A revision of Geonoma (Arecaceae)
Author
Henderson, Andrew
text
Phytotaxa
2011
2011-02-18
17
1
271
journal article
24911
10.11646/phytotaxa.17.1
65962ba7-eec1-40e7-aed6-cef94e99ca39
1179-3163
3538362
7.
Geonoma calyptrogynoidea
Burret (1930a: 223)
. Type:
COLOMBIA
.
Antioquia
: La Mesa, no date,
W. Kalbreyer 1398
(
holotype
B, destroyed).
Neotype
(designated by de Nevers &
Grayum 1988
):
COLOMBIA
. Chocó: Zona de Urabá, Cerro del Cuchillo, sector Cuchillo Blanco,
10–20 m
,
15 October 1987
,
D. Cárdenas 668
(
neotype
MO!).
Plants
3.4(2.0–5.0) m tall; stems 2.9(1.5–4) m tall, 2.1(2.0–2.2) cm in diameter, solitary or clustered, canelike; internodes 2.9(2.6–3.1) cm long, yellowish and smooth.
Leaves
12
(
8–15) per stem, undivided or irregularly pinnate, not plicate, bases of blades running diagonally into the rachis; sheaths 30.2(19.5–43.5) cm long; petioles 35.5(19.0–50.0) cm long, drying green or yellowish; rachis 81.1(48.0–119.0) cm long, 6.8(4.4– 9.9) mm in diameter; veins raised and rectangular in cross-section adaxially; pinnae 3(1–8) per side of rachis; basal pinna 64.9(42.0–82.5) cm long, 22.0(11.5–40.5) cm wide, forming an angle of 27(15–42)° with the rachis; apical pinna 37.1(17.5–48.0) cm long, 23.2(14.3–33.0) cm wide, forming a 29(22–35)° angle with the rachis.
Inflorescences
branched 1 order; prophylls and peduncular bracts not ribbed with elongate, unbranched fibers, flattened, deciduous or persistent; prophylls 22.1(16.0–28.2) cm long, not short and asymmetrically apiculate, the surfaces ridged with close, equal, parallel, non-dividing ridges, scarcely tomentose between the ridges, without unequally wide ridges; peduncular bracts 25.3(21.5–30.0) cm, well-developed, inserted 2.9(1.4–4.8) cm above the prophyll; peduncles 45.4(32.0–60.4) cm long, 7.3(4.5–10.3) mm in diameter; rachillae 5(3–9), 21.7(14.5–34.0) cm long, 6.1(4.5–8.3) 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 without a central notch before anthesis, 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 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 persistent after anthesis; staminodial tubes crenulate at the apex, those of non-fertilized flowers projecting and persistent after anthesis;
fruits
13.2(11.8–15.5) mm long, 10.0(8.3–11.2) mm in diameter, the bases with a prominent, asymmetric stipe, the apices not conical, the surfaces not splitting at maturity, with fibers emerging, not bumpy, not apiculate; locular epidermis with operculum, smooth, with pores.
Distribution and habitat:—
From
8°20’N–
1°02’ and 74°11’–
78°42’W
in eastern
Panama
, the Pacific coast of
Colombia
and
Ecuador
, and the
Magdalena
and
Cauca
valleys in
Colombia
, at 212(15–550) m elevation in lowland rainforest (
Fig. 11
).
Taxonomic notes:—
This species was included as a synonym of
Geonoma congesta
by
Henderson
et al.
(1995)
, but this placement was disputed by
de Nevers & Grayum (1998)
. While closely related,
G. calyptrogynoidea
differs from
G. congesta
by its proximal lips of flower pits without a central notch before anthesis.
Subspecific variation:—
Two traits (stem branching, leaf division) vary within this species. There is evidence of geographic discontinuity and the species occurs in two areas—eastern
Panama
and the Pacific coast of
Colombia
and
Ecuador
(the gap in southern
Colombia
is likely to be an artifact of insufficient collecting), and the
Magdalena
and
Cauca
valleys in
Colombia
. The
Magdalena
and
Cauca
population has inflorescences with more, longer rachillae, but there are too few specimens to test for differences between the two areas.