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
51j.
Geonoma pohliana
subsp.
weddelliana
(Wendland ex Drude) Henderson
,
comb. & stat. nov.
Basionym:
Geonoma weddelliana
Wendland ex
Drude (1882: 494)
. Type:
BRAZIL
.
Goiás
: between
Goiás
and Cuiaba, November-December 1844,
H. Weddell 2983
(
holotype
P!, isotype F!).
Geonoma schottiana
var.
palustris
Warming ex
Drude (1882: 493)
.
Geonoma warmingii
Hawkes (1952: 189)
. Type:
BRAZIL
.
Minas Gerais
: Lagoa Santa, no date,
E. Warming 1843
(
holotype
C
n.v
.,
holotype
image!).
Geonoma stenoschista
Burret (1930a: 233)
. Type:
BRAZIL
.
Minas Gerais
: between Rio Parauna and Serra do Cipó,
24 April 1892
,
A. Glaziou 20030
(
holotype
P!, isotype FI!).
Geonoma caudulata
Loesener in
Taubert (1896: 423)
. Type:
BRAZIL
.
Goiás
: Serra dos Viadeiros,
17 October 1894
,
E. Ule 226 (3150)
(
holotype
P!).
Geonoma plurinervia
Burret (1940b: 99)
. Type:
BRAZIL
.
Mato Grosso
: Capão Bonito, Campo Grande,
5 September 1936
,
W. Archer & A. Gehrt 74
(
holotype
B, destroyed, isotypes BH!, SP!,
US
!).
Geonoma telesana
Lorenzi (2010: 252)
. Type:
BRAZIL
.
Mato Grosso
: Mun. Matinha, Serra do Roncador,
11 December 2009
,
H. Lorenzi, J. Teles, K. Suares & T. Flores 6789
(
holotype
HPL
n.v.
, isotypes ESA
n.v.
, SP
n.v.
),
s
ynon. nov.
Leaves
pinnae 13(3–23) per side of rachis.
Inflorescences
rachillae 13(4–27), 2.0(1.0–3.4) mm in diameter, not hairy, not filiform and not or scarcely narrowed between the flower pits; proximal and distal lips drying darker brown than the rachillae; triads mostly decussately arranged.
Distribution and habitat:—
From 6°00’–
24°07’S
and 36°00’–
60°49’W
in the Cerrado region and adjacent areas of campo rupestre of
Brazil
and just reaching adjacent
Bolivia
and
Paraguay
at 1015(200– 1650) m elevation in wet places, usually in gallery forest (
Fig. 35
).
FIGURE 35
. Distribution maps of
Geonoma pohliana
subsp.
rubescens
,
G
.
pohliana
subsp.
trinervis
,
G
.
pohliana
subsp.
unanensis
,
and
G
.
pohliana
subsp.
weddelliana
.
There is geographical variation in this subspecies. Linear regression shows there are significant associations between elevation and eight leaf variables and four inflorescence variables. Squared multiple
R
for the regression of leaf number on elevation is 0.58, rachis width 0.10, number of pinnae 0.28, basal pinna length 0.18, basal pinna width 0.40, basal pinna angle 0.37, apical pinna width 0.31, apical pinna angle 0.19, peduncle width 0.15, number of rachillae 0.12, fruit length 0.33, and fruit diameter 0.45. In particular, number of pinnae increases and they become shorter and narrower with narrower angles with increasing elevation, giving a distinctive, small pinnate leaf. For inflorescences, peduncles become thinner, rachillae fewer, and fruits larger with increasing elevation. Specimens from higher elevations (
1000–1600 m
) in
Minas Gerais
(Serra do Cipó),
Goiás
(Chapada dos Veadeiros), and
Bahia
(Pico das Almas) have these kinds of leaves and inflorescences.
Specimens from the western and northern margins of the range have fewer, broader pinnae. Some specimens (e.g.,
Noblick 3209, Sant'Ana 311, Thomas 9251
) from the eastern margin of the range in
Bahia
occur near to the range of
subsp.
pohliana
, and there may be hybrids between these two subspecies in this area.
Some specimens (
Irwin 6276, 15633
) from the
Distrito Federal
near Brasília, have pinnae more like those of
subsp.
schottiana
. It is unclear if this subspecies is present in the
Distrito Federal
, or if these specimens are hybrids.