Geonoma sanmartinensis Henderson, 2011

Henderson, Andrew, 2011, A revision of Geonoma (Arecaceae), Phytotaxa 17, pp. 1-271 : 134

53. Geonoma sanmartinensis Henderson , sp. nov. (Appendix IV, Plate 57)

A speciebus affinibus crusta fructuum fibris epidermalibus brevibus numerosis apicem convergentibus differt.

Type: PERU. San Martín: Prov. Rioja, Dist. Naranjillo, sector San Augustin, Bosque de Protección de Alto Mayo, 5°48’S, 77°21’W, 1250 m, 13 November 1996, I. Sánchez Vega & M. Dillon 8658 (holotype NY!, isotypes CPUN n.v., F!).

Plants 1.2(0.5–2.0) m tall; stem branching no data; stem type no data; stem height no data; stem diameter no data; internode color no data; internode length no data. Leaves irregularly pinnate, not plicate, bases of blades running diagonally into the rachis; sheaths no data; petioles drying green or yellowish; rachis 38.6(35.8–41.0) cm long, 3.2(2.3–4.0) mm in diameter; veins raised and rectangular in cross-section adaxially; pinnae 4(3–7) per side of rachis; basal pinna 28.1(27.0–29.5) cm long, 4.3(0.9–6.8) cm wide, forming an angle of 46(30– 60)° with the rachis; apical pinna length no data, 12.3(9.2–15.0) cm wide, forming an angle of 27(22–32)° with the rachis. Inflorescences unbranched; prophylls and peduncular bracts ribbed with elongate, unbranched fibers, both bracts tubular, narrow, elongate, closely sheathing the peduncle, more or less persistent; prophylls 12.6(11.0–14.2) cm long, not short and asymmetrically apiculate, the surfaces not ridged, without unequally wide ridges; peduncular bracts 23.0(16.0–30.0) cm long, well-developed; inserted 1.1(0.8–1.4) cm above the prophyll; peduncles 63.5(63.0–64.0) cm long, 2.9(2.6–3.1) mm in diameter; rachillae 1, 21.1(18.5–24.7) cm long, 3.6(3.1–3.9) mm in diameter, the surfaces with 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 without a central notch before anthesis, not recurved after anthesis, hood-shaped at anthesis, sometimes splitting post-anthesis; 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 a scarcely raised rim; staminate and pistillate petals not emergent, not valvate throughout; staminate flowers deciduous after anthesis; stamens 6; thecae diverging at anthesis, inserted almost directly onto the filament apices, the connectives bifid but scarcely developed; anthers short and curled over at anthesis; non-fertilized pistillate flowers deciduous after anthesis; staminodial tubes crenulate or shallowly lobed at the apex, those of non-fertilized pistillate flowers not projecting and persistent after anthesis; fruits size no data, the bases without a prominent stipe, the apices not conical, the surfaces not splitting at maturity, without fibers emerging, bumpy from the numerous, subepidermal, tangential, short fibers present, these coming to a point at fruit apices; locular epidermis without operculum, smooth, without pores.

Distribution and habitat:— From 5°45’– 5°54’S and 77°21’– 77°45’W in Andean regions of Peru (San Martín) at 1525(1250–1850) m elevation in montane rainforest ( Fig. 36 ).

Taxonomic notes:— Geonoma sanmartinensis appears most similar to G. brongniartii . It differs in its fruits which are bumpy from the numerous, subepidermal, tangential, short fibers present.

Subspecific variation:— No trait varies within this species, nor is there any geographic disjunction.

Figures

FIGURE 36. Distribution maps of Geonoma pohliana subsp. wittigiana, G. poiteauana, G. sanmartinensis, and G. santanderensis.