Epipremnum pinnatum 'Aureum'
Epipremnum pinnatum (L.) Engl. 'Aureum'
(see Nicolson, Allertonia 1 (1978) 347.) -- Pothos aureus Linden
& André, Ill. Hort. 27 (1880) 69. -- Scindapsus aureus
(Linden & André) Engl. in Engl., Pflanzenr. 37 (IV.23B)
(1908) 80. -- Rhaphidophora aurea (Linden & André)
Birdsey, Baileya 10 (1963, 1962) 159 -- [Rhaphidophora
aurea (Linden & André) Furtado, Gard. Bull. Singapore
20 (1964) 379, comb. superfl.] Epipemnum aureum (Linden &
André) G.S. Bunting, Ann. Missouri Bot. Gard. 50 (1964, 1963)
28. -- Type: Ill. Hort. 27 (1880) pl. 381. Epipremnum mooreense
Nadeaud, J. de Botanique 13 (1899): 6. Type: ****, Nadeaud s.n.
NOTE: This information is somewhat outdated. Please refer to Aroideana V.27 p.205 A Review of Epipremnum (Araceae) in Cultivation by Peter Boyce for more recent information, partially excerpted here:
EPIPREMNUM AUREUM VS.
There exists a suite of vegetative characters
that consistently separate E. pinnatum
and E. aureum. In young pre-adult
plants the leaf laminae are different in
shape and texture. Those of E. aureum are
ovate to ovate-lanceolate and thicker in
texture than the lanceolate to elliptic preadult
leaves typical of E. pinnatum. As
plants progress through the pre-adult
stage and approach maturity more differences
become apparent. The distinctive
netted sheath-remains, present in E. pinnatum,
are absent in E. aureum while the
leaf lamina 'pin-holes' characteristic of E.
pinnatum are far fewer in number, do not
develop to any degree and hardly ever
perforate, while leaf division by means of
pinnation is sporadic and occurs only as
solitary to few irregular rather shallow pinnations.
Leaf texture remains consistently
thicker than for E. pinnatum and leaf lamina
shape remains more or less constant,
the lamina simply increasing in size and
not perceptibly altering shape. Massive flagellate
foraging shoots develop, often in
some quantity, and a profusion of prominently
lenticellate robust feeding roots is
produced, many of which remain hanging
free and reach the ground. Overall the
plants are considerably more robust and
produce many climbing stems (E. pinnatum
is generally noticeably less robust and
Most literature emphasises the shy-flowering
nature of E. aureum. Enquiries at
Bogor confirmed that the numerous plants
cultivated there of both the variegated and
the wholly green plants of E. aureum are
shy flowering. This is in marked contrast
to E. pinnatum, which flowers profusely
wherever it occurs in the wild and in cultivation.
Very large root-climber to 16 m. Pre-adult plant usually forming
modest terrestrial colonies. Adult plant with stem 5--40 mm diam.,
internodes 2--30 cm long, separated by prominent leaf scars, with
prominent irregular whitish longitudinal crests, older stems with
distinctive matt to sub-lustrous orange-brown papery epidermis growing
stems mid-green to pale yellow-green, occasionally with obscure
large dull yellow to white variegations. Flagellate foraging shoots
common, these arising high in the canopy and reaching the ground.
Aerial roots of two types, clasping roots densely arising from nodes
and internodes, feeding roots prolific, both strongly adherent to
substrate and free, both root types pubescent, mid- to dark brown,
growing tip pale brown-yellow, feeding roots later prominently lenticellate.
Cataphylls and prophylls soon drying and then degrading to netted
sheaths, these sparsely clothing upper stem and mostly soon falling.
Foliage leaves scattered on lower stem, becoming clustered distally.
Petiole 19.5--50 cm x 3--15 mm, canaliculate, smooth, mid-green
to rather bright yellow-green, air-drying mid- to dark brown; apical
geniculum 16--50 x 3--8 mm, smooth, basal geniculum 3--7 x 1--1.5
cm, both genicula barely on not greater in diameter than petiole;
petiolar sheath extending to up to mid-way along apical geniculum,
at first sub-membranaceous, soon drying chartaceous and degrading
to untidy, slightly netted weak fibres, then falling to leave a
smooth, mid-brown scar. Lamina 10--93 x 5--60 cm, entire to irregularly
pinnatifid, ovate to elliptic in outline, sub-coriaceous, apex acute
to acuminate, base moderately cordate, divisions pinnatifid to pinnatipartite;
pinnae up to half the length of the lamina wide, apex truncate;
terminal pinna, if present, smooth-margined, some leaves with few
minute pellucid dots adjacent to the midrib in leaves, pellucid
dots rarely perforating and almost never enlarging, lamina dull
to somewhat glossy mid-green; slightly paler beneath, usually irregularly
yellow or white variegated, rarely entirely mid-green; pinnae each
with 1 (very rarely more except for the terminal pinna) compound
primary lateral vein and several to rather many interprimary veins,
these diverging from midrib at c. 70°, individual elements of
the compound vein diverging at c. 10° from various points along
the pinna, the vein thus becoming finer towards the margin; interprimary
and secondary venation mostly remaining sub-parallel to compound
primary vein, some weaker elements further dividing and becoming
sub-reticulate, all other higher order venation conspicuously reticulate,
midrib impressed above, very prominently raised beneath, lower order
venation slightly impressed to almost flush above, variously raised
beneath, higher order venation flush above, flush or nearly so beneath
in fresh material but raised and rather conspicuous in dried specimens.
Inflorescences several together, first inflorescence subtended by
a usually fully developed foliage leaf and a swiftly disintegrating
cataphyll, at anthesis partially to almost completely exposed. Peduncle
c. 6 cm x 10--15 mm, stout, terete, pale green to yellow-green.
Spathe canoe-shaped, shortly acuminate, spreading wide at anthesis
and margins reflexing, c. 15 cm x 6--7 cm when pressed flat, exterior
green, later whitish, interior whitish, air-drying dark brown. Spadix
17--19 x 2--3 cm, sessile, cylindrical, bluntly tapering towards
the apex, base slightly obliquely inserted, whitish, air-drying
almost black. Flowers 3--5 mm diam.; ovary 4--6 x 3--5 mm, cylindrical,
basal part slightly compressed; ovules 2 ; stylar region 3--5 x
2.5--5.5 mm, trapezoid, rather robust, apex flattened, margins somewhat
raised in dry material; stigma linear, 2--6 x 0.1--0.5 mm, longitudinal;
stamens 4; filaments c. 6 x 0.5 mm; anthers narrowly ellipsoid,
c. 1.5 x 0.75--1 mm;.
- Unknown in the wild, alleged to have originated in the Solomon
Habitat - Unknown
in the wild. Where it escapes in Malaysia it grows in damp evergreen
forest and abandoned rubber plantations at low altitudes.
Note - 1. Described
from cultivated material alleged to have originated in the Solomon
Islands, E. pinnatum 'Aureum' has a tortuous nomenclatural
history. It was first published as Pothos aureus (Linden & André
1880) based on sterile pre-adult material. The curious choice of
generic placement, given the manifestly different appearance of
the plant to any species of Pothos as then circumscribed, remained
unchallenged until Engler (Engler & Krause, 1908) removed the
species, still unflowered, to Scindapsus. His generic choice was
influenced by the plants overall appearance. There it remained
until Birdsey (1962) reported the first recorded flowerings, in
Puerto Rico and at the Fairchild Tropical Garden, Florida, and thus
for the first time the critical ovule characters that showed the
plant to belong to Epipremnum sensu Engler & Krause (1908).
However, Birdsey chose to follow Bakhuizens (1958) generic
ideas and transferred Pothos aureus to Rhaphidophora
as R. aurea. Furtado (1964), unaware of Birdseys publication,
published the same combination when reporting the flowering of "P.
aurea" in Singapore. Furtado based his generic placement
upon D.H. Nicolsons hand-written annotations to Engler &
Krauses (1908) key (Nicolson then also followed Bakhuizens
generic concepts). Bunting (1964), transferring P. aureus to Epipremnum,
remarked that flowering material is very similar to that of
E. pinnatum, and must be included in that genus.
He went on to reiterate the characters he regardd as distinct for
Epipremnum compared with Rhaphidophora. Nicolsons
(1978) paper discussing E. aureum and E. pinnatum
stated that there were insufficient differences for them to remain
distinct species and concluded by proposing that E. aureum
be regarded as cultivar of E. pinnatum. In the same
paper Nicolson also laid to rest the long-standing nomenclatural
problems associated with the names Epipremnum and Rhaphidophora
that formed the cornerstone of Bakhuizens paper (Bakhuizen,
1958). Nicolsons 1978 generic circumscription and cultivar
status of aureum have since been incorporated into floras
of Fiji and Sri Lanka (Nicolson 1979, 1988) and various checklists
(e.g. Hay et al., 1995).
2. The wild provenance of 'Aureum' is unresolved.
The type description of Pothos aureus states that the original
plant came to Lindens garden from the Solomon Islands, but
this cannot be substantiated. Certainly 'Aureum' appears
never to have been collected in the wild and the possibility exists
that it is a horticultural selection of E. pinnatum.
Such selections, looking radically different to the progenitor,
are common in some plants (Codiaeum, Polyscias, etc.) and when seen
in isolation appear highly distinct. Plant hunters of the nineteenth
century were often on the look out for new horticultural novelties
and it is possible that 'Aureum' was gathered from cultivation
somewhere in the Solomon Islands.
3. There exists a suite of vegetative characters that consistently
separate E. pinnatum
and 'Aureum'. Based on observations made in Zone 1
of the Tropical Conservatory at Kew, at the Forest Research Institute
Malaysia, Kepong and in Bogor Botanic Garden, Java the following
can be stated. Beginning at the earliest observed stage, that of
young pre-adult plants, the leaf laminae are different in shape
and texture. Those of 'Aureum' are ovate to ovate-lanceolate
and thicker in texture than the lanceolate to elliptic pre-adult
leaves typical of E. pinnatum.
As plants progress through the pre-adult stage and approach maturity
more differences become apparent. The distinctive netted sheath-remains
usually present in E. pinnatum
are absent in 'Aureum' while the leaf lamina pin-holes
characteristic of E. pinnatum
are far fewer in number, do not develop to any degree and hardly
ever perforate. Leaf division by means of pinnation is sporadic
and occurs only as solitary to few irregular rather shallow pinnations.
Leaf texture remains consistently thicker than for E.
pinnatum and leaf lamina shape remains more-or-less constant,
the lamina simply increasing in size and not perceptibly altering
shape. Massive flagellate foraging shoots develop, often in some
quantity, and a profusion of prominently lenticellate robust feeding
roots is produced, many of which remain hanging free and reach the
ground. Overall the plants are considerably more robust and produce
many climbing stems (E. pinnatum is generally noticeably
less robust and few-stemmed). The observations made at the Forest
Research Institute Malaysia, Kepong and Bogor Botanic Garden, Java
support those at Kew. All the characters observed at Kew were seen
in large numbers of plants of both E. pinnatum and 'Aureum'
growing in a variety of situations. Most notably, several plants
of 'Aureum' with entirely green leaf laminae were observed
that retained the distinctive overall appearance of the variegated
plants. Furtados comment that the variegated plant reverts
to the typical green plant in shady situations was not supported
by my observations in Bogor where mature variegated plants were
often seen in deep shade and adult green plants could be seen in
full sun. This suggests that the green forms are somatic segregates
from the variegated chimera. Most literature emphasises the shy-flowering
nature of 'Aureum'. Enquiries at Bogor confirmed that both
the variegated and the wholly green plants of 'Aureum' cultivated
there are shy-flowering. This is in marked contrast to E.
pinnatum which flowers profusely wherever it occurs in the
wild and in cultivation.