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
15.
Geonoma deneversii
Henderson
,
sp. nov.
(Appendix IV, Plates 21–24)
A speciebus affinibus
staminibus plus quam sex differt.
Type:
PANAMA
.
Bocas del Toro
: E of Gualaca-Chiriquí Grande road,
10 mi.
N of continental divide,
1 mi.
along side road E,
8°55’N
82°05’W
,
100–500 m
,
19 January 1989
,
G. de Nevers, F. Almeda & G. McPherson 8823
(
holotype
NY!, isotypes BH!, K!, MO!).
Plant
height no data; stems
1.3 m
tall, solitary; internodes no data.
Leaves
20 per stem, irregularly pinnate, not plicate, bases of blades running diagonally into the rachis; sheaths no data; petioles drying green or yellowish; rachis
104.5 cm
long,
5.4 mm
in diameter; veins raised and rectangular in cross-section adaxially; pinnae 3 per side of rachis; basal pinna 87.0 cm long,
18.7 cm
wide, forming an angle of 31° with the rachis; apical pinna
25.5 cm
long,
27.5 cm
wide, forming an angle of 27° 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
35.5 cm
long, not short and asymmetrically apiculate, the surfaces not ridged, without unequally wide ridges; peduncular bracts 31.0 cm long, well-developed, inserted
2.7 cm
above the prophyll; peduncles
92.5 cm
long,
5.2 mm
in diameter; rachillae 1, 31.0 cm long,
9.9 mm
wide, 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 deciduous after anthesis; stamens more than 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; staminodial tubes projection no data;
fruits
no data.
Distribution and habitat:—
At
8°55’N
and
82°05’W
on the Caribbean slope in
Panama
(
Bocas del Toro
) at
250 m
elevation in lowland rainforest (
Fig. 15
).
Taxonomic notes:—
Geonoma deneversii
differs from similar species (
G. camana
,
G. chlamydostachys
,
G. chococola
) in its staminate flowers with more than six stamens. It is also the only species of this group to occur in Central America.
Subspecific variation:—
No trait varies within this species, and only one specimen is known.