Geonoma pinnatifrons subsp. pinnatifrons

Henderson, Andrew, 2011, A revision of Geonoma (Arecaceae), Phytotaxa 17, pp. 1-271 : 119

49a. Geonoma pinnatifrons subsp. pinnatifrons

Geonoma pulchra Engel (1865: 686) . Type: COLOMBIA. Norte de Santander: Ocaña, 2000–3000 m, August 1859, F.

Engel s. n. (holotype B, destroyed, isotype LE!).

Leaf pinnae 11(3–39) per side of rachis. Inflorescences peduncular bracts inserted 2.8(0.6–6.5) cm above the prophyll; peduncles 25.2(11.0–41.0) cm long, 7.5(3.6–12.9) mm in diameter; rachillae 15.2(8.6–25.7) cm long, 2.2(1.1–3.4) mm in diameter fruits 5.0(3.6–6.3) mm in diameter.

Distribution and habitat:— From 2°43’S– 11°10’N and 63°25’– 78°12’W in Venezuela, Colombia, and Ecuador, and just reaching eastern Panama, at 898(30–1900) m elevation in lowland to montane rainforest ( Fig. 31 ).

There is geographical variation in this subspecies. Regression shows there are significant (P <0.05) associations between elevation and three leaf and three inflorescence variables. Squared multiple R for the regression of petioles on elevation is 0.57, basal pinna length 0.27, basal pinna width 0.28, prophyll length 0.39, rachilla length 0.27, and fruit length 0.23. Petioles become shorter, basal pinna shorter and narrower, prophyll and rachillae shorter, and fruits longer with increasing elevation.

Clustered-stemmed plants occur commonly in this subspecies in Venezuela, and these occur at a higher mean elevation (1170 m) than those with solitary stems (677 m).

Figures

FIGURE 31. Distribution maps of Geonoma pinnatifrons subsp. pinnatifrons, G. pinnatifrons subsp. binervia, G. pinnatifrons subsp. martinicensis, and G. pinnatifrons subsp. membranacea.