Pothos
Pothos L., Sp. Pl. ed.1 (1753) 968 & ed.2
(1763) 1373 1374, 1675; Lour., Fl. Cochin. (1790) 532;
Schott in Schott & Endl., Melet. Bot. (1832) 21; Endl., Gen.
Pl., 3 (1837) 239; Kunth, Enum. Pl., 3 (1841) 65 66; Schott,
Aroid. (1856 1857) 21 25, t.31 56 & Gen.
Aroid. (1858) 95 & Prodr. Syst. Aroid. (1860) 558 575;
Benth., Fl. Hongkong. (1861) 344 345; Engl., in A. &
C. DC, Monogr. Phanerogam., 2 (1879) 78 94; Benth. &
Hook.f., Gen. Pl., 3(2) (1883): 999; Engl. & in Engl. &
Prantl, Naturl. Pflanzenfam. (1889) 113 114 & in Engl.,
Pflanzenr. 21 (IV.23B) (1905) 21 44; Gagnep. in Lecomte,
Fl. Gén.lIndo-Chine, 6 (1942) 1082 1090; F.C.
How, Fl. Kwangchow (Canton) [= Guangzhou] (1956) 693 694;
P.H. HÈ, Cây-cÀ Miê__ Nam Vi_t-nam [Fl.
South Vietnam in Vietnamese] (1960) 690, pl.267 pr. pte;
Fl. Hainan., 4 (1977) 130 131; S.Y. Hu, Dansk Bot. Arkiv,
23(4) (1968) 413 414; C.Y. Wu & H. Li, in C.Y. Wu &
H. Li, Fl. Yunnan., 2 (1979) 740 744; H. Li in C.Y. Wu &
H. Li, Fl. Reip. Pop. Sinicae 13(2) (1979) 15 21, pl.3; J.
Zhong, Ill. Limestone Mount. Pl. Guangxi (1982) 291 292;
M.L. Sai in Y.K. Li et al., Fl. Guizhou., 6 (1987) 545 549;
P.H. HÈ, CâaycÀ Vi_tnam [Ill. Fl. Vietnam
in Vietnamese & English], 3(1) (1993) 420 423, pl.8251
8262. Type: Pothos scandens L. [Tapanava
Adanson, Fam. 2 (1763) 470, nom. illeg. Type: Based on the
same type as Pothos.] Tapanava Raf., Fl. Tellur. 4 (1837)
14. Type: T. chinensis Raf. [= Pothos chinensis (Raf.)
Merr.]
Goniurus Presl, Epimel. Bot. (1851, 1849) 244.
Type: G. luzonensis Presl [= Pothos luzonensis (Presl) Schott]
[Potha O. Kuntze, Rev. Gen. 2 (1891) 742, orth. var.]
Small to very large, very slender to robust, probably
rarely secondarily hemiepiphytic (see Croat 1990; Putz & Holbrook
1986), root climbing, homeo- or heterophyllous, tough, fibrous lianes,
usually with clearly differentiated, adherent, physiognomically
monopodial (see Boyce 1998) non-flowering and free, sympodial or
physiognomically monopodial flowering shoots, the latter often highly
ramified; seedling, where known, a cataphyll-bearing but otherwise
leafless, photosynthesising thread-like eocaul; adult plants often
producing flagelliform, leafless (cataphyll-bearing), skototropic,
foraging shoots; juvenile plants sometimes shingle-leaved (subg.
Allo Pothos; juveniles not described for most species and
this feature not yet reported for many Thai and Indochinese Pothos);
internodes (except at the beginning of branches) much longer than
thick, nodes on free shoots occasionally bearing spines [modified
rudimentary roots according to Hay (1995)], this feature absent
from species in review area; leaf blades simple, entire, very narrowly
lanceolate to broadly ovate, often asymmetrical (subg. Allo Pothos),
with reticulate venation, the primary lateral veins on each side
of the midrib traversed within the margin by one or more intramarginal
veins running ± from the base and about midway along the
midrib to the apex or first to the distal margins and then to the
apex; petiole either with a narrow, ± clasping sheath and
a conspicuous apical geniculum (subg. Allo Pothos), or broad,
flattened and lamina-like with a small apical articulation, the
leaf then resembling that of some Citrus (subg. Pothos);
inflorescences occasionally solitary and terminal on leafy branches,
more usually arranged on lateral short shoots bearing cataphylls,
the short shoots usually simple with a single inflorescence, sometimes
elaborated by sympodial branching into usually leafless, sometimes
highly complex, compact or lax synflorescences bearing two to many
inflorescences flowering in series, synflorescences borne along
or at the end of leafy branches or, when present, on older leafless
parts of the stem, sometimes arising from there; spathe mostly rather
inconspicuous (exceptions in the review area include, e.g., P.
kingii), ovate to lorate, opening wide and held away from
the spadix, often fully reflexed, green to dirty white or yellow
or deep purple; spadix sessile or stipitate, tapering-cylindrical
to spherical; flowers bisexual, with a perianth of usually 6, rarely
4, free tepals or the perianth completely united and the flowers
sunken in pits on the spadix with the perianth resembling a centrally
perforated operculum over the pit (this condition not occurring
in the review area); stamens 6, rarely 4, with flattened filaments
and extrorse dehiscence, thecae elongate to globose; ovary trilocular,
the locules uniovulate, ovules anatropous on an axile placenta at
the base
of the septum; stigma punctiform, discoid-hemispheric or umbonate,
mostly sessile; fruit a 1 3-seeded berry ripening dark green
through yellow to variously red, individually distinct and, relative
to spadix, very large; seed large, exalbuminous, testa smooth; embryo
macropodous. Pollen monosulcate, ellipsoid-oblong, small [mean 21
µm., range 16 25 µm. (Grayum 1984)], exine foveolate
to reticulate or subrugulate, muri-psilate or minutely tuberculate.
2n = 24, 36 (Petersen 1989).
Distribution Approximately 70 species distributed from Madagascar
to Vanuatu and from China (as far north as Hubei) to Australia (as
far south as New South Wales).
Habitat Bole climbing, occasionally lithophytic, root-climbing
lianes or rarely secondary hemiepiphytes in low to upper-mid-elevation
tropical or subtropical seasonal to perhumid evergreen forest.
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