13. Pothos lorispathus
Pothos lorispathus Ridl.,
J. Straits Br. Roy. Asiat. Soc. 86 (1922) 310 (as lorispatha).
Type: Malaysia, Selangor, Batu Caves, Ridley s.n. (fl.) (SING!
holo; K! iso).
Moderate, robust heterophyllous (?) root-climbing liane to 8 m. Eocaul
& juvenile shoot not observed; stem of mature sterile shoot to
6 mm diam., terete in crosse section, stem dark, glossy green, becoming
brown with age, moderately clothed with leaves, eventually becoming
naked, naked portions with somewhat prominent, 50 100 mm distant
nodes, often producing long, free and adherent feeding roots, these
terete with a slightly rough, occasionally minutely spiny, epidermis;
fertile shoots seldom branching, stem of fertile shoot to 4 mm diam.,
densely clothed with leaves; foraging shoot subterete in cross section,
to 1 mm diam., proximally with a few oblong cataphylls and reduced
foliage-leaves but soon becoming naked with slightly prominent nodes
to 100 mm distant. Leaves when fresh mid-green adaxially, slightly
paler abaxially, stiffly but thinly chartaceous, air drying dull greenish;
petiole 30 70 mm long, slender, sheath somewhat prominent,
extending to just below geniculum, basally clasping, apically briefly
auriculate to slightly ligulate; lamina 100 340 x 25
100 mm, oblong-elliptic, often falcate, unequal, occasionally quite
strongly so, with 2 intramarginal veins per side, the lowermost arising
from the base, the next arising from the lowest part of the midrib,
outer intramarginal vein remaining very close and parallel to margin,
inner vein c.10 mm distant, both reaching the leaf tip, base rounded,
apex acute to acuminate, very briefly tubulate. Flowering shoot abbreviated,
usually leafless but with 1 several well-developed cataphylls,
very occasionally with one or more fully developed but reduced leaves,
arising from below the leaf axils of fertile shoots. Inflorescence
solitary but flowering shoots almost always reiterating and thus several
inflorescences at varying degrees of developmental maturity often
present; peduncle 27 50 x 2 3 mm, moderately stout,
erect or curving and ultimately ascending and the inflorescence held
erect, dull green; spathe 25 100 x 5 15 mm, lorate,
spreading, base auriculate, auricle margins inrolled, barely decurrent
on the peduncle, apex obtuse, acuminate, mid-green; spadix stipitate;
stipe 8 15 x c. 2 mm, slender, terete, lime green; fertile
portion 50 65 x 3 4 mm, cylindrical to tapering slendercylindrical,
straight to slightly curved, base unequal, slightly cochleate, creamy-yellow.
Flowers c. 1.5 mm diam.; tepals 1 x 0.3 mm, oblong-cymbiform, pale
yellow, apex slightly fornicate, triangular, truncate, margins minutely
reflexed; stamens 1 4 x c. 0.5 mm, filaments strap-shaped,
thecae c. 0.2 mm diam, pale yellow; ovary 1 1.5 x 0.25
0.75 mm, compressed globose, yellow-green; stylar region rounded;
stigma punctiform. Infructescence with numerous berries; fruit 10
15 x 5 8 mm, obclavate to ellipsoid, ripening deep scarlet,
with basal chartaceous tepal remains, stigmatic remnant tiny, on a
flattened stylar region. Seeds c. 4 6 x 2 4 mm, ellipsoid.
Distribution Peninsular Malaysia, Thailand. Specimens
from Sabah and Sarawak may be referable to P. lorispathus
or may represent an undescribed species.
Habitat & Ecology Damp to rather dry evergreen hill
forest on limestone and granite. 50 100 m.
Notes In the review area P. lorispathus
is known only from Yala province, Thailand, where it occurs on limestone
and granite. Originally described from the Batu Caves, Selangor, Malaysia,
P. lorispathus it has seldom been recollected and is
known from very few specimens.
Although strerile specimens are very difficult to distinguish, fertile
specimens are instantly recognizeable by the size and colour of the
inflorescences; there are no other large green-inflorescenced Pothos
in the review area. Pothos lorispathus is superficially similar
to P. lancifolius but
readily distinguishable by the lorate spathe, stipitate spadix and
slender (not thickened) peduncle.
Geographically representative selection of collections studied:
THAILAND. PEN75. Yala: Bang Lang N.P, 006° 12N, 101°
10E, 30 March 1997, Boyce 1218 (fl, fr.) (BKF, K and K Spirit
Coll. no. 63296).