Disterigma micranthum A. C. Smith, Mem. New York Bot. Gard. 8(1): 52.  1952.  Type.  Ecuador.  El Oro:  Moromoro region, ca. 21 miles W of Portovelo, 1035-1280 m, 7 Oct 1944 (fl), Camp E-616 (holotype, NY, photo NY neg. 9892).

        Low shrub;  stem at base with many papyraceous, imbricate, lanceolate-oblong bracts to 6 mm long;  twigs laxly pilose with hairs 1 mm long, glabrate.  Leaves not crowded, 3 or 4 per centimeter, papyraceous when dry, narrowly elliptic, 8-10 x 3-4.5 mm, base and apex obtuse, margin flat, obscurely puberulent towards apex above, sparsely glandular-fimbriate beneath;  obscurely 3-5-plinerved, midrib and lateral nerves impressed above or slightly raised beneath;  petiole ca. 1 mm long, sparsely puberulent.  Inflorescence with flowers solitary, subsessile, glabrous;  floral bract suborbicular, to 1 mm long;  pedicel hardly 1 mm long;  bracteoles suborbicular, 2.5-3 mm long, scarious-margined, imbricate at base, surrounding calyx hypanthium and up to the middle of the lobes.  Flowers 4-merous, with calyx 2.5-3 mm long;  hypanthium obtusely-angled, ca. 1.5 mm long;  limb erect-spreading;  lobes deltate, subacute, ca. 1 x 1.5 mm;  sinuses acute;  corolla thinly carnose, urceolate, 3.5-4 mm long, white, the lobes oblong, subacute, ca. 1 mm long;  stamen 8, shorter than corolla, ca. 3 mm long;  filaments apparently slightly longer than anthers, ca. 1.6-2 mm long, villous distally with white hairs ca. 0.4 mm long;  anthers ca. 1.4-1.6 mm long;  thecae ca. 0.7-0.8 mm long, the base rounded;  tubules 2, distinct, equalling thecae, ca. 0.7-0.8 mm long, dehiscing through oval clefts ca. 0.5 mm long;  nectariferous disc annular-pulvinate;  style equal to corolla.  Berry not seen.

        Distribution.  Endemic to Ecuador and known from only two collections;  roadside banks in premontane rainforest to montane forest, at 1035-1600 m altitude.  Rare and endangered.