124 
Card. Bull. Singapore 69(1) 2017 
positively geotropic, pseudo-umbellate, consisting of 1-5 flowers; peduncle terete, 
1-3 cm x c. 1 mm, older peduncles forming a rachis from previous flowerings, new 
peduncles hirsute, old peduncles often almost glabrous; pedicels terete, 2-3 cm x c. 
1 mm in diameter, light green, often spotted in purple near calyx, glabrous (sparsely 
pubescent). Flower buds apically flattened, creamy white with pink and purple dots. 
Calyx c. 5 mm in diameter, calyx lobes ovate-lanceolate, c. 2 x 1.5 mm, apex acute 
and ciliate. Corolla broadly campanulate, almost rotate, fleshy, 4-5 cm in diameter, 
cream-white coloured with a slightly greenish-yellow translucent hue, outside often 
pink-maroon if exposed to bright light; tube 1.2-1.5 cm long, glabrous to puberulous 
within, glabrous near centre, outside glabrous; lobes broadly triangular with upturned 
auricles at the sinuses, c. 1.5 x 1.5 cm, margins entire and slightly revolute, apex acute, 
inside sparsely pubescent, outside glabrous. Corona staminal, c. 6 mm high, c. 14 mm 
in diameter, fleshy, cream-white; lobes broadly elliptic, c. 6 x 4.5 mm, inner processes 
much reduced and linear, 0.8 x 0.3 mm, each outer process with a sharp central ridge 
and a basal longitudinal protrusion on each side running from the base of the guide 
rails up to the apex, with basal revolute margins right up to the apex, not basally fused 
with filament tube. Style-head basal convex process narrowed into a raised convex 
tip, much exposed and not hidden by anther appendages, light green. Pollinia elliptic, 
900-950 x 400-500 pm, without sterile edge, corpusculum ovate, 500-600 x 400- 
450 pm, caudicles attached at lower half of corpusculum, 300-350 x 130-150 pm. 
Ovary conical, c. 3 mm long, narrowing at 2 mm from the base; each carpel c. 1.5 mm 
wide at base, light green, glabrous. Fruit and seed not observed. 
Distribution. Only found in the Mebu area, Madang Province at 1300 m altitude, 
where 12 specimens were sighted at only one site near a deep, moist montane valley. It 
has never been recorded outside that locality, even in other parts of the same mountain 
range. 
Etymology. Named after Constantinus Lindfors in Sweden, a supporter of the first 
author’s work in PNG. 
Habitat and ecology. Hoya juhoneweana subsp. lindforsiana inhabits mossy riverine 
primary forests where it grows on large mature trees but is absent in the adjacent 
mature but drier secondary forests and in the subsistence gardens. The co-occuring 
taxa Hoya oreostemma Schltr. and Hoya solaniflora are more abundant and grow well 
on younger trees along paths and in mature secondary forest with more sunlight. The 
inability to recolonise secondary habitats has also been observed for the two similar 
taxa H. juhoneweana subsp. juhoneweana and H. urnijiora. 
Provisional IUCN conservation assessment. Critically Endangered CR B2a,b(iii), D 
(IUCN, 2016). Despite extensive field expeditions in the Finisterre-Sarawaged Range 
by the first author and many other botanists (Vollering et al., 2016) this subspecies has 
only been recorded at the type locality, where a single population including only 12 
individuals was seen in an area of < 1 km 2 . 
