37b. Geonoma maxima subsp. ambigua (Spruce) Henderson, comb. & stat. nov.

Basionym: Geonoma ambigua Spruce (1871: 111) . Geonoma maxima var. ambigua (Spruce) Henderson (1995: 278) . Type: GUYANA. Without locality, no date, C. Appun 566 (holotype K!).

Geonoma schomburgkiana Spruce (1871: 111) . Type: GUYANA. Without locality, 1837, R. Schomburgk 705 (holotype K!, excluding leaf).

Leaves irregularly pinnate (sometimes with 1-veined pinnae present), not plicate; rachis 40.0(13.0–59.0) cm long; pinnae 4(2–12) per side of rachis; basal pinna 7.5(1.9–22.0) cm wide, forming an angle of 40(20–60)° with the rachis. Inflorescences rachillae 18(5–39).

Distribution and habitat:— From 1°55’– 8°34’N and 57°52’– 62°55’W in Guyana and adjacent Venezuela and Brazil at 337(35–900) m elevation in lowland rainforest in a variety of habitats, including flooded and non-flooded areas (Fig. 25).

A specimen from Guyana (McDowell 4479) has more pinnae than others and approaches subsp. maxima in its leaf morphology. Although subsp. ambigua has fewer pinnae per side of the rachis than subsp. m axima, it usually has a few, 1-veined pinnae present.