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 burkillii
Dunn
[sect.
Sphenanthera
]
Figs 16–18
Bulletin of Miscellaneous Information, Kew
1920: 110 (
Dunn 1920
)
. –
Type
:
India
, Arunachal-Pradesh, Janak river,
Nov. 1911
–
Mar. 1912
,
Burkill 37139
(lecto-: K000634633, here designated; isolecto-: B n.v.)
.
Citations in other publications
Burkill (1924: 288)
,
Tebbitt (2003b: 7)
, Morris (2006: 88)
,
Uddin (2007: 593)
,
Hughes (2008: 22)
,
Morris (2009b: 173)
,
Dash (2010: 32)
,
Saika
et al.
(2011: 357)
,
Baruah & Choudbury (2014: 41)
.
Other material
INDIA
:
Arunachal-Pradesh
: Abor Hills, Jauamukh,
Nov. 1911
–
Mar. 1912
,
Burkill 37121
(
CAL
n.v.); Bapu Mountain, Renging Camp,
Nov. 1911
–
Mar. 1912
,
Burkill 36720
(
K
); Bapu Mountain, Rotung,
Burkill 37706
(
CAL
n.v.); Bapu Mountain, Talauma,
Nov. 1911
–
Mar. 1912
,
Burkill 36910
(n.v.); Changlang, Namdapha Biosphere Reserve, Anamica Falls,
30 Nov. 2004
,
Amad Uddin 107934
(
ASSAM
); Dihang Valley,
12 Feb. 1928
,
Ward 7822
(
BM
,
K
); Igar Valley,
29 Nov. 1911
–
11 Mar. 1912
,
Burkill 16121
(n.v.); Janak river,
Nov. 1911
–
Mar. 1912
,
Burkill 37455
(
K
); Naharlagun,
Pal 70320
(
ARUN
n.v.); Papum Pare,
3 Apr. 2005
,
Morris AR2
(
CLEMS
n.v.); Pasighat,
10 Feb. 1928
,
Ward 7822
(
K
); Ponging,
Nov. 1911
–
Mar. 1912
,
Burkill 37375
(n.v.); Sangram to Panyu River,
Dash 32511
(
ARUN
n.v.); Serpo stream,
Nov. 1911
–
Mar. 1912
,
Burkill 36315
(n.v.); Shile River,
Burkill 37121
(n.v.); Subansiri District,
8 Apr. 2005
,
Morris 12
(
CLEMS
n.v.).
Assam
: Cacchar, Sonapur,
13 Jan. 2011
,
Himu Roy 143
(
GUBH
); Dhemaji, Silapathar, Poba Reserve Forest,
13 Jan. 2010
,
Ranjit Saika 300
(
GUBH
).
Description
Rhizomatous, dioecious herb,
20–40 cm
high. Rhizome: ca
10 mm
wide, glabrous, internodes
4–6 mm
long. Stipules: lanceolate, 5–17 ×
2–7 mm
, glabrous, persistent. Leaves: petiole 5–15(–25) cm long, glabrous; lamina ovate-lanceolate to ovate, basifixed, base cordate with lobes almost overlapping, (4–)10–20 × (3–)
6–9 cm
, asymmetric, upper surface variegated green and brown with a dark centre, glabrous or sparsely puberulent, underside variegated red and green, sparsely puberulent to glabrous, venation palmate-pinnate, midrib (3–)
8–18 cm
long; margin entire to shallow dentate, glabrous; apex shortly acuminate. Inflorescence: cymose, axillary, several; peduncle glabrous, branching twice, male primary
5–15 cm
, secondary
2–4 cm
, 2–6 flowers, female primary
4–6 cm
, 1(–2) flowers; bracts lanceolate, 6–20 ×
1–5 mm
, deciduous. Male flower: pedicel 13–25(–35) mm long, glabrous; tepals 4; outer tepals narrowly ovate, 10–30 ×
7–16 mm
, white to pink, glabrous, margin entire; inner tepals elliptic-obovate, 10–20 ×
3–7 mm
, white to pink, glabrous; androecium with 40 –70 stamens, symmetric; filaments
1–3 mm
long, unequal, free; anther elliptic-obovate,
2 mm
long, dehiscing through slits about half the length of the anther, not hooded, connective extended. Female flower: pedicel glabrous; bracteoles absent; tepals 4, similar to those of the male flower; ovary 4-locular, placentae bifid; capsule rhomboid, with 4 fleshy triangular wings/ridges; styles 4, forked once and twisted twice, deciduous. Fruit: on a stout pedicel, rhomboid; capsule oblong-ellipsoid, 20 ×
4–11 mm
, puberulous to glabrous, with 4 stubby wings or horns.
Fig. 16.
Map showing the location of
B. burkillii
Dunn
specimens.
Fig. 17.
Begonia burkillii
Dunn.
A
. Leaf
pattern.
B
. Male flowers. Photograph A courtesy of Aaron Matsumoto and photograph B courtesy of Earl I-Lan of plants in cultivation in private collections.
Fig. 18.
Illustration of
B. burkillii
Dunn.
A
. Habit
of plant.
B
. Style.
C
. Female flower.
D
. Stamen.
E
. Male flower.
F
. Male inflorescence. Drawn by Heather Raeburn. A–C from
Burkill 36720
; D from
Burkill 37455
; E–F from
Burkill 37139
; all K.
Distribution and phenology
Arunachal-Pradesh and Assam; also in
Myanmar
;
300–1100 m
. Flowering: February to March; fruiting: February to April.
Conservation status
Least Concern.
Begonia burkillii
has an EOO of
83,400 km
2
and an AOO of
72 km
2
, with a wide distribution through undisturbed forest in Arunachal-Pradesh and into Northern
Myanmar
.
Remarks
Specimens from the region lacked female flowers, which are described based on the protologue and photographs of cultivated plants. The leaf markings can vary in colour from red to purple-brown to almost black, but keep the same pattern (
Fig. 17
). This species is perhaps most similar to
B. handelii
in being rhizomatous and having 4-locular fruit, but that species has large rounded outer petals (not narrowly ovate), non-variegated leaves and fruit that is more pyramidal than rhomboid.
The lectotypification by
Saikia
et al.
(2011)
list two specimens (
Burkill 37706
and
37121
) and hence is not valid. Here
Burkill 37139
(K) is designated as the
lectotype
.