A new species of fleshy-fruited Begonia (Begoniaceae) from the Masoala Peninsula, MadagascarAuthorHughes, MarktextAdansonia201132011-06-303318185http://dx.doi.org/10.5252/a2011n1a4journal article10.5252/a2011n1a41639-47984599214Begonia masoalaensis
M.Hughes
,
sp. nov.
(
Fig. 1
)
Begonia masoalaensissp. nov.tuberis praesentia et foliis maculatis marginibus sinuosis a ceteris speciebus madagascariensibus et insulis affinibus cum fructu carnoso (B. comorensis
,
B. humbertii
,
B. oxylobaetB. salaziensis) differt
.
TYPUS
. —
Madagascar
.
Antsiranana
,
Masoala Peninsula
, forest surrounding research station at
Anronabe
on west coast,
15°39’30”S
,
49°57’30”E
,
0-600 m
,
19.II.1992
,
Zjhra
&
Hutcheon
175
(holo-,
MO; iso-, E).
DESCRIPTION
Tuberous repent herb to
10-20 cm
high. Tuber
c
. 2 ×
0.8 cm
when dry, elliptic, narrowing at the ends, circular in cross section. Stem to
c
.
8 cm
long, with many adventitious roots, hairy, more so towards the apex, hairs simple,
c
.
1.5 mm
long. Stipules persistent,
c
.
6 mm
long with hairs on the keel. Leaves
2-3 in
number; petiole
1-5 cm
long, densely covered in
1.5 mm
long simple hairs; lamina green with an even covering of tiny white or red dots, 8-22 ×
5-11 cm
in total,
7-16 cm
long from point of petiole attachment to tip, ovate, markedly asymmetric, cordate at base, venation palmatepinnate; margin sinuate, denticulate with a fringe of hairs
c
.
0.25 mm
long. Inflorescence terminal, spicate, bisexual, usually with two main axes, each terminating in a female flower, primary peduncle
c
.
3 cm
long; bracts persistent,
2-3 mm
long, glabrous; male flowers with 4 white tepals, outer sub orbicular,
c
.
5 mm
in diameter, inner linearelliptic to
c
.
5 mm
long; stamens
c
. 15, filaments
1.5 mm
long, free, anthers just over
1 mm
long, elliptic-oblong, not hooded, dehiscing through slits running the entire length of the anther; female flowers with 4 white tepals, similar in shape and dimensions to those in the male flowers, ovary cigar-shaped,
c
.
1 cm
long on flowering, stigmas 3, stigmatic surface in a simple U-shaped band. Fruit fleshy, cigar-shaped,
c
.
3 cm
long,
3 mm
wide when dried, glabrous, indehiscent; placentation axile, placentae bifid. Seeds barrel-shaped, size at maturity not known, collar cells less than ⅓ the length of the seed.
FIG. 1. —
A,Begonia masoalaensis
M. Hughes
,
sp. nov.
, bearing two female flowers with the scars of the shed male portion of the inflorescence below:
B
, cross section of ovary;
C
, male flower. Scale bars: A, C, 1 cm; B, 5 mm.
N
National park Vegetation type:
FIG. 2. — Map of the Masoala Peninsula in Madagascar,showing the National park and the location of
Begonia masoalensis
M.Hughes
,
sp. nov.
(
Þ
). Vegetation data derived from
Du Puy & Moat (1997)
.
DIAGNOSTIC CHARACTERSBegonia masoalaensis
differs from other Malagasy and neighbouring islands species with fleshy fruit (
B. comorensis
,
B. humbertii
,
B. oxyloba
and
B. salaziensis
) in having a tuber and spotted leaves with sinuate edges.
CONSERVATION ASSESSMENTThe Masoala National park
is currently well protected (
C
. Kremen pers. com.).
However
, this species is currently known only from the
type
locality, which is at a low altitude just within the border of the reserve, and hence is considered to be Vulner- able (
VUD2
) (
Standards and Petitions Working Group 2006
)
.