A revision and one new species of Begonia L. (Begoniaceae, Cucurbitales) in Northeast India
Author
Camfield, Rebecca
Author
Hughes, Mark
text
European Journal of Taxonomy
2018
2018-01-19
396
1
116
journal article
22365
10.5852/ejt.2018.396
2b95a851-e1bf-4bdd-9cce-441ddc4135d2
3787049
Begonia adscendens
C.B.Clarke
[sect.
Diploclinium
]
Figs 8–9
Journal of the Linnean Society, Botany
25: 26 (
Clarke 1890
)
. –
Type
:
India
,
Nagaland
, Naga Hills, Jakpho,
25 Oct. 1885
,
Clarke 41240
(lecto-: K000634623, here designated; isolecto-: CAL n.v.).
Begonia obversa auct
. non
C.B.Clarke: Chauhan in
Flora of
Manipur
:
425 (
Chauhan 2000
)
.
Citations in other publications
As
B. adscendens
:
Uddin (2007: 591)
,
Hughes (2008: 3)
,
Uddin
et al.
(2008: 53)
.
Other material
INDIA
:
Manipur
: Esii Hill,
1 Sep. 2006
,
Mao & Gogoi 109408
(
ASSAM
n.v.).
Nagaland
: Naga Hills, Jakpho,
Clarke 41247
(
CAL
n.v.).
Description
Tuberous, monoecious herb,
30–50 cm
high. Stipules: ovate, 2 ×
1–2 mm
, glabrous, caduceus. Leaves: petiole
5–15 cm
long, glabrous; lamina ovate to broadly ovate, basifixed, base cordate with lobes not overlapping, 4–16 ×
2–22 cm
, slightly asymmetric, upper surface green, glabrous, underside pale green or pale green with red markings, puberulous on veins mostly, venation palmate; midrib
3.5–13 cm
long; margin toothed at the end of the veins with smaller teeth between, with sparse hairs; apex shortly acuminate. Inflorescence: cymose, terminal, few; peduncle glabrous, branching 1–2 times, primary
10–18 cm
long, secondary
1–4 cm
long, with 2–
4 female
and 2–
6 male
flowers; bracts not seen. Male flower: pedicel
8–13 mm
long, glabrous; tepals 4; outer tepals orbicular to ovate, 10–18 × (5–)
9–12 mm
, white to pink, sparsely pale puberulous on reverse, near the base, margin entire; inner tepals narrowly elliptic, 5–7 ×
1–3 mm
, white to pink, glabrous; androecium with 16–20 stamens, asymmetric; filaments
1–1.5 mm
long, unequal, fused at base into a short column; anther oblong elliptic,
1 mm
long, slightly hooded, connective not extended. Female flower: pedicel
8–18 mm
long, glabrous; bracteoles absent; tepals 4–5, unequal, ovate, outer tepals, 8–15 ×
5–7 mm
, white tinted pink, sparsely puberulent on reverse, margin entire, inner tepals as in male; ovary 3-locular, placentae bifid; capsule globose-ellipsoid, glabrous, with one long triangular wing and two short triangular wings; styles 3, convoluted with slightly twisted ends, persistent. Fruit pendulous; capsule globose-ellipsoid 6–10 ×
4–6 mm
, glabrous; wings extending along the pedicel slightly, unequal; longest wing rounded oblong, 26–28 ×
7–8 mm
; shortest wings triangular, 3 ×
1–3 mm
.
Distribution and phenology
Manipur and Nagaland; also in
Myanmar
and
Laos
;
2400–2600 m
. Flowering: September to October; fruiting: October.
Conservation status
Least Concern. Current data for
B. adscendens
gives an EOO of
113,895 km
2
and an AOO of
32 km
2
. This sample size is low, but the specimens are widespread. The data would suggest this species is vulnerable but due to the distribution and supply of suitable habitat this species is classed as least concern. This species is found throughout the
Arakan
mountains and into the mountains of Northern
Myanmar
, both of which have extensive areas of suitable habitat.
Fig. 8.
Map showing the location of
B. adscendens
C.B.Clarke
specimens.
Fig. 9.
Illustration of
B. adscendens
C.B.Clarke
by J. Allen (
Clarke 1890
). a. Dissected fruit capsule. b. Fruit cross-section diagram. Image courtesy of RBGE library and Lynsey Wilson.
Remarks
This species is similar to
B. labordei
which differs in having hairy leaves and dark purple hairs on the exterior of the male flowers that are visible without a microscope; the hairs are pale and near the base of the tepals in
B. adscendens
. The two species also differ in fruit wing shape; the longest wing curves adaxially on
B. labordei
but on
B. adscendens
it reaches up past the apex of the fruit capsule. This species is one of the highest altitude
Begonia
in Northeast
India
.