Psammisia pterocalyx Luteyn, Opera Botanica 92: 117, fig. 5.  1987.  Type.   Colombia. Chocó:  North ridge of Alto de Buey, ESW of El Valle, 500-1150 m, premontane wet forest, 8 Aug 1976 (fl), Gentry & Fallen 17391 (holotype, COL;  isotype, NY).  Image:  Line-drawing.

        "Epiphytic vine", glabrous throughout;  mature stems terete, striate;  bark grayish-brown when dry;  young twigs complanate, minutely striate, yellowish-brown when dry.  Leaves coriaceous, opposite, lance-elliptic, 13-16 x 4-6.5 cm, basally rounded and subcordate, apically acuminate;  pinnately-nerved with 3-5 lateral nerves, midrib slightly elevated for 1/2 to 3/4 proximal length and then impressed distally above, raised beneath, lateral nerves impressed above and raised beneath, veinlets impressed above and raised but inconspicuous beneath;  petiole subterete, flattened abaxially, rugose, 2-4 mm long.  Inflorescences 1 or 2, arising from raised nodes just above the axils of fallen leaves, seemingly each up to 2-4-flowered;  rachis angled, to 0.8 cm long;  floral bracts minute, persistent, broadly ovate, acuminate, ca. 0.5 x 2 mm, apically glandular-fimbriate;  pedicels opposite and decussate, subterete, striate, 19-20 mm long;  bracteoles near base, ovate, ca. 1 mm long, marginally glandular-fimbriate.  Flowers with calyx red when fresh, 8-12 mm long, broadly winged its entire length, the wings 3 mm broad, alternating with the lobes and produced beyond them;  hypanthium ca. 5-7 mm long, cylindric, articulate with the pedicel;  limb cylindric-campanulate, 3-5 mm long including the lobes;  lobes apiculate, less than 0.5 mm long;  sinuses broadly flattened;  corolla tubular, ca. 34-36 mm long, "yellow with red tips" when fresh, the lobes ca. 2.5 mm long;  stamens 10, equal, ca. 15 mm long;  filaments distinct, weakly tufted-pilose dorsally, ca. 3-4 mm long;  connectives alternately thin and obscure or thick conspicuous, the latter prolonged as a shoulder;  anthers 12 mm long including the rigid tubules;  thecae 9 mm long, basally prognathous;  style to 42 mm long.  Fruit not seen.

        Distribution.  Endemic to Colombia (Chocó), where it is known only from the type collection.  Rare and endangered.