5. Pothos kerrii
Buchet ex P.C. Boyce, sp. nov.
[P. kerrii Buchet
apud Gagnep. in Lecomte, Fl. Gén. lIndo-Chine 6 (1942)
1085, nom. invalid., sine descr. Latin.; P.H. HÈ, Cây-cÀ
Miê__ Nam Vi_t-nam [Fl. South Vietnam in Vietnamese]
(1960) 690, pl.267, G (Pothos scandens sic.); H. Li
in C.Y. Wu & H. Li, Fl. Reip. Pop. Sinicae 13(2) (1979) 19,
pl.3, 8; J. Zhong, Ill. Limestone Mount. Pl. Guangxi (1982) 291;
P.H. HÈ, CâaycÀ Vi_tnam [Ill. Fl. Vietnam
in Vietnamese & English], 3(1) (1993) 421, pl.8256] [P. guangxiensis
H. Li, nom. nud. in sched. KUN]
Pothos kerrii pedunculo stipiteque
longo pergracili, spadice fertili globoso parvulo egregius est in
genere; P. pilulifero nuper descripto leviter similis, sed
pedunculo aliquantum longiore (fere in P. pilulifero absenti),
stipiteque longiore pergraciliore distinguiter Typus: Lao
P.D.R., Tau-yeng (Tawieng), 5 April 1932, Kerr 20900 (fl.) (P! holo;
BK!, K! iso).
Medium-sized slender homeophyllous root-climbing liane to 4 m. Eocaul
not observed; stem of juvenile shoot to 2 mm diam., weakly angled
or terete in cross section, leaves congested; stem of mature sterile
shoot to 6 mm diam., terete in cross section, at first somewhat
densely clothed with leaves, stems eventually becoming naked, naked
portions with prominent nodes to 50 mm distant, stem mid-green;
fertile shoot often branching to three or more orders, stem to 3
mm diam., terete in cross section, mostly densely clothed with leaves,
older portions naked at the base, naked portions with nodes to 30
mm distant; foraging shoot to 2 mm diam., proximally with a few
oblong cataphylls and reduced foliage-leaves at first but soon becoming
naked with slightly prominent nodes to 100 mm distant. Leaves when
fresh mid-green, air drying dull green to brownish; petiole 10
30 ( 50) x 5 10 mm, broadly winged, oblong to oblong-triangular,
, with 2 4 secondary veins per side, veins prominent, especially
in dried material, base decurrent to clawed, apex truncate to auriculate;
lamina 75 130 x 12.5 25 mm, lanceolate to slender-elliptic,
with 2 3 intramarginal veins per side, these arising from
the base and immediately diverging and reaching the leaf tip, base
rounded, apex long-attenuate-mucronate to acute, minutely tubulate.
Flowering shoot much abbreviated, arising from the middle to distal
leaf axils of fertile shoots, bearing a minute prophyll and a few
3 10 mm, sequentially longer cataphylls. Inflorescence solitary;
peduncle 25 40 x 0.5 1 mm, deep purple, very long
and slender, erect to spreading, curving to bring inflorescence
upright,; spathe ovate, 4 6 x 3.5 7 mm, deeply concave
to almost flat, margins straight, base prominently cordate, clasping
and minutely decurrent on the peduncle, apex obtuse with a small
but prominent mucro, greenish purple; spadix stipitate; stipe 10
18 x 0.23 0.75 mm, terete in cross section, erect,
straight, deep purple; fertile portion 3.5 4 x 3.5
4.5 mm, globose, pale yellow. Flowers c. 1 2 mm diam.; tepals
1 x 0.3 mm, oblong-cymbiform, pale yellow, apex fornicate, triangular,
truncate; stamens 1 3 x c. 0.35 mm, filaments strap-shaped,
thecae c. 0.2 mm diam., yellow; ovary 1 1.5 x 0.25
0.75 mm, compressed angular-ellipsoid, yellow-green to dirty white;
stylar region truncate; stigma punctiform. Infructescence with 1
7 berries; fruit 10 15 x 7.5 10 mm, obclavate
to ellipsoid. Seeds c. 3 6 mm diam., ellipsoid to compressed-globose.
Distribution China (Guangxi), Lao P.D.R., Vietnam.
Habitat & Ecology Seasonal rather dry evergreen
hill forest forest on precipitous granite slopes. 400 550
m.
Notes Pothos kerrii is distinctive by the
short petioles and long, narrow leaf lamina with prominently raised
veins and by the graceful inflorescences with a very long, almost
filamentous peduncle, a long slender stipe and small spherical fertile
spadix. Confusion can occur with P. kerrii in Vietnam and
China where P. pilulifer
is superficially similar. Pothos
pilulifer differs in having
broader leaves and an inflorescence with a very short, stout pedicel,
a stout, straight stipe and a larger fertile spadix.
Rather few collections of P. kerrii exist, although this
may be an artefact of collecting rather than a reflection of natural
rarity considering the widespread provenance of the known collections.
During fieldwork in 1997 at Bach Ma, Quang Nam Da Nang province,
Vietnam, P. kerrii was a ubiquitous element of the forest
liane flora (Boyce & Dzu, pers. obs.) but seldom flowering.
Geographically representative selection of collections studied:
CHINA. Guangxi: Ninming County, 11 Oct. 1979, Longgan Exped. 11605
(fl.) (KUN).
LAO P.D.R. Louangphrabang: Louangphrabang, 019° 52N, 102°
08E, April 1913, dAlleizeite s.n. (fl.) (L). Xieng Khouang:
Tau-yeng (Tawieng), 5 April 1932, Kerr 20900 (fl.) (type of Pothos
kerrii, P holo; BK, K iso).
VIETNAM. Hoa Binh: Muong Khen, 020° 40N, 105° 20E,
April 1933, Petelot 4691 (fl.) (P). Lang Son: Hui Lui, 2 Oct. 1996,
Nguyen Van Dzu 104 (fl.) (HN). Quang Nam Da Nang: Go Oi,
22 Feb. 1941, Poilane 31452 (fl.) (AAU, K, L, P). Yen Bai. Dong
Tam, 021° 30N, 105° 00E, 5 May 1961, Soviet-Vietnam
Expedition 1806 (fl, fr.) (LE).
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