P. C. BOYCE, 2009 19 The L. (: ) in Thailand

Peter c. Boyce BRT Research Associate Forest Herbarium (BKF) The Office of Forest and Conservation Research National Park Wildlife and Plant Conservation Department 61 Phahonyothin Rd Chatuchak, Bangkok 10900, Thailand

ABSTRACT Pothos L., Sp. PI. 968. 1753; Hook. f., FI. Brit. India 6: 551. 1893; Ridley, FI. Mal. An account of Pothos for Thailand is Penins. 5: 127. 1925; Gagnepain in presented as a precursor of the forthcoming Lecomte (ed.), FI. Gen. I'Indo-Chine 6: Flora of Thailand treatment. Eight species are 1082. 1942; Mayo, Bogner & Boyce, recognized of which two (P. wallichii Genera of Araceae, 98-99, PI. 5 & 108A, Hook.f. & P. neoroxburghii P. C. Boyce) 1997; Boyce, Blumea45: 147-204. 2000; represent new records for Thailand, the latter Boyce & Hay, Telopea 9(3): 449-571. is also a nomen novum for long-overlooked 2001. Type: L. and much obfuscated P. roxburghii de Vriese, nom. illeg. (nonP. roxburghiiSchott). Generic Synonyms: KEYWORDS Tapanava Adanson, Fam. 2: 470. 1763, Araceae, Pothos, Flora of Thailand. nom. illeg. Type: Based on the same type as Pothos Batis Blanco, FI. Filip. INTRODUCTION 791. 1837. Type: B. hermaphodita Blanco. Pothos L. is a of ca. 65 species of Goniurus Presl, Epim. Bot. 244. 1851, subtropical and tropical, predominantly '1849'- Type: G. luzonensis Presl forest, root-climbing hemiepiphytes dis­ [=Pothos luzonensis (Pres\) Schottl tributed from Madagascar to Western [Potha O. Kuntze, Rev. Gen. 2 (1891) Oceania (east to Vanuatu) and China (north 742, orth. var.l to HubeO to (south to Queens­ land, New South Wales). Recent revisions Small to very large, slender to rather have established an alpha- for robust hemiepiphytes. Stems rather woody, Malesia (Hay, 1995; Boyce & Hay, 2001), lower branches rooting, upper ones free Thailand, and Indo-china (Boyce, 2000). and hanging in most species, nodes rarely Boyce (2000) was published as a precur­ bearing short, clustered spines, buds of sory account for the Flora of Thailand but lateral shoots sometimes perforating the then, for a variety of reasons, final collation leaf sheath or ± infra-axillary. Leaves of the Thai Araceae account was delayed distichous, juvenile of some species until last year. While undertaking updating with a shingle form. Petiole pulvinate and final compilation of the aroids, the apically, either broad, completely flattened author discovered two new Thai records and usually auriculate apically, or mor­ for Pothos, including a necessary nomen phology normal with a long sheath, some­ novum. Given that two additional species times sheath reduced to a pair of hyaline represents a more than 30% increase in the ridges. Lamina Iinear-Ianceolate to ovate number of Pothos for Thailand it is felt that or elliptic, mostly sometimes oblique; an updated precursor account is needed. primary lateral veins either mostly arising 20 AROIDEANA, Vol. 32 near base of blade, long arcuate, and usually fornicate, free or partially to running into marginal vein near apex, or completely connate. Stamens 4-6, free, pinnate, weakly differentiated, forming filaments oblong, flattened, connective slen­ submarginal collective vein, 1-2 marginal der, thecae ellipsoid, dehiscing by slit. veins also present and these crossing the Gynoecium with ovary ovoid-oblong or primary lateral veins to produce a distinc­ depressed, (2?-) 3-locular; ovules 1 per tive 'pothoid' venation; higher order locule, anatropous, funicle short, placenta venation reticulate. Inflorescence mor­ axile at base of septum, stylar region phologically axillary or infra-axillary, sol­ sometimes as broad as ovary, stigma dis­ itary or forming short free, very rarely coid-hemispheric to umbonate. Fruit an elongating and rooting, synflorescences ellipsoid to ovoid, berry 1 (-3)-seeded, of several inflorescences, bearing 4-6, or usually red or rarely whitish or dull purple more rigid, coriaceous cataphylls at the when ripe. Seed ellipsoid, testa smooth, base. Peduncle very short to very long, embryo large, endosperm absent. sometimes reflexed. Spathe ovate to line­ Sixty-five species distributed from Mada­ ar, rarely very long, persistent into fruit­ gascar through to India, the subtropical ing. Spadix globose, ovoid, cylindric, eastern Himalayas throughout subtropical ellipsoid or obovoid, sessile to long­ and tropical Asia into the tropical western stipitate, densely or laxly flowered. Flow­ pacific and tropical eastern Australia. Eight ers bisexual, perigoniate; tepals 4-6, species in Thailand, none endemic.

KEY TO THE THAI SPECIES 1. Leaf with petiole expanded and flattened, the leaf resembling that of many Citrus 2. Stipe of spadix sharply bent at anthesis, fertile portion of spadix held adjacent to peduncle; inflorescences generally arising in many leafaxils along a flowering branch ...... 7. P. scandens 2. Stipe of spadix :!: straight at anthesis; inflorescences either few at shoot tips, or arising singly in most axils of a flowering branch. 3. Peduncle not more than 2.5 cm, green or purple; spathe green or purple; spadix stipe never exceeding1.5 cm; fertile portion ovoid, ca. 3.5-13 X 3- 11 mm, white to cream at anthesis 4. Inflorescences few per flowering shoot, mostly at the tips; stipe stout, less than Y4 as long as fertile portion of spadix, spathe green ... 1. P. chinensis 4. Inflorescences many per flowering shoot; arranged along the entire distal portion; stipe slender, equalling or slightly exceeding fertile portion of spadix; spathe purple ...... 6. P. neoroxburghii 3. Peduncle 4-10 cm dull orange-yellow; spathe white; spadix stipe 2.75-4 cm; fertile portion clavate, 12.5-15 X 10-12 mm, mid-yellow ...... 5. P. macrocephalus 1. Leaf with petiole slender, canaliculate 5. Spadix with flowers densely clustered, the whole appearing uniformly cylindrical 6. Spathe deeply cucullate, deep purple; inflorescence carried below the flowering shoot on a sharply deflexed peduncle ...... 3. P. kingii 6. Spathe lorate or lanceolate; inflorescence erect or spreading, peduncle not sharply deflexed 7. Peduncle less than 1 mm diam., arching, inflorescence spreading; spathe 4-5 cm long, lanceolate ...... 8. P. waUichii 7. Peduncle 2-3 mm diam., erect or curving and ultimately ascending, inflo- rescence held erect, spathe 2.5-10 cm long, lorate ...... 4. P.leptostachyus 5. Spadix with flowers scattered along a slender axis ...... 2. P. curtisii p. C. BOYCE, 2009 21

Plate 1. A-B: Pathos cbinensis, Note the inflorescence situated at the tip of the flowering shoot; C: Potbos kingii, showing the diagnostic hooded deep purple spathe; D: Pathos lorispathusi, the erect inflorescences and green, lorate spathe d istinguish this from the somewhat similar P. wallichii. Images: A-B: © Forest Herbarium; C: © D ept. Plant Sciences, Faculty o f Resea rch Science and Technology, Unimas; D : © Peter Boyce. Used w ith permission. 22 AROIDEANA, Vol. 32

1. Pathos chinensis (Raf.) Merr., J. Am. faintly purple-tinged, somewhat waxy; Arb. 24: 210. 1948; Hook.f., Fl. Brit. spadix stipitate; stipe, terete in cross India 6: 552 (sub. P. cathcartii). 1893; section, 5-10 X 1-1.25 mm, erect, straight, Gagnep. in Lecomte, Fl. l'Indo-Chine, green; fertile portion globose to ovoid, 6: 1086-1087 (sub. PP. cathcartii, 3.5-13 X 3-10 mm, pale green to white. yunnanensis & balansae). 1942; Flowers ca. 1-2 mm diam. Infructescence Boyce, Blumea 45: 155. 2000. Type: with 1-5 berries; fruit obclavate to ovoid Bot. Reg. 16 (1830) pI. 1337. or ellipsoid, 1-1.8 X 1-1.4 mm, mid-green Tapanava chinensis Raf., Fl. Tellur. 4: 14. ripening to scarlet, often with basal 1837 chartaceous tepal remains. Pothos seemannii Schott, Aroid. 22, t. 43. 1856-7. - Bonplandia 5: 45. 1857. Ecology Pothos cathcartii Schott, Aroid. 22, t. 44-45. 1858 (as 'cathcartt')o On rocks and trees and in clearings in Pothos warburgii Engl., Bot. Jahrb. Syst. 25: tropical or subtropical primary or disturbed 2.1898. lowland wet or dry evergreen forest, rain­ Pothos balansae Engl., Bot. Jahrb. Syst. 25: forest, sandstone, limestone, granite, clay, 3.1898. loam or sandy soil; altitude: 250-1,970 m. Pothos yunnanensis Engl. in Engl., Pflan­ zenr. 21CIV.23B): 28. 1905. Distribution Pothos chinensis (Raf.) Merr. var. lotienen­ Nepal through NE India and Bhutan, sis c.y. Wu & H. Li, Acta Phytotax. Sin. Bangladesh, Burma to SW China, including 15(2): 101. 1977. Hong Kon, through Thailand, Cambodia, Small to very large, slender to robust, Lao P.D.R., Vietnam, Taiwan. homeophyllous root-climbing hemiepi­ phyte to 10 m. Stem weakly four-angled, Thai Distribution slightly compressed or terete in cross NORTHERN. Chiang Mai, Nan, Lampang, section, mid-green, becoming greyish Phrae, Tak, Phitsanulok, Petchabun, Loei. brown with age; fertile shoot often EASTERN: Nakhon Ratchasima. SOUTH­ branching to three or more orders. Leaves WESTERN: Kanchanaburi. CENTRAL: Sar­ many. Petiole broadly winged, obovate­ aburi. SOUTH-EASTERN: Prachin Buri, oblong to linear-oblong or elongate-trian­ Chantaburi. PENINSULAR: Phangnga gular, 5-14 X .5-2 em, with 2-3 secondary veins and numerous veinlets per side, Notes base decurrent to clawed, apex truncate, rounded or auriculate; lamina ovate to Confusion between P. chinensis, P. elliptic or lanceolate, 3-21 X 1.5-25 em, neoroxburghii, and P. scandens is easy. In leathery, drying chartaceous. Flowering flower P. chinensis is immediately recog­ shoot much abbreviated, arising from most nizable by the straight, not bent, stipe and of the mid- to distal leafaxils of fertile the generally larger, paler, fewer, more shoots, bearing a minute prophyll and a scattered inflorescences. Generally P. scan­ few 3-15 mm sequentially longer cata­ dens has flowering shoots arising at many phylls. Inflorescence 1-2. Peduncle rather of the leafaxils of long pendent fertile stout, 3-25 X 1.5-2.5 mm, erect to vari­ shoots, thus there are often numerous ously curved, green to brown-tinged; inflorescences. By contrast P. chinensis spathe 4-12 X 4-10 mm, ovate, concave, tends to produce flowering shoots at only margins in-rolled, base cordate, clasping the distal-most leafaxils of short spreading and slightly decurrent on the peduncle, fertile shoots, thus inflorescences are rather apex fornicate to recurved, acute to few. Pothos neoroxburghii also produces subacute with a rather stout mucro, inflorescences with a straight stipe but with greenish white to green, occasionally the inflorescences arising as in the manner P. C. BOYCE, 2009 23

of P. scandens. Inflorescence colours also much abbreviated to rarely rather elongat­ differ; purple spathe and cream fertile ed through reiteration, (foliage) leafless or, spadix in P. scandens, green spathe and occasionally, bearing developed but un­ white to yellow fertile spadix in P. chinen­ dersize foliage leaves. Inflorescence solitary sis. Field observations have detected a faint on each reiterating flowering shoot but but sweet odour from inflorescences of P. many such shoots arising sequentially; chinensis but no detectable odour from P. peduncle somewhat robust, strongly curv­ scandens. ing or straight, the inflorescence held erect, Sterile material of P. chinensis can be 2.5-6.5 cm X 1-4 mm, mid-green; spathe difficult to differentiate from P. scandens linear-triangular to narrowly oblong, 3.4- and P. neoroxbughii. Generally the petioles 6.7 X ca. 1 cm, base rounded, annulately of P. chinensis are less than half as long as inserted onto peduncle, apex acuminate, the lamina, and the lamina is twice or more slightly rough to smooth, pale brown as broad as the petiole, narrower and with a tinged reddish pink; spadix stipitate; stipe attenuate apex. However, variation is such 3-19 X 1-2 mm, terete;fertile portion 3.5- that intermediates are common. A feature 13.5 cm X .5-3 mm, very slender-cylindric, noted in P. chinensis, but yet to be recorded occasionally sterile at the tip, pale greyish for P. scandens and P. neoroxburghii, is the pink, older inflorescences blackish red. occurrence of f1agelliform foraging shoots. Flowers 3 X 2.1 X 1.6 mm diam., widely scattered, arranged in a lax spiral along the 2. Pothos curtisii Hook. f., Fl. Brit. Ind. spadix. Injructescence not observed. 6:554. 1893; Ridley, Fl. Mal. Penins. 5: 1279 (sub P. latifolius). 1925; Boyce, Ecology Blumea Boyce & Hay, 45: 186. 2000; Wet hill and lowland evergreen forest; Telopea 9(3): 547. 2001. Lectotype altitudes 60-600 m. selected by Boyce (2000): Malaysia, Perak, Larut, Kunstler ('Dr King's Distribution collector) 3887 (K!). Pothos peninsularis Alderw., Bull. Jard. Thailand, Peninsular Malaysia (type), Bot. Buitenzorg 3, 1: 381. 1920. Singapore, Sumatera. Pothos latifolius Hook. f., FI. Brit. Ind. 6: 554. 1893, nom. illeg., non Pothos Thai Distribution latifolius L. PENINSULAR. Narathiwat. Pothos kunstleri Hook. f., FI. Brit. Ind. 6: 554. 1893. Notes Pothos maingayi Hook. f., FI. Brit. Ind. 6: 554.1893. Pothos curtisii is the only species of the luzonensis group (see Boyce & Hay, 1998) Slender, heterophyllous, root-climbing occurring in Thailand. Fertile material is hemiepiphyte to 3 m. Stem (juvenile) ca. unmistakable by the slender spadix and 1.5 mm diam., terete to slightly angled in scattered flowers. Sterile specimens may be cross section, shingle-leaved; stem (ma­ confused with other species of the Allo­ ture) ca. 6 mm diam., terete in cross pothos supergroup, especially those occur­ section. Leaves scattered, spreading. Petiole ring in the same region of peninsular slender, canaliculate, rounded abaxially, 2- Thailand (e.g. P. kingii and P. leptosta­ 10.5 cm X 1-6 mm, base decurrent, apex chyus). Pothos leptostachyus and P. kingii prominently pulvinate; petiolar sheath dis­ have thinly chartaceous leaves, while P. tinct, prominent, erect, apically ligulate in curtisii has more coriaceous leaves. young growth, ligule later disintegrating, base amplexicaule or decurrent to almost 3. Pothos kingii Hook. f, Fl. Brit. Ind. free; lamina broadly to narrowly oblong 6:553. 1893; Ridley, FI. Mal. Penins. 5: elliptic, 8-26 X 1.6-9.5 cm. Flowering shoot 131. 1925; Boyce, Blumea 45: 189. 24 AROIDEANA, Vol. 32

2000; Boyce & Hay, Telopea 9(3): 515. Frequently, but not exclusively, associated 2001. Lectotype selected by Boyce with limestone; altitudes 50-450 m. (2000): Malaysia, Perak, Larut, Kuns­ tIer ('Dr King's Collector) 2723 (K!). Notes Pothos grandispathus Ridl., J. Straits Br. Unique by the deeply cucullate, softly Roy. Asiat. Soc. 41: 48. 1904 ('grand­ leathery, deep purple spathe, P. kingii is ispatha'). restricted to southern Peninsular Thailand Pothos ridleyanus Furtado, Gard. Bull. and a few localities in Peninsular Malaysia Sing. 8: 150. 1935. where it occurs in wet forest. Fertile speci­ Pothos ellipticus Ridl., J. Straits Br. Roy. mens are instantly recognizable but sterile Asiat. Soc. 41: 48. 1904, nom. illeg., material could be confused with vegetative­ non P. ellipticus Moon ex Miq. ly similar P. lorispathus (to which P. kingii is Moderate, slender, heterophyllous, root­ allopatric), and P. curtisii. The latter is climbing hemiepiphyte to 7 m. Stem (juve­ known from one locality in Peninsular nile) ca. 3 mm diam., terete in cross section, Thailand but is widespread and locally shingle-leaved; stem (mature) to 8 mm common in Peninsular Malaysia. diam., terete in cross section, leaves dense. Petiole slender, 4-12 cm X 2-2.5 mm;peti­ 4. Pothos teptostachyus Schott, Prodr. olar sheath extending to pulvinus, clasping Syst. Aroid.: 71. 1860; Ridley, FI. Mal. basally on juvenile and mature sterile shoots, Penins. 5: 130 (sub. P. lorispathus prominent and sheathing to 4/5 of its length ('Iorispatha'). 1925; Boyce, Blumea on fertile shoots; lamina ovate to elliptic or 45: 195 (sub. lorispatha). 2000; Boyce lanceolate, 5-25 X 2.5-9 cm, stiffly chartac­ & Hay, Telopea 9(3): 498. 2001. Type: eous, air drying dull green with the midrib Indonesia, S Kalimantan, Bangarmas­ pale yellow and prominently raised. Flow­ sin, Motley 1197 (K, holo). ering shoot elongated, leafy, arising from Pothos lorispathus Ridl., J. Straits Branch most of the mid- to distalleafaxils of fertile Roy. Asiat. Soc. 86: 310 1922 ('Ioris­ shoots. Inflorescence solitary; peduncle re­ patha'). flexed ca. 90° at the base, the inflorescence Moderate, robust, (heterophyllous?), held inverted beneath the shoot, 2-5 cm X root-climbing hemiepiphyte to 8 m. Stem 1.5-2.5 mm, stout, yellow to orange-brown; (mature) to 6 mm diam., terete in cross­ spathe ovate, deeply cucullate, 4-10 X 2.5- section; fertile shoots seldom branching, 6 cm, base slightly decurrent on the pedun­ stem of fertile shoot to 4 mm diam., dense­ cle, apex acute, deep purple inside and out, ly clothed with leaves; Leaves dense. Petiole softly-leathery and rather prominently net­ slender, 3-7 m long; petiolar sheath some­ veined; spadix sessile, cylindrical, 2.5-7 cm what prominent, extending to just below X 3-8 mm, deep purple-brown. Flowers ca. apical pulvinus, basally clasping, apically 1 mm diam .. Injructescence not observed. briefly auriculate to slightly ligulate; lami­ na oblong-elliptic, often falcate, unequal, Distribution occasionally quite strongly so, 10-34 X Thailand, Peninsular Malaysia. 2.5-10 cm, base rounded, apex acute to acuminate, very briefly tabulate, stiffly but Thai Distribution thinly chartaceous, air drying dull greenish. Flowering shoot arising from below the leaf PENINSULAR: Ranong, Surat Thani, Na­ axils of fertile shoots, abbreviated, usually khon Si Thammarat, Songkhla, Narathiwat. leafless but with I-several well-developed cataphylls, very occasionally with one or Ecology more fully developed but reduced leaves. Shady to open areas in wet primary Inflorescence solitary but flowering shoots evergreen forest, often on steep slopes. almost always reiterating and thus several P. C. BOYCE, 2009 25

inflorescences at varying degrees of devel­ 12 mm diam. Leaves dense. Petiole broadly opmental maturity often present; peduncle winged, oblong to obovate-oblong, 5- moderately stout 3-5 cm X 2-3 mm, erect 14 cm X 5-15 mm, with 4-5 secondary or curving and ultimately ascending and veins per side, base decurrent to clawed, the inflorescence held erect, dull green; apex truncate, rounded or auriculate; lam­ spathe lorate, 2.5-10 cm X 5-15 mm, ina ovate to elliptic or lanceolate, 3-18 X spreading, base auriculate, auricle margins 1.5-20.5 cm, with 2-4 intramarginal veins in-rolled, barely decurrent on the pedun­ per side, base rounded to acute, apex cle, apex obtuse, acuminate, mid-green; attenuate-mucronate to acute or attenuate, spadix stipitate; stipe 8-15 X ca. 2 mm, minutely tabulate, leathery. Flowering shoot slender, terete, lime green;Jertile portion 5- much abbreviated, arising from mostly the 6.5 cm X 3-4 mm, cylindrical to tapering middle to distal leafaxils of fertile shoots, slender-cylindrical, straight to slightly sometimes arising on older (foliage) leafless curved, base unequal, slightly cochleate, parts, bearing a minute prophyll and a few creamy-yellow. Flowers ca. 1.5 mm diam. 5-35 mm, sequentially longer cataphylls. Infructescence with numerous berries; fruit Inflorescence solitary; peduncle rather stout, 1-1.5 cm X 5-8 mm, obclavate to ellipsoid, 4-10 cm X 1.5-2 mm, erect, dull orange­ ripening deep scariet, with basal charta­ yellow; spathe ovate, 2.5-3 X 2-2.5 cm, flat ceous tepal remains. to convex, base cordate, clasping the pe­ duncle, apex slightly raised, acute to sub­ Ecology acute with a stout mucro, white, somewhat waxy; spadix stipitate; stipe terete in cross Damp to rather dry evergreen hill forest section, 2.5-4 cm X 2-2.5 mm, erect, on limestone; altitudes 50-100 m. straight, pale green; fertile portion ovoid­ clavate, 1.25-1.5 X 1-1.5 em, mid-yellow. Distribution Flowers ca. 1-2 mm diam. Infructescence Thailand, Peninsular Malaysia (type), with 1-5 berries; fruit obclavate to ovoid or Sumatera (Aceh), Borneo. ellipsoid, 1-1.75 X 1-1.4 cm, deep green ripening to scariet, epidermis of upper part Thai Distribution of ovary roughened in submature fruits, more or less smooth when ripe. Thailand. PENINSULAR: Yala. Ecology Notes Rainforest on rock along streams, moist Confusion with P. wallichii is possible, evergreen forest on moderate slopes. Fre­ although the stout (2-3 mm diam.) erect quently associated with limestone or gran­ peduncles and longer, lorate spathe readily ite; altitudes 50-300 m. distinguishes P. leptostachyus. Thai Distribution 5. Pothos macrocephalus Scort. ex PENINSULAR: Yala, Narathiat. Hook. f., FI. Brit. Ind. 6: 553. 1893; Ridley, Fl. Mal. Penins. 5: 128. 1925; Distribution Boyce, Blumea 45: 172. 2000; Boyce & Hay, Telopea 9(3): 476. 2001. Lecto­ Thailand, Peninsular Malaysia, Sumatera. type selected by Boyce (2000): Malay­ sia, Perak, Larut, Scortechini 116b Notes (CAL!, K!). A large distinctive hemiepiphyte which, Large, robust, homeophyllous, root­ for the area under review, has so far been climbing hemiepiphyte to 15 m. Stem (juve­ collected only in Yala and Narathiwat nile) to 8 mm diam., weakly angled or provinces of peninsular Thailand where its subterete in cross section; stem (mature) occurrence is sporadic. The large yellow- 26 AROlDEANA, Vol. 32

Plate 2. A: Pathos macmcephalus, th e most spectacular Pathos in Thail and; the large white and yell ow inflo rescences are immediately diagnosti c; B: Pathos neomxhul'ghii; long confused with P. scandens, but immediately separable by the straight, not re fl exed stipe; C: Pathos scandens, note the inflorescences in each of the leafaxil s and the re fl exed stipe; D-E: Pathos wallichii, the deflexed peduncle and reddish purple, white-stri ped spathe readily separate this from P. leptostachyus. lmages: A-B: © Forest He rbariu m; C: © David Scherberi ch; D: © Peter Boyce. Used with permission. P. C. BOYCE, 2009 27 and-white inflorescences are most similar in Infructescence with 1-5 berries; fruit ob­ appearance to those of P. gigantipes. How­ clavate, 1-1.75 X 1-1.5 cm, mid-green ever, the form of the mature and juvenile ripening to deep scarlet. leaves of these species is quite different. Sterile P. macrocephalus can be confused Thai Distribution with P. scandens although in the latter the SOUTH-WESTERN: Kanchanaburi, Phet­ petiole is generally shorter than the lamina and overall P. macrocephalus is a more chaburi. SOUTH-EASTERN: Prachin Buri, massive plant. Chachoengsao, Chon Buri, Rayong, Chant­ haburi, Trat. PENINSULAR: Surat Thani, 6. Pothos neoroxburghii P.e. Boyce, Phangnga, Phuket, Krabi, Nakhon Si Tham­ nom. nov. mmarat, Trang, Songkla, Pattani. Basionym: Pothos roxburghii de Vriese Distribution in F.A.W.Mique1, PI. Jungh.: 103 (851), non Schott, Aroideae: 22 (856); Pothos NW India through Burma as far south as longipedunculatus Engl., Pflanzenr., IV, Peninsular Thailand. 23B: 27(905), nom. illeg., non. Ridl., Bull. Misc. Inform. Kew 1925: 93 (925), nom. Ecology illeg. Lectotype selected here: Wallich Cat. On trees and rocks in primary and No. 4435D (K-WAL!). This is the only secondary wet lowland to hill evergreen physical specimen cited by de Vriese. The tropical forest; altitude 150-450 m. other syntype is: Wight leones III: 776, Large moderately robust, homeophyl­ Notes lous, root-climbing hemiepiphyte to 15 m. Stem to 15 mm diam., four-angled or de Vriese erected Pothos roxburghii slightly compressed-terete in cross section; seemingly unaware that the name was fertile shoot branching to ca. two orders, preoccupied for a Sumateran species now stem to 10 mm diam Leaves dense. Petiole known as Pothos junghuhnii de Vriese. 2-20 cm X 5-20 mm, broadly winged, Later uncritical synonymization of de Vri­ obovate-oblong to linear-oblong, with 2-3 ese's epithet into P. scandens, along with the secondary veins and numerous veinlets per illegitimacy of Engler's attempt at renaming side, base decurrent, apex truncate, round­ de Vriese's concept (as P. longipeduncula­ ed or auriculate; lamina 2-10 X 1-4 cm, tus) but based upon a new type has long ovate to elliptic or Ian ceolate with 2 obfuscated the status of plants that while intramarginal veins per side, base rounded resembling P. scandens, differ markedly in to acute, apex attenuate-mucronate, leath­ the larger inflorescences with the stipe not ery. Flowering shoot much abbreviated, reflexing. The new epithet is chosen to arising from most of the mid- to distal leaf continue in some way to reflect that Rox­ axils of fertile shoots, bearing a minute burgh, as so often, actually got the taxonomy prophyll and a few 3-10 mm, sequentially correct but simply failed to get the name longer, cataphylls. Inflorescence solitary; published in accordance with modem rules. peduncle slender, 3-15 X .5-2 mm, erect to spreading, green to purple-tinged; 7. Pothos scandens 1., Sp. Pl.: 698. 1753; spathe 4-10 X 4-10 mm, ovate, concave, Hook. f., FI. Brit. Ind. 6: 551. 1893; margins flate to slightly concave, base Ridley, Fl. Mal. Penins. 5: 127. 1925; short, apex rounded to acute with a tiny Gagnep. in Lecomte, FI. l'Indo-Chine, rather stout mucro, maroon; spadix long 6: 1083. 1942; Boyce, Blumea 45: 180. stipitate; stipe terete in cross section, 10-15 2000; Boyce & Hay, Te10pea 9(3): 461. X ca. 1 mm, erect, white; fertile portion 2001. Type: Herb. Hermann 4: 39, globose or ovoid to subclavate, 9-12 X 3.5- No. 329 (BM! lecto.; designated by 10 mm, white. Flowers ca. 1-2 mm diam. Suresh et. aI., Taxon, 32 (983) 127). 28 AROIDEANA, Vol. 32

0 Pothos hermaphroditus (Blanco) Merr., Sp. bent through 270 , greenish to maroon;fertile Blancoanae: 90. 19181. portion globose or ovoid to subclavate, 4-10 Batis hermaphrodita Blanco, FI. Filip. ed.l: X 3.5-10 mm, yellow-green to off-white. 791. 1837. Flowers ca. 1-2 mm diam. Injructescence Pothos angustifolius Presl, Epimel. Bot.: with 1-5 berries; fruit obclavate, 1-1.75 X 243.1849. 1-1. 5 cm, mid-green ripening to deep scarlet. Pothos chapelieri Schott, Aroideae: 22, t. 35. 1856-1857. Ecology Pothos exiguiflorns Schott, Aroideae: 21, t. On trees and rocks in primary and 41. 1856-1857. secondary wet to dry lowland to hill Pothos cognatus Schott, Aroideae: 22, t. 42. evergreen tropical to subtropical forest, 1856-1857. occasionally on sea cliffs, on a variety of Pothos scandens 1. var. cognatus (Schott) substrates including clay, limestone and Engl. in A. & c. DC., Monogr. Phan­ granite; altitude 0-2,100 m. erogam. 2: 84. 1879. Pothos zollingerianus Schott, Oesterr. Bot. Thai Distribution ~ochenbl. 5: 19. 1855 Pothos horsfieldii Miq., Fl. Ned. Ind. 3: 178. NORTHERN: Chiang Mai, Chiang Rai, 1856. Lampang, Nan, Phrae, Sukhothai, Phitsa­ nulok, Petchabun, Loei. NORTH-EASTERN: Pothos decipiens Schott, Bonplandia 7: 165. Nakhon Phanom. EASTERN: Chaiyaphum. 1859. SOUTH-~STERN: Kanchanaburi, Ph etch­ Pothos jallax Schott, Prodr. Syst. Aroid.: aburi. CENTRAL: Nakhon Nayok. SOUTH­ 560.1860. EASTERN: Prachin Buri, Chachoengsao, Moderate to rather large, slender to Chon Buri, Rayong, Chanthaburi, Trat. moderately robust, homeophyllous, root­ PENINSULAR: Surat Thani, Phangnga, Phu­ climbing hemiepiphyte to 6 m. Stem ket, Krabi, Nakhon Si Thammmarat, Trang, 10 mm diam., weakly four-angled or slight­ Songkla, Pattani. ly compressed-terete in cross section; fertile shoot often branching to four or more Distribution orders, stem to 5 mm diam Leaves dense. Madagascar through to India and Sri Petiole 2-14 cm X 5-20 mm, broadly Lanka (type) through Bangladesh to S~ winged, obovate-oblong to linear-oblong, China, south Indonesia through Peninsular with 2-3 secondary veins and numerous Malaysia to Borneo and the Philippines. veinlets per side, base decurrent, apex truncate, rounded or auriculate; lamina 2- Notes 10 X 1-4 cm, ovate to elliptiC or lanceolate with 2 intramarginal veins per side, base Pothosscandensis unmistakable in its typical rounded to acute, apex attenuate-mucro­ aspect, carrying rather small inflorescences on nate, leathery. Flowering shoot much abbre­ bent peduncles. However, the species is highly viated, arising from most of the mid- to distal variable. Some populations comprise high­ leafaxils of fertile shoots, bearing a minute climbing plants bearing tiny inflorescences prophyll and a few 3-10 mm, sequentially (Beusekom & Smitinand 2150, Geesink et al. longer, cataphylls. Inflorescence solitary; 7250, Larsen et at. 44267 and Smitinand 2959 peduncle slender, 3-15 X .5-2 mm, erect are representative of this element). to spreading, green to purple-tinged; spathe 4-8 X 4-7 mm, ovate, concave, margins s. Pothos waUichii Hook. f., Fl. Brit. Ind. variously in-rolled, base short or somewhat 6: 553. 1893; Ridley, FI. Mal. Penins. 5: long-clawed, apex rounded to acute with a 129 (sub. P. barberianus var. wall­ tiny rather stout mucro, greenish to maroon; ichii). 1925; Boyce & Hay, Telopea spadix stipitate; stipe terete in cross section, 9(3): 521. 2001. Type: ~allich Cat. 5-10 X ca. 1 mm, erect, the distal part erect to 4439 B (K-~AL!)) p. C. BOYCE, 2009 29

Pothos barberianus Schott var. wallichii and the slender (less than 1 mm diam.) (Hook.f.) Ridl., Mat. FI. Malay Penins. peduncle. It is similar to P. leptostachyus 3: 49. 1907 & Fl. Malay Penins. 5: 129. 1925. but readily separated by the much more slender arching, not erect, peduncles and Slender, (heterophyllous?), root-climb­ the generally shorter lanceolate spathe and ing hemiepiphyte. Stem ca. 6 mm diam. the glossy reddish purple with paler longi­ sub-terete. Leaves dense. Petiole slender, 6- tudinal streaks, not green, spathe limb. 9 cm long;petiolarsheath margins in-rolled and thus sheath not prominent, extending ACKNOWLEDGMENTS to just below pulvinus, basally clasping, apically briefly ligulate; lamina lanceolate This work was supported by the TRF/ to lanceolate-elliptic, 6-16 X 2-5 cm, base BIOTEC Special Program for Biodiversity acute to obtuse, apex acute to acuminate, Research and Training grant BRT R-15100S. very briefly apiculate; primary lateral veins arising at ca. SOO, very fine, stiffly but thinly UTERATURE CITED chartaceous, drying dull greenish. Flower­ ing shoot leafy, arising from the distal most Boyce, P. C. 2000. The genus Pothos (Ara­ portions of fertile shoots. Inflorescence ceae: Pothoideae: Potheae) of Thailand solitary. Peduncle very slender, 4-11 cm and Indochina. Blumea 45:147-204. X ca ..75 mm, arching, very rarely reflexed. --- & A. Hay. 1998. Current advances Spathe lanceolate, 4-5 X .5-1 cm, spread­ in the taxonomy of Pothos. In H. Li, et ing to weakly reflexing, base auriculate, al. (eds.), Acta Bot. Yunnan. Suppl. X, auricle margins in-rolled, barely decurrent Current advances in Araceae studies, on the peduncle, apex acute to acuminate, pp.43-47. dull reddish purple with paler longitudinal --- & ---. 2001. A taxonomic streaks. Spadix briefly stipitate; stipe ca. revision of Araceae tribe Potheae 2 mm long Jertile portion slender, cylindri­ (Pothos, Pothoidium andPedicellarum) cal, 5-7.5 cm X ca. 2 mm, straight to for Malesia, Australia and the tropical slightly curved, base unequal, slightly Western Pacific. Telopea 9(3):449-571. cochleate, creamy yellow. Flowers ca. Hay, A. 1995. The genus Pothos L. (Ara­ 1.2 mm diam. Infructescence with rather ceae-Potheae) in New Guinea, Solo­ few berries, these mostly carried on the mon Islands and Australia. Blumea 40: basal half of spadix. Fruit ellipsoid, 1- 397-419. 1.2 cm X 4-5 mm, with a prominent stigmatic remnant, ripening deep scarlet. Photo credits Plate 1 A & B. Copyright © Forest Ecology Herbarium, Bangkok. Used with permis­ sion. Evergreen forest; altitudes 100-200 m. Plate 1 C. Copyright © Dept. Plant Thai Distribution Sciences, Faculty of Research Science and Technology, Unimas. Used with permis­ PENINSULAR: Phatthalung. sion. Plate 1 D. Author's own image. Distribution Plate 2 A & B. Copyright © Forest Herbarium, Bangkok. Used with permis­ Thailand, Peninsular Malaysia, Java. sion. Plate 2 C. Copyright © 2004 by David Notes Scherberich. Used with permission. A new record for Thailand. Pothos wall­ Plate 2 D. Copyright © Forest Herbari­ ichii is immediately recognizable by the um, Bangkok. Used with permission. inflorescences pendent from leafy shoot tips Plate 2 E. Author's own image.