International Aroid Society
 

The Genus Amydrium (Araceae: Monsteroideae: Monstereae)

with Particular Reference to Thailand and Indochina


Nguyen Van Dzu1 and Peter C. Boyce2

1Herbarium, Department of Botany, Institute of Ecology & Biological Resources,
NCNST, Nghia Do, Tu Liem, Hanoi, Vietnam.
2Herbarium, Royal Botanic Gardens Kew, Richmond, Surrey, TW9 3AB, U.K.

Summary. Amydrium is recorded as a new generic record for Vietnam with two species, A. hainanense and A. sinense, hitherto known only from China (including Hainan). Neither species was treated in the last revision of Amydrium (Nicolson 1968) and their recognition requires alterations to his account. An expanded generic description, keys to fertile, sterile and juvenile plants and a review of the genus in Thailand and Indochina (the latter sensu Boyce, in press) are presented. Both newly recorded Vietnamese species are illustrated.

Introduction

Amydrium Schott, a genus of terrestrial subscandent herbs and root-climbing lianes occurring from Sumatera to New Guinea and from southern China to Java, was last revised by Nicolson (1968). Nicolson merged Epipremnopsis Engl. into then monotypic Amydrium and recognized four species in all. Since Nicolson’s account two distinct additional species have been recognized: A. sinense (Engl.) H. Li and A. hainanense (C.C. Ting & C.Y. Wu ex H. Li et al.) H. Li. Amydrium sinense, based upon Engler’s Scindapsus sinense (Engler 1900), was overlooked by Nicolson as belonging to Amydrium although he had seen the type specimen in Berlin. Amydrium hainanense, described initially in Epipremnopsis (Li et al. 1977), was transferred to Amydrium in the Flora of China Araceae treatment (Li 1979). Additionally, two species recognized by Nicolson, A. zippelianum and A. magnificum, have since been shown to be conspecific (Boyce 1995). Amydrium as here defined comprises five species.

Amydrium is in Monsteroideae tribe Monstereae sensu Mayo et al. (1997). Engler (1905) placed Amydrium (then monotypic; A. humile Schott) in Monsteroideae but Epipremnopsis in Pothoideae. Indeed, Amydrium (sensu Nicolson) is sometimes considered intermediate between Pothoideae and Monsteroideae. However, while Amydrium is in some respects somewhat anomalous in Monsteroideae (ripe fruits without abscising stylar region and very sparse trichosclereids), it is considerably atypical in Pothoideae, (swiftly deciduous spathe, prescence of trichosclerieds, and aperigoniate flowers). More work, ideally involving detailed macromolecular comparison of species of Monsteroideae and Pothoideae, is needed to place Amydrium with more certainty (cf. the situation with Anadendrum Schott and Heteropsis Kunth).

Identification

Liane aroids are often collected under incorrect names in Asia (see, e.g. Boyce 1998 for further discussion.) Part of the problem with accurate identification arises from an apparent lack of readily observable critical characters, a difficulty exacerbated by the tendency of key writers to concentrate on difficult to observe fertile characters and interpretatively ambiguous vegetative characters. We have tried to concentrate on readily observable characters in the keys presented here. In particular the feature typical of most monsteroid genera, trichosclereids, has been used. All monsteroid genera except Amydrium have abundant trichosclereids (sparse and scattered in Amydrium). These are readily observable by tearing a mature leaf lamina and looking for ‘hairs’ protruding from the damaged edges and are extremely reliable in asia as a means of assigning a genus to the tribe Monstereae. For a discussion on identifying lianes of the tribe Potheae we refer you to Boyce (1998). We hope that the keys presented below go some way towards easing the identification of liane aroids to genus in Asia.


Key to the Genera of Anadenreae and Monstereae in Thailand and Indochina

1. Inflorescence small; spathe mostly less than 9 cm long just prior to opening . . 2

Inflorescence moderate to large; spathe mostly more than 9 cm long just prior to
opening . . . . . . . . . . . 4

2. Spathe in bud slender, long-slender-pedunculate, conspicuously long-beaked (beak to
1/3 length of entire spathe), opening with inside white, greenish white or purple and
conspicuously glossy-waxy. Flowers with a membranous perigon of fused tepals (i.e. flowers
perigoniate). Ripe fruits berry-like, dark red. Trichosclereids absent . . Anadendrum

Spathe in bud stout, short to long-pedunculate, not conspicuously long-beaked, or if beak
present then less than 1/6 length of entire spathe, opening with inside yellow, greenish or
white, only moderately waxy. Flowers naked (i.e. flowers aperigoniate). Ripe fruits not berry-
like, stylar region mostly abscising to reveal ovary cavity, if berry-like and stylar region not
abscising then fruits ripening white or orange. Trichosclereids present (but sparse in Amydrium)
. . . . . . . . . . . . 3

3. Trichosclereids abundant (many ‘hairs’ apparent when a mature leaf lamina is torn). Leaf with
petiole broadly canaliculate, sheath margins broad, spreading, persistent, extending to apical
geniculum; leaf lamina thinly coriaceous, often variegated silvery grey. Ripe fruits with stylar
region abscising . . . . . . . . . Scindapsus

Trichosclereids sparse (very few ‘hairs’ apparent when a mature leaf lamina is torn). Leaf with
petiole narrowly canaliculate or terete, sheath margins narrow, erect or slightly inrolled, soon
drying and degrading into weak fibres, then falling to leave an obscure scar, sheath either
ligulate with free ligules extending beyond apical geniculum or sheath at most extending only
to half way along petiole, if the latter then remainder of petiole terete with two prominent
adaxial keels extending to apical geniculum; leaf lamina variously-textured. Ripe fruits with
stylar region not abscising . . . . . . . Amydrium

4. Trichosclereids sparse (very few ‘hairs’ apparent when a mature leaf lamina is torn). Higher
order venation completely reticulate. Ovary 1-locular, placenta 1, intrusive-parietal, ovules 2.
Ripe fruits with stylar region not abscising . . . . . Amydrium

Trichosclereids abundant (many ‘hairs’ apparent when a mature leaf lamina is torn). Higher
order venation striate or reticulate. Ovary never as above combination. Ripe fruits with stylar
region abscising . . . . . . . . . . 5

5. Ovules solitary, placentation basal. Fruits with a solitary seed . . . Scindapsus

Ovules 4 – 6 or more, placentation intrusive-parietal. Fruits with more than one seed . . . .6

6. Ovules 8 or more, superposed on 2 (rarely 3) intrusive parietal placentas. Seeds many,
ellipsoid, straight, 1.3 – 3.2 mm long, 0.6 – 1.0 mm wide; testa brittle, smooth . . . . . Rhaphidophora

Ovules 4 (– 6) at base of a single intrusive parietal placenta. Seeds few, curved, 3 – 7 mm long,
1.5 – 4.0 mm wide; testa bony and ornamented . . . . . Epipremnum


Amydrium Schott, Ann. Mus. Bot. Lugduno-Batavum 1: 127 (1863); Engl. in DC., Monogr. Phanerogam. 2: 250 (1879); Engl. & K. Krause in Engl., Pflanzenreich 37 (IV.23B): 118 (1908); Ridl., Fl. Mal. Pen.5: 118 – 119 (1925); Nicolson, Blumea 16(1): 123 – 127 (1968); Backer & Bakh.f., Fl. Java 3: 104 – 105 (1968); H. Li in C.Y. Wu & H. Li, Fl. Reip. Pop. Sinicae 13 (2): 22 – 26, Pl. 4, 8 – 16(1979); A. Hay in Johns & A. Hay, Student’s Guide Monocot. Papua New Guinea. Part 1, 47 – 49, Fig. 18 (1981); M.L. Sai in B. Zhu et al., Fl. Guizhou. 6: 549 – 550, Fig. 162 (1987); P.C. Kao in P.C. Kao & Z.M. Tan, Fl. Sichuan. 9: 380 – 382, Pl. 120 1 – 3 (1989); A. Hay, Aroids of New Guinea, 47 – 48, Pl. VIII, c (1990); Mayo, Bogner & P.C. Boyce, Genera of Araceae, 116 – 118, pl. 13, pl. 113 A (1997). Type species: A. humile Schott.

Epipremnopsis Engl. in Engl, Pflanzenreich 37 (IV.23B): 1 – 3 (1908); Merr., Enum Philipp. Pl. 1:
177 – 178 (1922); Ridl., Fl. Mal. Pen. 5: 120 (1925); H. Li et al., Acta Phytotax. Sin. 15(2): 102,
fig. 15, 1.(1977); Fl. Yunnan 2: 745 – 747, Pl. 203, 8 – 16 (1979). Type species: E. media
(Zoll. & Moritzi) Engl.

Small to medium-sized, occasionally very large, root-climbing lianes (sensu Schimper 1903) or creeping to scandent herbs, most but not all species producing long (foliage-) leafless flagelliform foraging shoots; trichosclereids sparsely present in vegetative parts (only petiole and sheath fide Seubert 1996), more abundant in style (fide Carvell 1989). Leaves: foliage leaves often remote from one another, interspersed with few to rather many cataphyll-bearing nodes; petiole geniculate apically and basally, sheath very short (barely exceeding basal geniculum) to usually less than half as long as petiole, occasionally reaching apical geniculum, rarely ligulate and exceeding it; lamina ovate-cordate to lanceolate or pandurate-trilobed or pinnatifid to pinnatisect, sometimes with ± numerous round to oval perforations; primary lateral veins pinnate, running into marginal vein, higher order venation reticulate. Inflorescence 1–several in each floral sympodium, terminal on shoot but often displaced by sympodial branching and, in fruit, appearing lateral on stem; peduncle erect, subequal or half as long as petiole; spathe conchiform to ovate or canoe-shaped, apiculate, often thick-textures, sometimes reflexed at anthesis and then deciduous; spadix sessile to long-stipitate, sometimes very short. Flowers bisexual, aperigoniate. Stamens 4 – 6, free, filaments short, broadly linear, anthers equalling or shorter than filaments, thecae ovoid, extrorse, dehiscing by a longitudinal slit. Pollen fully zonate, hamburger-shaped, medium-sized (mean 39 µm., range 38–41 µm.), exine either densely and minutely punctate in one half and virtually psilate in the other, or uniformly foveolate-fossulate, apertural exine psilate or obscurely verrucate (pollen details from Grayum 1984, 1992). Gynoecium obpyramidal or obconoid, tetragonal, ovary 1-locular, ovules 2, funicle anatropous, short, placenta situated near the base of a deeply intrusive septum, stylar region broader than ovary, slightly prominent centrally below stigma, otherwise ± truncate, stigma small, hemispheric to longitudinally elongate. Infructescence comprised of numerous medium to large berries; fruits subglobose, truncate to domed at apex, white (A. medium, A. humile) or orange-red (A. zippelianum, A. sinense) when ripe; stylar region not abscising (q.v. Epipremnum, Boyce 1998). Seed subglobose to heart-shaped, testa smooth, glossy, embryo curved and partly green, endosperm present (fide Seubert 1993). Chromosomes 2n = 60.

Distribution. 5 spp. from tropical and subtropical east Asia: Brunei, P.R. China (Guandong, Guangxi, Guizhou, Hainan, Hubei, Hunan, Sichuan, Yunnan), Indonesia (Irian Jaya, Java, Kalimantan, Maluku, Sulawesi, Sumatera), Malaysia (Peninsula, Sabah, Sarawak), Myanmar, Papua New Guinea, Philippines, Singagpore, Thailand, Vietnam.


Keys to Amydrium:

Key to herbarium material

1. Leaf lamina of flowering shoots entire . . . . . . . 2
Leaf lamina of flowering shoots pinnatifid, pinnatipartite, pinnatisect or, if entire, then with
perforations . . . . . . . . . . 3

2. Base of leaf lamina cordate; flowering shoots not adherent-climbing (i.e., no clasping roots
visible along stem) (Peninsular Malaysia; Sumatera). . . . . 2. A. humile

Base of leaf lamina cuneate to briefly decurrent; flowering shoots adherent-climbing (i.e.,
clasping roots visible along stem (P.R. China, N Vietnam) . . . 4. A. sinense

3. Leaf lamina of flowering shoots pinnatifid or pinnately divided, if pinnatifid then sometimes
perforated . . . . . . . . . . . 4

Leaf lamina of flowering shoots entire, moderately to greatly perforated (P.R. China (incl.
Hainan), N Vietnam) . . . . . . . 1. A. hainanense

4. Leaf lamina of flowering shoots pinnatifid to pinnatipartite, almost always perforated
. . . . . . . . . . . 3. A. medium

Leaf lamina of flowering shoots pinnatipartite to pinnatisect, never perforated
. . . . . . . . . . 5. A. zippelianum


Field key to fertile specimens

1. Plants always flowering on adherent-climbing shoots . . . . . 2

Plants mostly flowering on non-climbing shoots, if flowering shoots climbing then never
adherent (Peninsular Malaysia; Sumatera) . . . . . 2. A. humile

2. Leaf laminae of flowering shoots entire, perforated or not . . . . 3

Leaf laminae of flowering shoots pinnatifid, pinnatipartite or pinnatisect, sometimes perforated. . . . . 4

3. Leaf lamina moderately to greatly perforated . . . . . 1. A. hainanense

Leaf lamina never perforated . . . . . . . 4. A. sinense

4. Leaf lamina perforated, segments spreading, lamina seldom exceeding 50 cm in length; small
plants lacking net-like fibres on the apicies of flowering shoots; ripe infructescences white
(Myanmar, Thailand, Cambodia, Vietnam?, Peninsular Malaysia, Singapore, Sumatera, Java,
Borneo, Philippines, Maluku) . . . . . . . 3. A. medium

Leaf lamina not perforated, segments drooping, lamina often exceeding 75 cm in length; large
plants with copious net-like fibres on the apicies of flowering shoots; ripe infructescences dark
orange-red (Philippines, Sulawesi, Maluku, New Guinea) . . 5. A. zippelianum

Field key to sterile and juvenile specimens

1. Plants without adherent climbing stems . . . . . . . 2

Plants with adherent climbing stems . . . . . . . 8

2. Leaves entire, with or without perforations . . . . . . 3

Leaves variously divided, with or without perforations . . . . . 7

3. Leaf base cordate . . . . . . . . . . 4

Leaf base rounded to cuneate . . . . . . . 4. A. sinense

4. Leaf lamina thinly coriaceous . . . . . . . . 5

Leaf lamina thickly coriaceous . . . . . . . 2. A. humile

5. Petiolar sheath extending almost to apical geniculum. Leaf lamina lanceolate, often with
perforations. Stems smooth . . . . . . 1. A. hainanense

Petiolar sheath short, often not exceeding basal geniculum, never extending more than half way
along petiole. Leaf lamina various. Stems various . . . . . 6

6. Leaf lamina mostly ovate, never with perforations. Stems rough. . . 4. A. sinense

Leaf lamina broadly ovate to oblong-lanceolate, occasionally with a few perforations. Stems
smooth . . . . . . . . . . 3. A. medium

7. Leaf pinnatipartite to pinnatisect, never perforated . . . 5. A. zippelianum

Leaf pinnatifid to pinnatipartite, almost always perforated . . . 3. A. medium

8. Apicies of adherent stems with copious net-like fibres, large plants, leaf lamina often exceeding
75 cm in length; (Philippines, Sulawesi, Maluku, New Guinea) . . 5. A. zippelianum

Apicies of adherent stems without net-like fibres, although cataphylls sometimes degrading into
weak, free fibres or if net-like fibres present then lamina segments drooping . . 9

9. Leaf lamina entire, much perforated . . . . . 1. A. hainanense

Leaf lamina not as above . . . . . . . . . 10

10. Leaf lamina entire, never perforated . . . . . . 4. A. sinense

Leaf lamina pinnatifid, pinnatipartite or pinnatisect, perforated on not . . . 11

11. Leaf lamina pinnatisect or pinnatipartite, never perforated, segments drooping, lamina often
exceeding 75 cm in length; large plants with copious net-like fibres at the apicies of adherent
shoots; (Philippines, Sulawesi, Maluku, New Guinea) . . . 5. A. zippelianum

Leaf lamina pinnatifid or pinnatipartite, almost always perforated, segments spreading, lamina
seldom exceeding 50 cm in length; small plants lacking net-like fibres at the apicies of
adherent shoots; (Myanmar, Thailand, Cambodia, Vietnam?, Peninsular Malaysia, Singapore,
Sumatera, Java, Borneo, Philippines, Maluku) . . . . . 3. A. medium

Conspectus of species

1. Amydrium hainanense (C.C. Ting & C.Y. Wu ex H. Li et al.) H. Li in C.Y. Wu & H. Li, Fl. Reip. Pop. Sinicae 13(2): 24, Pl. 4, 11 - 16 (1979). Type: Hainan, X.Q. Liu 26378 (GUIZ n.v. (photograph of type in Acta Phytotax. Sin. 15(2), Pl. 5, 1!))

Epipremnopsis hainanensis C.C. Ting & C.Y. Wu ex H. Li et al., Acta Phytotax. Sin. 15(2): 102
(1977); Fl. Yunnan 2: 747, Pl. 203, 11 – 16 (1979).

Large root-climbing liane to 5 m. Stem stout on climbing shoots, up to 1.5 cm diam., internodes 2–3 cm long, epidermis smooth. Foliage leaves clustered, only interspersed with cataphyll-bearing nodes on juvenile, terrestrial stems; petiole moderately robust, apical geniculum prominent, 20 – 30 cm on climbing shoots, on juvenile branches 4 – 5 cm, sheath narrow, reaching base of leaf lamina, base amplexicaul, sheath early caducous, falling to leave a prominent scar; leaf lamina ovate-lanceolate to falcate-lanceolate, entire, chartaceous, 25 – 45 ¥ 8.5 – 17.3 cm on climbing shoots, 13 – 17 x 5 – 6.5 cm on juvenile branches, lamina usually with large and small, ovate or oblong, 4 – 6 cm x 1.5 – 4 cm perforations, these sometimes reaching margin and midrib, apex abruptly acuminate, base oblique-rounded to oblique sagittato-cordate, posterior lobes frequently of unequal size, primary lateral veins numerous, prominent abaxially, ascending and arched, lamina mid-green when fresh, drying dark brown to almost black. Inflorescence solitary; peduncle terete, stout, 8 – 10 cm x c. 4 mm diam., epidermis smooth; mid-green; spathe shortly cymbiform, 8 – 5 ¥ 8 – 9 cm, apex rostrate, yellow-red; spadix stipitate; stipe 3 – 10 mm; fertile portion of spadix cylindric, 4.3 –6 x 1.3 – 1.5 cm diam., apex obtuse, base subtruncate; Flowers: stamens 6; ovary hexagonal, cylindric; stylar region truncate, 3 ¥ c. 2.5 mm; stigma sessile, longitudinally oblong. Figs 1, 2.

Distribution. China (Guangdong, Guangxi, Hainan, Hunan and Yunnan fide H. Li 1979); N Vietnam (Ha Tay).

Selected specimens seen.
CHINA. Yunnan: 28 Sept. 1980 (fl.), [collector not translated] 134 (KUN).
VIETNAM. Ha Tay: Ba Vi, c. 80 km W of Hanoi, 21° 03’N, 105° 21’E, 19 July 1995 (sterile), V.D. Nguyen & Croat 77830 (HN, MO) & 5 March 1997 (sterile), Boyce 1150 (HN, K, M) & 25 Sept. 1998 (fl., fr.) V.D. Nguyen s.n. (HN, K).

Ecology. Dense wet hill to montane forests, slopes or beside water, creeping on trees or over rocks. Alt. 300 - 1600 m.

Phenology. Flowering April (Hainan) - October (Guangxi); fruiting September (Ha Tay).


2. Amydrium humile Schott, Ann. Mus. Bot. Lugduno-Batavum 1: 127 (1863); Engl. & K. Krause in Engl., Pflanzenreich 37 (IV.23B): 118 (1908); Nicolson, Blumea 16(1): 123 – 127 (1968); Mayo, Bogner & P.C. Boyce, Genera of Araceae, pl. 13 M, (1997). Type: Indonesia: Sumatera, Korthals (holotype L!).

Epipremnum humile (Schott) Hook.f., Fl. Brit. Ind. 6: 559 (1893); Rhaphidophora humilis (Schott)
Ridl., Mat. Fl. Malay Pen. 3: 41 (1908) (‘humile’).

Distribution. Indonesia (Sumatera), Malaysia (Peninsular).


3. Amydrium medium (Zoll. & Moritzi) Nicolson, Blumea 16: 124 (1968); Mayo, Bogner & P.C. Boyce, Genera of Araceae, pl. 13 A - H, pl. 113 A (1997). Type: Indonesia: Java, 25 Dec. 1842 (fl.), Zollinger 982 (holotype L!; isotypes B!, FI!, G, P!).

Scindapsus medius Zoll. & Moritzi, Syst. Verz., 82 (1846); Anadendrum medium (Zoll. & Moritzi)
Schott, Bonplandia 5: 45 (1857); Epipremnum medium (Zoll. & Moritzi) Engl. in A. & C. DC.,
Monogr. Phanerogam. 2: 250 (1879); Epipremnopsis media (Zoll. & Moritzi) Engl. in Engl.,
Pflanzenreich 37 (IV.23B): 1 (1908)
Rhaphidophora huegelii Schott, Bonplandia 5: 45 (1857); Scindapsus huegelii (Schott) Ender, Index
Aroid. 74 (1864); Epipremnopsis huegelii (Schott) Engl. in Engl., Pflanzenreich 37 (IV.23B): 138
(1908) (‘huegeliana’). Type: Philippines: Luzon, Manilla Huegel (W).
Epipremnum truncatum Engl. & K. Krause in Engl., Pflanzenreich 37 (IV.23B): 63 (1908). Type:
Philippines: Leyte, Palo, Jan. 1906 (fr.), Elmer 7291 (holotype B!; isotype L!).
Epipremnopsis subcordata M. Hotta, Acta Phytotax. Geobot. 22: 2 (1966). Type: Malaysia:
Sarawak, Bintulu, about 8 km east from Minah Camp, along survey route from Sg. Minah, 19
Oct. 1963 (fr.), Hirano & Hotta 347 (holotype KYO!).
[Rhaphidophora kerrii Gagnep., nom. nud. in sched. K et P]

Distribution. Brunei Darussalam, Indonesia (Java, Kalimantan, Maluku, Sumatera), Malaysia (Peninsular, Sabah, Sarawak), Myanmar, Philippines, Thailand.

Selected Thai and Indochinese Specimens seen.
MYANMAR. Tenasserim: Zimba Valley, 24 Nov. 1924 (fl.), Parker 2273 (K).
THAILAND. SW37 Kanchanaburi: Kwae Noi river basin, Neeckey, near Wangka, 13 May 1946 (fr.), Kostermans 413 (K). PEN63 Chumpon: 40 km south of Chumpon, 24 March 1971 (sterile), Bogner 433 (K). PEN65 Surat Thani: Ban Yao, 23 Feb. 1930 (fl.), Kerr 18232 (K). PEN68 Krabi: Kaw Pa, 13 April 1930 (fl./fr.), Kerr 19404 (K). PEN69 Nakhon Si Thammarat: Lansaka, Kamjan, Khao Luang N.P., SE side, 24 March 1993 (fl., fr.), Chantaranothai et al. 1366 (K, KKU, TCD); Tung Song, 18 Feb. 1928 (fr.), Put 2373 (K). PEN71 Trang: Khao Chong, 9 Oct. 1970 (fl., fr.), Charoenphol et al. 3503 (K); Khao Chong F.S., 17 Jan. 1962 (fl.), Nicolson 1701 (K).


4.Amydrium sinense (Engl.) H. Li in C.Y. Wu & H. Li, Fl. Reip. Pop. Sinicae 13 (2): 23, Pl. 4, 8 - 10 (1979); M.L. Sai in B. Zhu et al., Fl. Guizhou. 6: 549 – 550, Fig. 162 (1987); P.C. Kao in P.C. Kao & Z.M. Tan, Fl. Sichuan. 9: 380 – 382, Pl. 120 1 – 3 (1989). Type: China, Sichuan, Nan chuan, Sept. 1891 (fr.), Rosthorn 758 (holotype B!).

Scindapsus sinensis Engl., Bot. Jahrb. 29: 234 (1900); Engl. & K. Krause in Engl., Pflanzenreich
37 (IV.23B): 80 (1908); Epipremnopsis sinensis (Engl.) H. Li, Acta Phytotax. Sinica 15(2): 102
(1977); Fl. Yunnan 2: 745 – 747, Pl. 203, 18 – 10 (1979).
Rhaphidophora dunniana H. Lév., Feddes Rep. Sp. Nov. 9: 325 (1911); Rehder, J. Arn. Arb. 17:
57 (1936). Type: China, Guizhou, Feb. 1905, Esquirol 246 (holotype (fl.) E!; isotype (sterile)
K!).

Creeping and root-climbing liane to 8 m. Stem slender, 3–5 mm diam. internodes 3–5 cm long, epidermis rough. Foliage leaves scattered, interspersed with few to rather many cataphyll-bearing nodes; petiole slender, 5.5 – 9 (-15) cm, sheath narrow, extending to c. half way along petiole, soon degrading into free fibres and falling to leave an obscure scar; (foliage) leaf lamina oblong-ovate to oblong-lanceolate, entire, stiffly chartaceous to coriaceous, 9 – 23 ¥ 4 – 8 cm, apex acute, base rounded, cuneate to cordate (the latter in juvenile leaves), slightly to strongly asymmetric, light green when fresh, after drying dark brown to black-brown; lateral veins many, diverging at c. 30º from midrib, reaching and forming a very narrow marginal vein. Inflorescence solitary; peduncle terete, stout, 3.5 – 6 cm x 2 – 3 mm diam., epidermis rough, pale green; spathe fusiform in bud, c. 7 x c. 2.2 cm at widest point green, opening cymbiform, subovate, 8 – 9 x 11.5 cm (i.e. wider than long), notably thickened, soon falling to leave a prominent wide scar, yellow-green to yellow; spadix stipitate; stipe 5 – 10 mm; fertile portion of spadix obovoid, c. 4 x 1.8 cm, apex obtuse, narrowed towards the base. Flowers: filaments 4 mm long, anthers oblong, 3 mm long; ovary 5–6-angular, cylindric, 4 ¥ 5 mm, stylar region truncate; stigma sessile, nearly circular. Fruits green ripening through yellow to orange-red, malodorous (fide H. Li (1979) but (fide Dzu, pers. obs.). pleasently smelling and sweet tasting. Seeds 1 – 2, brown, obovate, kidney-shaped, 2 mm long. Fig. 3.

Distribution. China (Guangxi, Guizhou, Hubei, Hunan, Sichuan and Yunnan fide H. Li 1979); N Vietnam (Ha Giang).
Selected Indochinese Specimens Seen.
CHINA. Guangxi: Ling-yun, 13 July 1937 (sterile), X. Liu 28605 (MO); Nam dan, 7 Oct. 1937 (fr.), Z. Huang 410?8 (MO); no further data (fr.), C. Wang 41058 (GH). Guizhou: Feb. 1905 (sterile), Esquirol 246 (holotype of Rhaphidophora dunniana K); 25 July 1983 (fl.), Xiang Qian Team 2461 (KUN). Yunnan: Houang Tsao-pa (juvenile) Cavalerie 7372 (E, K); Xichou, Fadou, 28 Sept. 1960 (fl.), H. Li 142 (KUN).
VIETNAM. Ha Giang: Dong Van, 12 Nov. 1997 (fr.), V.D. Nguyen 214 (HN); Hoang Su Phi, Ho Thau, on the road to Chin lung thy, 16 Nov. 1997 (fr.), V.D. Nguyen 221 (HN).
Ecology. Evergreen forests, terrestrial, climbing on trees or over rocks. Alt. 550 – 1900 m.
Pkhenology. Flowering June – July; fruiting July – November.
Ethnobotany. The stems and leaves are used for treating traumatic injury, fractures and angina pectoris (H. Li 1979).


5. Amydrium zippelianum (Schott) Nicolson, Blumea 16: 126 (1968); A. Hay, Aroids Papua N. Guinea, 47 (1990); P.C. Boyce, Curtis’s Bot. Mag. 12(2): 85 – 89, Plant portrait 269 (1995); Mayo, Bogner & P.C. Boyce, Genera of Araceae, pl. 13 J – K (1997). Types: 'New Guinea', Zippel s.n. (L 898!, L 894!, W! Schott's Icones Aroideae 2977 [drawing of type with inflorescence intact]).

Rhaphidophora zippeliana Schott, Ann. Mus. Lugd.-Bat. 1: 129 (1863); [Pothos miniata Zipp. ex
Miq., Ann. Mus. Bot. Lugd.-Bat 1: 130 (1863), nom. superfl. pro. Rhaphidophora zippeliana
Schott]; Epipremnum zippelianum (Schott) Engl., Bot. Jahrb. Syst. 1: 182 (1880); Engl. in
Beccari, Malesia 1: 274, t. 20, fig. 10 – 12 (1882); Epipremnopsis zippeliana (Schott) Alderw.,
Bull. Jard. Bot. Buitenzorg sér.3, 4(5): 378 (1920).
Epipremnum asperatum Engl., Bull. Soc. Tosc. Ortic. 4: 270 (1879). Types: Papua New Guinea,
Fly River, 1876, d’Albertis s.n. (FI!); Indonesia, Moluccas, Ternate, Aequi Conora, Sept. 1874,
Beccari P.M. s.n. (FI!).
Epipremnum magnificum Engl., Bull. Soc. Tosc. Ortic. 4: 270 (1879); ); Engl. in Beccari, Malesia
1: 274, t. 20, fig. 6 – 9 (1882); Epipremnopsis magnifica (Engl.) Alderw., Bull. Jard. Bot.
Buitenzorg sér.3, 4(2): 330 (1922); Amydrium magnificum (Engl.) Nicolson, Blumea 16: 125
(1968). Lectotype (selected by Nicolson, 1968): Indonesia, Sulawesi, Penisola SE a Lepo-Lepo
presso Kandari, July 1874, Beccari P.S. s.n. (B!, FI!).
Rhaphidophora warburghii Engl., Bot. Jahrb. Syst. 37: 116 (1905). Type: Philippines: Luzon,
1888 (fl.), Warburg s.n. (holotype B!).
Epipremnum elmerianum Engl. in Engl., Das Pflanzenr. 37 (IV.23B): 66 (1908). Type:
Philippines: Lyete, near Palo, Jan.1906 (fr.), Elmer 7295 (holotype B!, isotypes BO!, G!, K!).
Epipremnum philippinense Engl. & K. Krause in Engl., Das Pflanzenr. 37 (IV.23B): 137 (1908).
Types: Philippines: Luzon, Tayabas prov., Lucban, May 1907 (fr.), Elmer 7623 (B!), Elmer 9253
(B†, PNH†).
Epipremnum luzonense K. Krause, Bot. Jahrb. Syst. 45: 659 (1911). Type: Philippines: Luzon,
Laguna prov., near Paete, July 1909, Ramos PNH 10052 (PNH†).
Epipremnum mampuanum Alderw., Bull. Jard. Bot. Buitenzorg sér.3 1(5): 378 (1920). Type:
Sulawesi, Mt. Mampoe, van Vuuren sub. Alderwerelt 251 ex. cult Bogor Bot. Gard. (BO)
[Epipremnum miniatum Elmer ex Merr., Leafl. Philipp. Bot. 10(133): 3622 (1938) nom. nud. sine
descr. Latin. ; Elmer, Enum. Philipp. fl. pl. 1: 177 (1923) nomen. Based on: Philippines: Luzon,
Sorsogon prov., Irosin (Mt Bulusan), Oct. 1915, Elmer 14522 (K!, PNH†, US); Philippines:
Luzon, Sorsogon prov., Irosin (Mt Bulusan), Nov. 1915, Elmer 15113 (K!, P!, US); Philippines:
Luzon, Sorsogon prov., Irosin (Mt Bulusan), June 1916, Elmer 16422 (K!, PNH†, US)].
[Epipremnum sorsogonense Elmer ex Merr., Enum. Philipp. fl. pl. 1: 177 (1923) nom. nud. sine
descr. Latin. Type: Philippines: Luzon, Sorsogon prov., Irosin (Mt Bulusan), June 1916, Elmer
16422 (K!, PNH†, US)].

References

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——— (1997). The Sclereids of Araceae. Flora 192: 31 – 37.