Fig. 1. Hoya
narcissiflora. A. Flower from above. B. Corolla with corona removed. C.
Corolla and calyx, from underneath. D. Flower, side view. E, F. Corona, side
view. G. Corona, from underneath. H. Corona, from above. I. Calyx and ovaries.
J. Pollinarium.
Hoya
narcissiflora S. Rahayu & Rodda spec. nov. Figs.
1 3. — Type: Indonesia, West Kalimantan, Sanggau, 100–300 m, on a slope close
to a stream, primary forest “Hutan Adat”, Feb 2014 (cultivated at Bogor Botanic
Gardens from vegetative material collected in the wild by Mr. Maskuran) Sri
Rahayu JQ705 (Holotype BO, isotype KRB).
Diagnosis.
Similar
to H. danumensis as both taxa have elliptic to oblong thin laminas and
ovoid corona lobes. It can be separated from H. danumensis on the
shape of the corona lobes that
are less than 1.5 times as long as broad in H. narcissiflora vs. ca. twice
as long as broad in H. danumensis.
 |
| Fig. 2. Hoya narcissiflora. Inflorescence from a plant in cultivation. A. From above. B. From underneath. (Photos:Maskuran) |
Description.
Epiphytic climber, shrubby when young, with white latex in all vegetative
parts, glabrous. Stems slender, lignified when old, internodes very
variable in length, 0.5 – 10 cm long, 2.0 – 2.5 mm in diameter, green when
young, grey-green when mature; Leaves petiolate; petiole, 0.5– 1.0 cm ×
1.5 – 2.0 mm in diameter, channelled above, light green; lamina elliptic to
oblong, thin, 5 – 12 × 2 – 4 cm, base cuneate without colleters, apex acute or
acuminate, discolorous with upper side fresh to dark green, lower side paler
green, young leaves pale green, venation pinnate, secondary veins 4 – 5 pairs. Inflorescence
pseudoumbellate, convex, 5 – 10 flowered; peduncle ageotropic, with a rachis
turning positively geotropic, very short 4 – 6 × 1.5 – 2.0 mm in diameter, grey
green, glabrous. Flowers weakly scented, produce visible nectar from the
second day onwards, lasting 4 – 5 days in cultivation; pedicel positively
geotropic, ca. 2.5 cm × ca. 1 mm in diameter, white-pale green,
glabrous. Calyx lobes free, ovate to triangular with a round tip, 1.0 –
1.2 × 0.8 – 1.0 mm wide, creamy white or light green, glabrous, basal
colleters one in each calyx lobe sinus, triangular, 2.3 – 2.7 × 1.5 – 1.7
mm. Corolla very shallowly campanulate, almost round in outline,
flattened and slightly campanulate at the centre underneath the corona when in
full bloom, white or very pale yellow; tube 10–14 mm in diameter, undulating and
with a depression underneath each corona lobe, visible as a small hump on the
outside in between the calyx lobes, glabrous outside, pubescent inside only
underneath the corona; lobes broadly triangular, 6 – 9 × 3.5 – 5 mm, folded in
the centre, apex acute, glabrous. Corona staminal, erect, 6 – 7 mm in
diameter, 5.0 – 5.5 mm high, white or yellowish white; lobes upright,
when observed from above round to ovoid, 2.2 – 2.5 × 1.0 – 1.2 mm, 5.0 – 5.5 mm
tall, outer process concave with an acute tip, inner process apiculate; skirt
located at the base of each coronal lobe, 1/3 of the corona length, thin,
rhomboid with short acuminate apex at the centre, white or yellowish white; Anthers
with apical round membranaceous appendage just exceeding
the style-head apex. Pollinia elliptic oblong, 500 – 550 × 100 – 150 μm,
narrowing towards
the base, apex round, sterile edge prominent along the outer edge of the
pollinium; corpusculum elliptic, 50 – 60 × 25 – 30 μm with an acute tip,
caudicle almost rectangular, 90 – 100 × 20 –25 μm, twisted at the base;
concave, hyaline. Style -head 5 angled in cross section,
style-head apex acute, 0.5 – 0.6 mm high, 1.4 – 1.5 mm broad at the base. Ovaries
elliptic with narrower tip from the base, ca. 1.9 – 2 mm × ca. 0.7
mm at the widest area in the centre, light green, glabrous. Fruit and seed
not seen.
IUCN
conservation assessment. This species is only known from a
single locality in West Kalimantan. The preliminary conservation status of H.narcissiflora
is therefore Data Deficient (DD, IUCN 2014). Ex situ collections are
present in Bogor Botanic Gardens (from type locality) and several private
collectors in Indonesia as Mr. Maskuran has been distributing cuttings from his
original collection among the Hoya growers under the community Hoya Indonesia.
Source: Sri Rahayu and M. Rodda