Ceropegia laevis (J.R.I. Wood) Bruyns, S. African J. Bot. 112: 424 (2017)

Alharbi, Samah A. & Al-Qthanin, Rahmah N., 2021, Taxonomic revision of Ceropegia sect. Huernia (Asclepiadoideae, Apocynaceae) in Saudi Arabia with three new combinations, PhytoKeys 174, pp. 47-80 : 47

3. Ceropegia laevis (J.R.I. Wood) Bruyns, S. African J. Bot. 112: 424 (2017) Figs 8 , 9 ; Map 3

Huernia laevis ≡ Huernia laevis J. R. I. Wood, Kew Bull. 39:128 (1984).

Type.

Yemen • J. R. I. Wood 3037 (holotype: K [46740.000]) ; Jebel Marran, Khawlan As Sham; 16°49.2672'N, 43°24.7619'E; alt. 1400 m; 31 Oct 1979.

Description.

Dwarf succulent forming dense clump. Branches non-rhizomatous, up to 80 mm long, erect, decumbent, grey-green mottled with purple or red; tubercles 3-5 mm long, 1 mm broad at base, conical, spreading, laterally flattened and joined towards base into 5 angles along branch, abruptly narrowing into fine spreading slender acuminate tooth. Inflorescences 1-2 per branch, each of 2-5 flowers developing in gradual succession on short peduncle with few narrow filiform bracts; pedicel 15 mm long, spreading and holding flower facing horizontally; flowers with no scent; sepals 15 mm long, 3 mm broad at base, narrowly ovate attenuate. Corolla 32 mm diam., broadly funnel-shaped, margin weakly bulging like an annulus; outside smooth, pale cream with 1 heavy (+ 2-4 lighter) raised longitudinal veins running down each lobe; inside shiny creamy-yellow, marked with shiny irregular broad maroon streaks and scrolls, smooth with few low conical papillae (wart-like) at corolla lobes apices each with minute apical bristle; tube 6 mm long, 10 mm broad at mouth, cupular; lobes 10 mm long, 14 mm broad at base, reflexed, deltoid-acuminate, intermediate lobes 1 mm long. Corona without basal stipe; outer lobes (discrete 5 lobes), 4 mm diam., subquadrate, emarginate to shallowly bifid, spreading on base of tube and fused to it towards base, blackish-maroon; inner lobes 1 mm long, purple with cream at base, adpressed to backs of anthers and shorter than them, dorsiventrally flattened with ascending obtuse conspicuous gibbous at base, tapering to small smooth acute apex.

Distribution in Saudi Arabia.

Jabal Al Qahar, 90 km NE of Baysh , Jazan, SW Saudi Arabia ( Chaudhary 2001) .

General distribution.

Probably endemic to SW Arabian Peninsula, known so far from Saudi Arabia and Yemen ( Chaudhary 2001).

Habitat and ecology.

Growing amongst limestones amongst Juniperus at 1828-2000 m alt. ( Collenette 1999). Flowering: mainly September-May

Preliminary conservation status.

Ceropegia laevis should be considered as Nationally Endangered ( EN), according to the IUCN Red List criteria. The species is known from only one location, its EOO and AOO (104.00 km2) would both qualify as Endangered. Its habitat is not part of any protected area and its continuing decline is projected because of anthropogenic activities in the area.

Diagnosis.

Ceropegia laevis can easily be distinguished from most other species of sect. Huernia Huernia in Saudi Arabia by the glabrous shiny yellow background colour of the inside of the corolla, which has an annulus-like area around the mouth of the tube.

Etymology.

Laevis (Latin) smooth, flat; for the glabrous corolla ( Eggli and Newton 2004).

Specimens examined.

Saudi Arabia - Jazan • I. S. Collenette 8180 ( K [fl in spirit: 57656.000]) ; Jabal Qahar; 17°42.0367'N, 42°51.1983'E; alt. 2000 m; 20 Apr 1992.

Figures

Map 3. Distribution of Ceropegia laevis in Saudi Arabia.

Figure 8. Ceropegia laevis, Jabal Qahar, 90 km NE of Baysh, Jazan, Saudi Arabia A Collenette 8177 B ex S Collenette 8180 sub DP 8296. Reproduced from Plowes (2014).

Figure 9. Ceropegia laevis A branch B side view of dissected flower C face view of gynostegium D side view of gynostegium E papillae inside corolla in lobe tip F pollinarium. Drawn from Collenette 8180, Jabal Qahar.