New Ceropegia from Laos 
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10(—12) x 0.5-1.2 cm, slightly fleshy but flexible, base attenuate, apex acute, pale 
green above, paler underneath, sparsely pubescent above, underneath pubescent along 
main vein only, trichomes curved, 100-200 pm long, older leaves glabrous; venation 
pinnate, lateral veins obscure; colleters 1 or 2 at base of lamina, globose, 200-300 
pm in diameter. Inflorescences 1-2 flowered, with only one flower open at a time, 
peduncles extra-axillary, one per node, 0.5-2 x 1.5-2 mm in diameter, reddish green, 
glabrous; pedicels erect, 8—15(—25 when fruiting) x c. 1.5 mm in diameter, reddish 
green to whitish, glabrous or very sparsely pubescent; bracts 1 or 2 at base of pedicel, 
lanceolate, 1-2 mm long, reddish, apex acute. Calyx lobes narrowly lanceolate, 4-5 
x 0.7-1 mm, glabrous, apex acuminate, reddish, glabrous; with one colleter at each 
sinus, conical, 400-500 x 150-200 pm, acute. Corolla 35—45 mm in total length, tube 
upright, straight or slightly curved, glabrous, with a bulbous base, a cylindrical mid 
portion and funnel shaped apex; tube (20-)23-27 mm long, base 5-7 mm in diameter, 
cylindrical part 2.5-3.5 mm in diameter; base white and densely spotted red outside, 
inside white and striped red; cylindrical part red with paler dots outside, dark red and 
striped maroon inside; apex red and spotted green outside, cream and striped green 
inside; corolla lobes broadly ovate, folded, (12-) 15-17 x 7-8.5 mm, basal part cream- 
yellow, ciliate, apex acute, connate at tips, green and pubescent and ciliate inside, 
maroon red and glabrous outside. Gynostegium stipitate, stipe 0.4-1.6 x 0.9-1.1 mm 
in diameter, white, glabrous. Gynostegial corona of staminal and interstaminal parts, 
interstaminal lobes joined to form a shallow cup, 4.5-5 mm in diameter, purple with 
a white base; free lobes deeply bifid with the tips of adjacent lobules touching each 
other, ascending-erect, small triangular, c. 1.5 x 1 mm, maroon red, inside pilose 
with spreading translucent-white trichomes c. 0.5 mm long, staminal corona lobes 
connivent-erect, linear, terete, 1—1.2 x 0.25-0.35 mm, pinkish white. Pollinaria: 
pollinium broadly ovoid, yellow, 350^100 x 350^100 pm, caudicles c. 200 pm long, 
corpusculum clavate, reddish brown, 250-300 x 90-110 pm. Ovary narrowly conical, 
2.1-2.3 x 0.5-0.7 mm wide at the base, apex truncate, glabrous. Mericarps held erect, 
linear, slightly curved, c. 11.5 x 3 mm (immature), reddish green. Seeds not seen. 
Distribution. Laos, Champasak Province, in the vicinity of Ban Hnongluang Wat. 
Habitat and ecology. Ceropegia laotica is a perennial tuberous herb found in a single 
population where all individuals were rooted in very thin soils (3-6 cm thick) over 
large sandstone boulders partially exposed. The plants were growing among grasses 
and climbing over gingers, bamboo and Ficus spp. at the edge between open grassland 
vegetation and short stunted forest (Fig. 3). 
Provisional IUCN conservation assessment. Endangered EN Blab(iii) + B2ab(iii) 
using the guildelines from the IUCN Standards and Petitions Subcommittee (2017). 
Ceropegia laotica is known only from the type locality. A thorough survey of the 
Bolaven Plateau is lacking and we have little information on similar habitats in 
neighbouring Thailand and Vietnam for a conclusive conservation assessment. 
If, however, we estimate the EOO as the entire Bolaven Plateau (< 5000 km 2 ) and 
