Cyphia deliae H.M.Steyn, 2024

Steyn, Hester M. & Van Wyk, Abraham E., 2024, Cyphia deliae (Campanulaceae: Cyphioideae), a new species from South Africa and Eswatini, Phytotaxa 633 (3), pp. 265-274 : 266-270

Cyphia deliae H.M.Steyn , sp. nov. (Figs 1–3)

Diagnosis:— Cyphia deliae differs from C. bolusii , its morphologically most similar relative, in having bigger flowers, petals ca. 6.5–7.6 mm long (vs. 4.0–5.0 mm long), a scape with cauline leaves decreasing in size upwards (vs. scape leafless), bracts, bracteoles and calyx lobes with 2 or 3 pairs of small teeth along the margin (vs. usually with entire margins), and flower buds with an acute tip (vs. buds with a rounded tip).

Type:— SOUTH AFRICA. Mpumalanga: Barberton [Ehlanzeni] District. Olifantskop, Tinie Louw Nature Reserve , 1656 m, (2531CC), 28 January 2022, Steyn 2759 (holotype PRE!; isotype J!)

Erect herb, ca. (20–)25–35(–45) cm tall, usually unbranched. Stem terete, striate, leafy towards base, with watery latex. Leaves sessile, shortly decurrent, usually lanceolate or ovate, occasionally obovate; radical and basal leaves (20–)30–40 × (6–)8–10(–20) mm, glabrous, puberulous to pubescent, often glabrous on abaxial surface, apex obtuse to acute, base attenuate, margin appears crenate due to small, appressed serrations, usually revolute, abaxial surface usually with prominent veins; cauline leaves present, decreasing in size apically, grading into bracts. Inflorescence a lax spike; scape with widely spaced cauline leaves (“sterile bracts”), scape and rachis pubescent. Flowers sessile, buds with acute tip, usually solitary, 8.5–11.0 mm long. Bracts lanceolate, (4.8–)5.0–6.8(–7.5) × 0.9–1.2 mm, margin with 2 or 3 pairs of small teeth towards base, puberulous to pubescent; bracteoles lanceolate, 3.0–5.5(–5.8) × 0.6–1.0 mm, usually with 1(2) pair(s) of teeth towards base, puberulous to pubescent. Calyx tube 1.6–2.0 mm long (accrescent in fruit); lobes narrowly lanceolate, erect, (4.0–) 4.2–5.7 mm long, with (1)2 or 3 pairs of teeth spaced along margin, puberulous to pubescent. Corolla narrowly ovoid, rarely urn-shaped, with petals recurved at tip, mainly white to pinkish on inside, often light orange on outside, segments strap-shaped, gradually tapering towards tip, 6.5–7.6 × 1.0– 1.2 mm, subglabrous to puberulent on outside, villose on inside with tip of petal curved outwards and glabrous within. Stamens shorter than half of corolla length, 3.0– 3.2 mm long; anthers 1.6–1.8 mm long, some anthers hairy on back, others glabrous. Style 1 mm long, stigma oblique ( Figs 2 & 3 ). Fruit only known from very young developing stage ( Fig. 2F ); mature fruit not seen.

FIGURE 1. Known distribution of C. deliae (•) based on specimens in Herbs. BNRH, J, LYD, PRE, and NU; and C. bolusii (▲) based on specimens in BODATSA, as well as observations on iNaturalist.

Phenology: —Flowers have been recorded mainly in January and February (summer).

Distribution and habitat: —All currently known herbarium specimens of C. deliae were collected in the Barberton area of Mpumalanga, South Africa, and the adjacent Pigg’s Peak area in Eswatini. This distribution range falls within the Barberton Centre of Endemism ( Van Wyk & Smith 2001). Plants are found on rocky outcrops on moderate to steep mountain slopes ( Fig. 4 ) at elevations between 1500 and 1670 m. They grow in sandy to sandy loam soils in Barberton Montane Grassland ( Mucina & Rutherford 2006). It is difficult to determine whether some of the older specimens, which have less precise locality information, were collected on serpentine-derived soils. However, the type specimen (Steyn 2759) and at least three other gatherings were collected from populations growing on quartzitederived sands (Venter 9177) and other non-serpentine soils (D. Oosthuizen, pers. comm.). This is unlike C. bolusii , which is considered a serpentine endemic.

Conservation status: — Cyphia deliae is only known from six locations and has a restricted range (EOO <157 km 2). Based on its narrow range and the potential threats of habitat degradation due to mining, commercial afforestation, fire suppression, and invasive alien plant species, C. deliae qualifies for Vulnerable B1ab(iii); C2a(i) ( IUCN 2012). The Barberton Montane Grassland is classified as Vulnerable, with only approximately 26% of this vegetation type protected within conservation areas, such as Mountainlands Nature Reserve and Songimvelo Game Reserve. Nearly 40% of the area has been transformed by commercial timber plantations ( Mucina & Rutherford 2006).

Eponomy: —The new species is named for Mrs Delia Oosthuizen (née Beukes) (20 July 1969 –) from Mountainlands Nature Reserve, Barberton; a keen amateur botanist, photographer, plant collector, and member of the Mpumalanga Plant Specialist Group.

Notes: —The new species can be confused with C. bolusii ( Fig. 5 ), a species from which it differs in certain inflorescence and flower characters ( Table 1), as well as the peak flowering time. Known distributions of these species do overlap.

Both C. bolusii and C. deliae were not included in recent molecular analyses of Cyphia , but it is expected that these species will fall in the C. elata clade (E.B. Knox, pers. comm.), an unresolved clade of erect species with subsessile to sessile flowers, occurring in eastern South Africa and Eswatini.

Additional specimens examined (paratypes): — SOUTH AFRICA. Mpumalanga: Barberton District, ca. 10 km SW of Barberton, Farm Ameide 737, ± 2 km SW of Shokhohlwa Peak, 1496 m, (2530DD), 25 Jan. 2015, Bester 12470 ( PRE!) ; Mountainlands Reserve, Twello gate, (2531CC), 13 Jan. 2013, Burrows & Turpin 13282 (BNRH!, NU!) ; Kangwane, Songimvelo Game Reserve, Farm Schoonoord , Makhonjwa Hills , (2531CC), 9 Dec. 1992, Dreyer 278 ( PRE!) ; Barberton District, farm Mendon 379 JU, SW slope of “Maid-of-the-Mist”, (2531CC), 10 Jan. 2015, Ngozo, Turpin & Sekulane 6 (BNRH!, PRE!) ; Barberton District, Ameide 717JT, ridge to N. of track of R40, 1652 m, (2531CC), 27 Jan. 2022, Steyn 2756 ( PRE!) ; Tinie Louw Natuurreservaat , 5458 ft [1660 m], (2531CC), 15 Jan. 1983, Venter 9177 ( LYD!) .

— ESWATINI. Pigg’s Peak, Emlembe, (2531CC), 1 Feb. 1959, Compton 28504 (PRE!).

Figures

FIGURE 2. Cyphia deliae. A. Habit. B. Leaves. C & D. Flowers, showing flower buds with acute tips and calyx lobes with teeth along the margin. E. Flower with calyx and petals removed (note hairs on back of anthers). F. Young fruit. Photographs by W. McCleland (A), D. Oosthuizen (B–E), H. Steyn (F).

FIGURE 3. A comparison of the flower morphology in Cyphia deliae (A, C, & E) and C. bolusii (B, D & F), as seen in dried herbarium material. A. Flower bud, showing acute tip. B. Flower bud, showing rounded tip. C. Flower in side view; note villose petals. D. Flower in side view; note pubescent petals. E. Flower with petals removed; note sparsely hairy back of anthers. F. Flower; note densely hairy back of anthers. Photographs by H. Steyn.

FIGURE 4. Habitat of Cyphia deliae, with the town of Barberton in the distance. Photograph by D. Oosthuizen.

FIGURE 5. Cyphia bolusii. A. Habit. B. Leaves. C & D. Flowers, showing buds with rounded tips and calyx lobes with entire margins. Photographs by K. Braun.