Geonoma rivalis Kalbreyer & Burret, Bot. Jahrb. Syst. 63: 241. 1930. Type. COLOMBIA. Antioquia: Coco, 700-900 m, 18 Feb 1880, W. Kalbreyer 1427 (holotype: B, destroyed). COLOMBIA. Antioquia: Municipio de San Luis, Río Samana on the Medellín-Bogotá road, 6°00´N, 74°50´W, 700-780 m, 23 Jun 1987, R. Callejas, A. Arbelaez, H. Correa & J. Betancur 4098 (neotype, here designated, NY!; isoneotypes: COL, MO!).

Plant height 1.7(1.2-2.0) m, CV 0.3, n = 3; stems solitary; stem diameter 4.8(4.0-5.6) cm, CV 0.2, n = 2; number of leaves per stem 14(12-16), CV 0.2, n = 2. Leaves regularly pinnate with narrowly linear, 1-veined pinnae; petiole length 31.5(9.0-54.0) cm, CV 1.0, n = 2; rachis length 69.5(62.5-76.5) cm, CV 0.1, n = 2; rachis width 4.8(3.8-5.8) mm, CV 0.2, n = 4; number of leaf divisions per side of rachis 31(27-36), CV 0.1, n = 4; basal angle of pinna divergence 28(24-35)°, CV 0.2, n = 4; basal pinna width 0.4(0.2-0.8) cm, CV 0.6, n = 5; apical angle of pinna divergence 21(14-27)° CV 0.3, n = 5; apical pinna width 1.2(0.4-1.8) cm, CV 0.4, n = 6. Inflorescences horizontal or pendulous and infrafoliar or less often interfoliar; prophyll length 14.5(13.5-15.6) cm, CV 0.1, n = 3; peduncular bract length 12.1 (10.5-13.7) cm, CV 0.2, n = 2; distance between bract scars 2.6(1.0-4.5) cm, CV 0.7, n = 3; peduncle length 12.4(7.0-20.0) cm, CV 0.5, n = 5; peduncle width 6.1(2.5-9.7) mm, CV 0.8, n = 2; orders of inflorescence branching 2-3, n = 4; rachilla length 13.7(9.2-17.0), CV 0.2, n = 8; rachilla width 1.8(1.5-2.3) mm, CV 0.2, n = 8; number of rachillae no data; rachillae tending to collapse between the pits on drying, the pits longer than wide; pistillate flowers mostly persistent after anthesis, the pits not becoming narrowed; proximal lip of pit not hairy internally, or only along the margins; rachillae hairs absent; fruit diameter 3.6 mm, n = 1; fruit length 4.8 mm, n = 1.

Distribution. From 5°50´-7°22´N and 74°45´-75°05´W at a mean elevation of 548 (150-900) m on the eastern slopes of the Central Cordillera in Colombia (map). There is geographic discontinuity but too few specimens to test for differences amongst areas.