterhuysen 28312 (holotype, MO-2834439; isotypes E-00199735, M-0152319, PRE-0409988). Figure 4 .

Description: —Plants perennial herbs, not glaucous, subhirsute throughout. Trichomes straight, 0.2–1.5 mm long. Stems herbaceous, slightly woody at base, 10–35 cm tall, smooth, terete, ascending to decumbent, branched at base and above, sparsely to densely hirsute. Leaves cauline, not fleshy; petiole undifferentiated; blade simple and trifid, oblanceolate to obovate when divided, 1.2–5 × 0.4–2.5 cm, hirsute on both surfaces, base cuneate, not auriculate, not articulate or decurrent, without a pair of stipule-like glands at node, margin entire, apex rounded to acute, subapiculate; lateral lobes of trifid leaves 1–15 × 2–6 mm. Racemes terminal, corymbose, 14–23-flowered, elongated in fruit, not secund; rachis straight, hirsute; fruiting pedicels without a pair of basal bract-like glands, not articulate at base, hirsute to subpilose all around, slender, ascending, straight, persistent, lowermost 8–15 mm long; buds ovoid. Sepals erect, oblong, 4.5–5.5 mm long, hirsute, caducous, not saccate at base, not cucullate. Petals blue, obovate, 9–11 × 5–8 mm, ascending, apex rounded, base unappendaged, not papillate; claw absent. Stamens subequal; filaments 3–4 mm long, glabrous at base, all unappendaged; anthers oblong, 1.5–2 mm long, not apiculate at apex. Nectar glands lateral, Ushaped, median glands absent. Ovary pilose; ovules 18–26 per ovary. Fruit in dehiscent silique, capsular, linear, 2.2–3.5 cm × 2.5–3 mm, latiseptate, puberulent to subglabrous, not moniliform, straight along replum, torulose, subappressed to rachis to ascending; valves papery, midvein and 2 lateral veins obscure, margin not thickened; gynophore obsolete; style in fruit 1–2 × 1.2–1.6 mm, ovoid, stout, glabrous; stigma entire. Seeds uniseriate, orbicular, flattened, wingless, margined, 1.7–2 mm in diam.; margin 0.06–0.12 mm wide, sinus shallow.

Phenology: —Flowering September into November.

Distribution: —Endemic to Overberg District of the Western Cape Province and known thus far only from two collections from the Swellendam municipality.

Etymology: —The species name is derived from the thick styles.

Additional specimen examined (Paratype): — SOUTH AFRICA. West Coast, Overberg District, Swellendam, near Cape Infanta, 28 Sep. 1959, E. Esterhuysen 29352 (BOL-108763).

Habitat: —cliffs above the sea, among rocks.

Discussion: — Heliophila crassistyla is most closely related to H. cinerea Marais (1970: 43) , a coastal sanddune endemic of the City of Cape Town District. Both are perennials with ovoid styles, hirsute indumentum, blue and obovate petals of comparable size, ascending fruiting pedicels, and leaf and pedicel bases lacking the paired nodal glands. From the latter, H. crassistyla is easily distinguished by having none fleshy, non-auriculate cauline leaves at least some of which are trifid, unappendaged petal and filament bases, basally non-saccate and subapicallay non-cucullate sepals 4.5–5.5 mm long, 18–26 ovules per ovary, latiseptate fruit 2.2–3.5 cm long, papery fruit valves obscurely veined, glabrous styles 1–2 mm long, and orbicular seeds 1.7–2 mm long with a narrow margin 0.06–0.12 mm wide. By contrast, H. cinerea has fleshy, subauriculate, undivided cauline leaves, strongly appendaged petal and lateral stamen bases, slightly saccate and apically cucullate sepals 7–10 mm long, 32–40 ovules per ovary, terete fruit 4–10 cm long, thick leathery to corky fruit valves, puberulent styles 2–5 mm long, and oblong to suborbicular seeds 2–3 × 2–3 with a wing 0.3–0.7 mm wide.

Heliophila goldblattii Al-Shehbaz , sp. nov.

Diagnosis:— Heliophila goldblattii is readily distinguished from the annual congeners with petiolate undivided leaves by having unappendaged white petals with purple eye, purple anthers, purple stamens dilated and papillate proximally, and terete, strongly torulose, non-moniliform fruits with straight replum.

Type: — SOUTH AFRICA. Northern Cape, Nama Khoi, Springbok, Wildeperdehoek Pass , along Buffels R., 9 Sep. 1980, Peter Goldblatt 5759 (holotype: MO-2791311; isotypes: B-100299449, C, M-0152335). Figures 5 , 6 .

Heliophila amplexicaulis var. spathulata Sond., Abh. Naturwiss. Verein Hamburg 1: 210. 1846. Described from: “in montibus Camisberge ad Kasparskloof, Elleboogfontein et Geelbekskraal. alt. 3–4000ʹ. (Drège) Floret a Julio in Novembrem.” TYPE: Vorberge der Khamiesberg (as Camisbergen), J. F. Drège s.n. (holotype, S-G8782!; isotypes, B-100153800!, HAL-0118324 n.v., HBG-506108 n.v., HBG-506109 n.v., K!, NY-03377087!, P-00739526!, PRE n.v., SAM-00140530!).

Description: —Plants annual herbs, not glaucous, sparsely short pilose. Trichomes slender, straight or slightly crisped, 0.04–0.12 mm long. Stems herbaceous, slender, 11–30 cm tall, smooth, terete, erect to ascending, simple or several from base, branched above, sparsely pilose. Basal leaves not rosulate, soon withered; cauline leaves not fleshy, sparsely short pilose, undivided; petiole of lowermost leaves to 2.5 cm long, slender, gradually shorter upwards; blade of lowermost and middle broadly oblanceolate to spatulate, 1–4 cm × (2–) 5–8 mm, not auriculate, base attenuate to petiole, without a pair of stipule-like glands at node, entire, gradually smaller upwards; uppermost leaves subsessile or on a petiole to 1 mm long. Racemes terminal, lax, (3–)6–18-flowered, elongated considerably in fruit, not secund; rachis straight, usually sparsely pilose; fruiting pedicels filiform, without a pair of basal bract-like glands, not articulate at base, glabrous distally, sparsely pilose all around proximally, divaricate to descending or strongly reflexed and with somewhat geniculate base, persistent, lowermost 1–1.5 cm long; buds globose. Sepals spreading, broadly ovate, 1.5–2 mm long, membranous, glabrous or with individual trichomes, caducous, apex not cucullate, base not saccate. Petals white with dark purple center, broadly obovate to suborbicular, 2.5–3.5(–4) × 1.5–2.5 mm, spreading, rounded at apex, unappendaged, not papillate; claw obsolete. Stamens slightly tetradynamous; filaments 1–1.5 mm long, purple, glabrous, lateral pair with a papillate appendage above base, median pairs unappendaged; anthers purple, ovate, 0.3– 0.5 mm long, not apiculate at apex. Nectar glands lateral, median glands absent. Ovary sparsely to moderately pilose; ovules 6–10 per ovary. Fruit dehiscent silique, capsular, linear-oblong, 1–1.5 cm × 1.5–2 mm, terete, moderately pilose, not moniliform, straight along replum, torulose, reflexed; valves midvein and lateral veins obscure, margin not thickened; gynophore to 0.2 mm long; style in fruit 2–3.5 mm long, cylindrical, slender, glabrous; stigma entire. Seeds uniseriate, ovoid to subglobose, plump, wingless, not margined, 0.9–1 × 0.6–0.7 mm. 2 n = 22.

Phenology: —Flowering July and August into November.

Distribution: —Endemic to the Namakawa District of the Northern Cape Province in Kamiesberg and Nama Khoi municipalities.

Etymology: —The specific epithet is named in honor of its collector Peter Goldblatt (Johannnesburg: 8 Oct. 1943 -), curator emeritus of South African botany, Missouri Botanical Garden, and the world authority on the family Iridaceae .

Additional specimens examined (Paratype): — SOUTH AFRICA. Northern Cape, Namakawa, Kameisberg, Messelpad Pass , SW of Springbok, summit near Koringhuis / Nuweputs , 26 Aug. 1982, E. G. H. Oliver 7717 ( NBG) ; 15 km SSE from Kamieskroon , 29 Aug. 2018, Lat.: -30.08232944 ; Long.: 18.00201333, P. Trávníček & Z. Chumová 18-608 (MO).

Habitat: —Sandy places, S facing steep slopes and cliffs, shady places below granite rocks along gravel road; 760–1220 m.

Discussion: —Ten species of Heliophila , including H. goldblattii , have bicolored petals in which proximal part differs in color from the rest of the petal and, therefore, creating a distinct center (eye) for the flower. In nine species ( H. bulbostyla P.E.Barnes in Compton (1931: 287), H. coronopifolia Linnaeus (1763: 927) , H. cuneata Marais (1966: 101) , H. filiformis Linnaeus f. (1782: 296) , H. lactea Schlechter (1899: 134) , H. macowaniana Schlechter (1899: 135) , H. rigidiuscula Sonder (1846: 251) , H. schulzii Marais (1966: 106) , and H. tricuspidata Schlechter (1899: 140)) the proximal part of each petal is white or yellow, whereas the rest of the petal is blue, purple, mauve, or rarely pink, and they collectively give the flower a distinct whitish or yellowish center or eye. By contrast, in H. goldblattii each petal is dark purple proximally and the rest of it white, thus giving the flower a dark center or eye, a unique feature in the entire genus.

Heliophila goldblattii is somewhat related to H. amplexicaulis , a species widespread in the Western Cape Province (primarily West Coast District and less so in the Cape Winelands and Central Karoo districts) and Northern Cape Province (Namakwa District in Hantam, Kamiesberg, and Nama Khoi municipalities). From the latter, H. goldblattii is easily distinguished by having exclusively alternate, petiolate cauline leaves attenuate to but never auriculate at base, unappendaged white petals with deep purple center (eye) and 2.5–3.5(–4) × 1.5–2.5 mm, purple filaments 1–1.5 mm long and all with distinctly expanded papillate proximal half, purple anthers 0.3–0.5 mm long, terete and non-moniliform fruit 1–1.5 cm long, straight replum, torulose valves, and ovoid to subglobose plump seeds 0.9–1 × 0.6–0.7 mm. By contrast, H. amplexicaulis has at least the lowermost (1 or)2–7(–10) leaf pairs opposite, always amplexicaul to strongly auriculate and sessile at base, white petals (sometimes fading mauve or pink but without a purple center) 4–8.5 × 2.5–5 mm that are minutely 1-appendaged facing the lateral stamens, white filaments 2–4 mm long that are all slender at proximal half but only the lateral pair appendaged, yellow anthers 0.5–1.5 mm long, latiseptate and strongly moniliform fruit 2–3.5 cm long, constricted replum, non-torulose valves, and oblong, flattened seeds 1.3–1.8 × 0.7–1.4 mm.

Despite the above remarkable differences in leaves, flowers, and fruit between the two species, Sonder (1846) recognized a single species with three varieties, whereas Marais (1970) accepted a single variable species without infraspecific taxa. None of these authors examined fruiting material of the species described here as Heliophila goldblattii , though they examined flowering material of only the type collection of H. amplexicaulis var. spathulata .

What is most puzzling is that Sonder (1846, 1860), followed by Marais (1970) and subsequent authors to the present, placed within a single species two kinds of plants that are extremely different in foliage, floral, and fruit morphologies. There is not a single species in the entire Brassicaceae worldwide that has two “morphs” the first of which has plants with alternate, petiolate cauline leaves, non-moniliform terete fruit, torulose valves, purple anthers, and all filaments basally inflated, papillate, and non-appendaged. The second “morph” has plants with opposite, sessile, amplexicaul to strongly auriculate cauline leaves, moniliform latiseptate fruit, non-torulose valves, yellow anthers, and all filaments basally slender, non-papillate, and with only the lateral pair appendaged. Therefore, it is crystal clear that two well-delimited species.

The choice is either to describe the alternate-leaved plants as a new species based on excellent and complete material, as done here, or to raise Heliophila amplexicaulis var. spathulata to the specific rank despite its terribly fragmentary nature and lack of mature fruits. Sonder (1846, 1860), followed by Marais (1970), listed “ H. spathulata E. Mey. ”, but that name was never validly published. Label of the type collection of H. goldblattii gives an accurate description of the petal and stamen color that proved to be very useful in separating the species from the related H. amplexicaulis ( Fig. 6 ).

Heliophila amplexicaulis var. spathulata was based on collections of Johann F. Drège from at least three nearby localities, as evidenced from Drège’s label of the holotype sheet and Sonder (1846). Except for the duplicates at B and P, which were collected from Geelbekskraal on 26 Aug. 1830 and numbered 3173, there is no way of knowing which other duplicates, including the holotype, was collected from where and when. Therefore, the B and P sheets are tentatively recognized here as isotypes

The chromosome number 2 n = 22, which was made by Drs. Terezie Mandáková and Martin Lysák based on the material collected by Pavel Trávníček and Zuzana Chumová 18-6008 (MO), agrees perfectly well with the other x = 11 taxa of Clade C reported by Mandáková et al. (2012).

Heliophila magaliesbergensis Al-Shehbaz , sp. nov.

Diagnosis:—the species is distinguished by being a slender perennial herbs with muricate-papillate striate stems, decurrent and articulate linear to linear-lanceolate leaves, unappendaged petals and stamens, and erect, lanceolate fruits with obscurely veined valves.

Type:— SOUTH AFRICA. Gauteng, West Rand District, Mogale City, Magaliesberg, near Pretoria, no collection date, [ C. E. B.] Bremekamp & R. G. N. Young 654 (holotype, PRE-0740714). Figure 7 .

Description: —Plants perennial herbs, not glaucous, with a slender woody caudex.Trichomes absent. Stems herbaceous, 24–36 cm tall, arising annually from caudex, current-year growth muricate-papillate in rows, striate-ridged from decurrent leaf bases, slightly angled, erect to ascending, branched above, glabrous. Leaves cauline, not fleshy; petiole undifferentiated; blade simple, linear to narrowly linear-lanceolate, 1.5–4.4 cm × 1–3 mm, margin entire, undivided, not auriculate at base, with a pair of deciduous, stipule-like glands at node, glabrous, base not decurrent, articulate. Racemes terminal, lax, 5–10-flowered, not elongated in fruit, not secund; rachis straight, glabrous; fruiting pedicels with a pair of basal bract-like glands, articulate at base, glabrous, slender, erect to erect-ascending, subappressed to rachis, straight, persistent, lowermost 6–8 mm long; buds oblong. Sepals ascending, oblong, 3.5–4 mm long, glabrous, caducous, not cucullate at apex, not saccate at base. Petals white, narrowly oblanceolate, 6.5–7.5 × 1–1.2 mm, ascending, acute to subobtuse at apex, unappendaged, not papillate; claw absent. Stamens slightly tetradynamous; filaments 3.5–4.5 mm long, glabrous, unappendaged; anthers oblong, 0.9–1 mm long, not apiculate at apex. Nectar glands lateral, median glands absent. Ovary glabrous; ovules 6–8 per ovary. Fruit in dehiscent silique, capsular, lanceolate, 2.2–2.9 cm × 3–3.5 mm, latiseptate, glabrous, not moniliform, straight along replum, not torulose, erect, appressed to rachis, attenuate to apex; valves papery, midvein and lateral veins slightly distinct, margin not thickened; gynophore 0.3–0.8 mm long; style in fruit 4–5 mm long, cylindrical, slender, glabrous; stigma entire. Seeds uniseriate, ovate, flattened, wingless, not margined, 2–2.3 × 1.7–2 mm; sinus broad, shallow.

Phenology: —not known.

Distribution: —known only from the type gathering.

Etymology: —named after the Magaliesberg mountain range from which it was collected.

Habitat: —not recorded.

Discussion: —Although the description of a novelty based on a single specimen is not recommended, the four plants on the holotype sheet clearly indicate a very distinctive species easily distinguished from its congeners, especially the three very widespread species that also grow in Gauteng Province. The holotype of Heliophila magaliesbergensis was misidentified as H. rigidiuscula Sonder (1846: 251) , but the novelty differs from the latter by having articulate (vs. non-articulate) leaves with (vs. without) decurrent bases, 5–10-flowered (vs. 25–75(–90)-flowered) non-secund (vs. secund) fruiting racemes, erect to erect-ascending (vs. horizontal to descending or reflexed) fruiting pedicels 0.6–0.8 [vs. (1.2–)1.5–3(–3.5)] cm long., white (vs. purple, mauve or pink) and narrowly oblanceolate (vs. broadly obovate-orbicular) petals 6.5–7.5 × 1–1.2 mm (vs. 6.5–11(–14) × 4–10(–13) mm) without (vs. with a large papillate) appendage, unappendaged (vs. appendaged) lateral stamens, erect (vs. divaricate to pendulous or reflexed) fruit 2.2–2.9 cm × 3–3.5 mm (vs. (2.5–)3.5–7(–9) cm × 3–8(–10) mm, style 4–5 mm (vs. (2.5–)5–14(–20) mm) long, and wingless (vs. distinctly winged) seeds 2–2.3 × 1.7–2 mm (vs. 4–7.2(–9) × 3.5–6(–7) mm).

The novelty is markedly different from Heliophila carnosa ( Thunberg 1800: 108) Steudel (1840: 742) , the second species growing in Gauteng, by being herbaceous perennial with a short, slender caudex (vs. subshrubs or suffrutescent perennials with elongated woody base) and muricate-papillate-striate (vs. glabrous, non-striate) stems, without (vs. with a well-developed) basal rosette of non-fleshy (vs. fleshy) leaves with slender (vs. strongly thickened) decurrent (vs. non-decurrent) base, fruiting pedicels 0.6–0.8 (vs. 1–3.2) cm long, narrowly oblanceolate (vs. obovate to obovate-orbicular) petals 6.5–7.5 × 1–1.2 mm (vs. 6–13(–16) × 4–9(–13) mm), 6–8 (vs. 14–36) ovules per ovary, and erect (vs. spreading to strongly pendulous) fruit. From H. suavissima Burch. ex Candolle (1921b: 691) , H. magaliesbergensis differs by being a perennial herb with a slender caudex (vs. shrubs, subshrubs, or rarely perennial herbs) with muricate-papillate and striate stems (vs. papillate puberulent, non-striate stems), decurrent and articulate (vs. non-decurrent, non-articulate) leaf bases, white and narrowly oblanceolate petals 6.5–7.5 × 1–1.2 mm (vs. blue to purple or pink and obovate to suborbicular petals (6–)9–15 × (4–) 6–9 mm), 6–8-ovuled (vs. (10–)16–24(–28) ovules per ovary, and erect and non-moniliform (vs. descending to reflexed and submoniliform) fruit 2.2–2.9 cm (vs. (3–)4.5–7(–9) cm) long.

Heliophila magaliesbergensis shows no affinity or relationship to any of the other species of the genus, and it superficially resembles the new species H. volkii (see below), a widely disjunct endemic of the Western Cape, in habit, fruit shape, and muricate-papillate and striate stems. The latter is a shrub (vs. perennial herb) with fascicled (vs. alternate), terete (vs. flattened), fleshy (vs. non-fleshy) leaves adaxially grooved by involute margin (vs. adaxially flat), slightly longer petals 10–12 mm (vs. 6–8 mm), and prominently (vs. obscurely) veined fruit. Using Marais (1970) key to the species of Heliophila , the novelty keys out to H. rimicola , a disjunct subshrub endemic of the Swartberg (Kannaland, Western Cape) with 1–5-flowered intercalary (vs. terminal) fruiting racemes, broadly obovate (vs. narrowly oblanceolate) petals 10–15 × 5–8 mm (vs. 6.5–7.5 × 1–1.2 mm), fruiting pedicels 1–2.5 (vs. 0.6–0.8) cm long, cucullate (vs. non-cucullate) median sepals, and anthers 1.5–2.5 (vs. 0.9–1) mm long.

Figures

FIGURE 4. Heliophila crassistyla. A. Plant. B. Cauline leaves. C. Sepal. D. Petal. E. Fruit and fruiting pedicel. Drawn by Al-Shehbaz.A, B from isotype (E-00199735), C, D from isotype (M-0152319), E from isotype (PRE).

FIGURE 5. Heliophila goldblattii. A. Plant. B. Cauline leaf. C. Sepal. D. Petal. E. Stamen. F. Fruit and fruiting pedicel. Drawn by Al- Shehbaz from holotype (MO-2791311).

FIGURE 6. Heliophila goldblattii. Flower (Photo by Pavel Trávníček and Zuzana Chumová).

FIGURE 7. Heliophila magaliesbergensis. A. Plant. B. Portion of stem and decurrent leaf base. C. Cauline leaf. D. Sepal. E. Petal. F. Lateral stamen. G. Fruit and fruiting pedicel. Drawn by Al-Shehbaz from holotype (PRE-0740714).