Moderate, slender heterophyllous root-climbing liane to 7 m. Eocaul not observed; stem of juvenile shoot to 3 mm diam., terete in cross section, shingle-leaved; stem of mature sterile shoot to 8 mm diam., terete in cross section, mid-green, becoming brown with age, mostly densely clothed with leaves but stems eventually becoming naked, naked portions with prominent, 50 – 80 mm distant nodes; fertile shoot sparsely branched, stem to 5 mm diam., terete in cross section, densely clothed with leaves; foraging shoot subterete in cross section, to 1 mm diam., cataphylls falling swiftly and flagellum mostly naked with prominent nodes to 80 mm distant. Leaves when fresh bright to mid-green adaxially, slightly paler abaxially, stiffly chartaceous, air drying dull green with the midrib pale yellow and prominently raised; petiole 40 – 120 x 2 – 2.5 mm, slender, sheath extending to geniculum, clasping basally on juvenile and mature sterile shoots, prominent and sheathing to 4/5 of its length on fertile shoots; lamina 50 – 250 x 23 – 90 mm, ovate to elliptic or lanceolate with 3 intramarginal veins per side, the lowermost arising from the base, subsequent veins arising from the lower part of the midrib, outer intramarginal vein remaining very close and parallel to margin, the second and third progressively nearer to the midrib, all reaching the leaf tip base acute to rounded, apex attenuate-mucronate, acute or attenuate, minutely tubulate. Flowering shoot elongated, leafy, arising from most of the mid- to distal leaf axils of fertile shoots. Inflorescence solitary; peduncle 20 – 50 x 1.5 – 2.5 mm, stout, reflexed c. 90° at the base, the inflorescence held inverted beneath the shoot, yellow to orange-brown; spathe 40 – 100 x 25 – 60 mm, ovate, deeply cucullate, base slightly decurrent on the peduncle, apex acute, deep purple inside and out, softly-leathery and rather prominently net-veined; spadix sessile, 25 – 70 x 3 – 8 mm, cylindrical, deep purple-brown. Flowers c. 1 mm diam.; tepals 1 x 0.3 mm, oblong-cymbiform, deep purple-brown, apex fornicate, triangular, truncate, minutely three lobed; stamens 1 – 4 x c. 0.5 mm, filaments strap-shaped, thecae c. 0.2 mm diam, creamy-yellow; ovary 1 – 1.5 x 0.25 – 0.75 mm, compressed angular-ellipsoid, yellow-green to dirty white; stylar region truncate, centrally depressed; stigma prominently punctiform. Infructescence not observed.

Distribution — Thailand, Peninsular Malaysia.

Habitat & Ecology — Shady to open areas in wet primary evergreen forest, often on steep slopes. 50 – 450m.

Notes — Unique in the review area by the deeply cucullate, softly leathery, deep purple spathe, P. kingii is restricted to southern Peninsular Thailand and a few localities in Peninsular Malaysia where it occurs in wet forest. Fertile specimens are instantly recognizable but sterile material could be confused with vegetatively almost identical P. lorispathus (to which P. kingii is allopatric), and P. curtisii. The latter is known from one locality in Peninsular Thailand (see below) but is widespread and locally common in Peninsular Malaysia.
Pothos kingii belongs to a group of species characterized by thickened, often sharply deflexed long peduncles and often cucullate, somewhat leathery spathes; P. lancifolius Hook.f., P. barberianus Schott (Peninsular Malaysia, Borneo), P. hosei Rendle (Borneo), P. atropurpurescens M. Hotta (Borneo) belong here also.

Geographically representative selection of collections studied:
THAILAND. PEN64. Ranong: Hard Him Dam, 009° 20’N, 098° 25’E, 25 April 1974, Larsen & Larsen 33350 (fl.) (AAU). PEN65. Surat Thani: Khao Sok N.P., trail to Nam Tok Sib Aid Chan, 15 Sept. 1994, Boyce 962 (fl.) (BKF, K). PEN69. Nakhon Si Thammarat: Lansagah, Khao Luang N.P., Nam Tok Charone, 05° 50’N, 101° 50E, 14 April 1985, Ramari 35 (fl.) (BKF, L, PSU, UKM). PEN73. Songkhla: Rattapoom, Nam Tok Bori Pat, 16 Oct. 1984, Maxwell 84-338 (fl.) (BKF, GH, P, PSU, UKM). PEN76. Narathiwat: Sungei Kolok, Nikom Waeng, 26 Feb. 1974, Larsen & Larsen 32619 (fl.) (AAU, B, BKF, K, L, MO).