Geonoma chococola Wessels Boer 1968
Creators: name: Henderson, Andrew
Publisher: name: Zenodo
Year: 2011
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Liliopsida
Arecales
Arecaceae
Geonoma
Geonoma chococola

description: 10. Geonoma chococola Wessels Boer (1968: 103). Type: COLOMBIA. Valle del Cauca: Buenaventura, 6 May 1926, O. Cook 84 (holotype US!).
Plants 2.8(1.5–4.0) m tall; stems 1.9(1.0–3.0) m tall, 3.5 cm in diameter, solitary or clustered, cane-like; internodes 3.7 cm long, yellowish and smooth. Leaves 11(7–21) per stem, undivided or irregularly pinnate, not plicate, bases of blades running diagonally into the rachis; sheaths 16.5(8.0–23.0) cm long; petioles 37.9(15.3–61.0) cm long, drying green or yellowish; rachis 111.7(80.0–137.0) cm long, 7.6(4.6–12.5) mm in diameter; veins raised and rectangular in cross-section adaxially; pinnae 3(1–7) per side of rachis; basal pinna 48.5(30.0–80.0) cm long, 13.2(4.5–43.5) cm wide, forming an angle of 27(16–38)° with the rachis; apical pinna 30.1(21.7–40.5) cm long, 26.5(20.5–35.0) cm wide, forming an angle of 28(20–40)° with the rachis. Inflorescences unbranched or branched 1 order; prophylls and peduncular bracts ribbed with elongate, unbranched fibers, both bracts tubular, narrow, elongate, closely sheathing the peduncle, more or less persistent; prophylls 35.0(23.7–49.5) cm long, not short and asymmetrically apiculate, the surfaces not ridged, without unequally wide ridges; peduncular bracts 60.8(38.5–83.0) cm long, well-developed, inserted 2.2(1.5– 3.0) cm above prophyll; peduncles 86.3(46.0–143.0) cm long, 6.4(3.9–8.6) mm in diameter; rachillae 1(1–4), 27.8(16.5–47.0) cm long, 10.1(5.8–15.2) mm in diameter, the surfaces without spiky, fibrous projections or ridges, drying brown or yellow-brown, without short, transverse ridges, not filiform and not narrowed between the flower pits; flower pits spirally arranged, glabrous internally; proximal lips with a central notch before anthesis, often the two sides of the notch overlapping, not recurved after anthesis, not hood-shaped; proximal and distal lips drying the same color as the rachillae, not joined to form a raised cupule, the proximal lip margins overlapping the distal lip margins; distal lips well-developed; staminate and pistillate petals not emergent, not valvate throughout; staminate flowers persistent after anthesis; stamens 6; thecae diverging at anthesis, inserted directly onto the apiculate filament apices; anthers not short and curled at anthesis, usually elongate, spiraled and twisted or sometimes remaining straight; non-fertilized pistillate flowers deciduous after anthesis; staminodial tubes lobed at the apex, the lobes spreading at anthesis, acuminate, those of nonfertilized flowers not projecting and persistent after anthesis; fruits 18.9(14.8–24.9) mm long, 15.7(11.3–17.8) mm in diameter, the bases without a prominent stipe, the apices not conical, the surfaces splitting deeply and longitudinally at maturity to reveal mesocarp with dense layer of radial fibers, with fibers emerging, not bumpy, not apiculate; locular epidermis with operculum, smooth, with pores.
Taxonomic notes:— Geonoma chococola was said by Henderson et al. (1995) to have 12 stamens, but this appears to be a mistake. All eight specimens examined with staminate flowers have 6 stamens. In the following treatment, G. awaensis is recognized as a subspecies of G. chococola; it is not recognized at the species level because it shares the same character state combinations as G. chococola.
Subspecific variation:— Three traits vary within this species (stem branching, leaf division, inflorescence branching). There is geographic discontinuity and specimens occur in two separate areas. Based on one trait distribution (inflorescence branching) and geography, two subgroups can be recognized and these are treated as subspecies (subspp. chococola, awaensis). There are too many missing data for most variables for analysis, but subsp. chococola has significantly longer and wider rachillae (t -test, P <0.05).
Key to the subspecies of G. chococola
1 Inflorescences unbranched................................................................................................................. subsp. chococola
- Inflorescences branched with 2–4 rachillae.......................................................................................... subsp. awaensis
description: Published as part of Henderson, Andrew, 2011, A revision of Geonoma (Arecaceae), pp. 1-271 in Phytotaxa 17 on pages 48-49, DOI: 10.11646/phytotaxa.17.1, http://zenodo.org/record/3538362