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REINWARDTIA
Vol 14, No 1, pp: 19 − 26
19
east of Sulawesi, is poorly known. Since the de-
scription of B. holosericea (Teijsm. & Binn.)
Teijsm. & Binn. ca. 150 years ago, only one other
endemic Moluccan Begonia species has been de-
INTRODUCTION
The Begonia flora of the Indonesian Islands
group of the Moluccas, located west of Papua and
STUDIES ON BEGONIA (BEGONIACEAE) OF THE MOLUCCA ISLANDS I:
TWO NEW SPECIES FROM HALMAHERA, INDONESIA, AND AN
UPDATED DESCRIPTION OF BEGONIA HOLOSERICEA
Received January 10, 2014; accepted March 06, 2014
WISNU H. ARDI
Bogor Botanic Gardens, Jl. Ir. H. Juanda No. 13, Bogor, Indonesia, E-mail: wisn001@lipi.go.id
YAYAN W. C. KUSUMA
Bogor Botanic Gardens, Jl. Ir. H. Juanda No. 13, Bogor, Indonesia, E-mail: yayanwahyu@gmail.com
CARL E. LEWIS
Fairchild Tropical Botanic Garden, 10901 Old Cutler Road, Miami, FL, 33156, USA. E-mail:
clewis@fairchildgarden.org
ROSNIATI A. RISNA
Bogor Botanic Gardens, Jl. Ir. H. Juanda No. 13, Bogor, Indonesia, E-mail: rosniatirisna@yahoo.com
HARRY WIRIADINATA
Herbarium Bogoriense, Botany Division, Research Center for Biology-LIPI, Cibinong Science Center, Jl. Raya
Bogor−Jakarta Km. 46, Cibinong 16911, Bogor, Indonesia. E-mail: harry_wiria@yahoo.com
MELISSA E. ABDO
Florida International University, Dept. of Biological Sciences, 11200 SW 8th St., Miami, FL, 33199, USA. E-mail: mab-
do002@gmail.com
DANIEL C. THOMAS
Naturalis Biodiversity Center, Leiden, P. O. Box 9514, 2300 RA Leiden, the Netherlands. E-mail:
daniel.thomas@naturalis.nl
ABSTRACT
ARDI, W. H., KUSUMA, Y. W. C., LEWIS, C. E., RISNA, R. A., WIRIADINATA, H., ABDO, M. & THOMAS, D.
C. Studies on Begonia (Begoniaceae) of the Molucca Islands I: Two new species from Halmahera, Indonesia, and an
updated description of Begonia holosericea. Reinwardtia 14(1): 19 – 26. ― Two new species of Begonia, Begonia
holosericeoides Ardi & D.C. Thomas and B. aketajawensis Ardi & D.C. Thomas, are described from Aketajawe Lolo-
bata National Park, Halmahera, Indonesia. The two species belong to Begonia section Petermannia. Begonia holos-
ericea, previously only tentatively assigned to a section, is here assigned to section Petermannia based on the examina-
tion of newly available material. Additionally, a revised description and an illustration are provided. A key to the
Moluccan species of Begonia is presented.
Key words: Begonia, new species, Halmahera.
ABSTRAK
ARDI, W. H., KUSUMA, Y. W., LEWIS, C. E., RISNA, R. A., WIRIADINATA, H., ABDO, M. & THOMAS, D. C.
Study Begonia (Begoniaceae) Kepulauan Maluku I: Dua jenis baru dari Halmahera, Indonesia, dan pertelaan terbaru
Begonia holosericea. Reinwardtia 14(1): 19 – 26. ― Dua jenis baru Begonia, Begonia holosericeoides Ardi & D.C.
Thomas and B. aketajawensis Ardi & D.C. Thomas dipertelakan dari Taman Nasional Aketajawe Lolobata, Halmahera,
Indonesia. Dua jenis Begonia masuk ke dalam seksi Petermannia berdasarkan pengamatan material baru yang tersedia.
Sebagai tambahan, perbaikan pertelaan dan ilustrasi telah diberikan. Kunci identifikasi jenis Begonia dari Maluku juga
disajikan dalam tulisan ini.
Kata kunci: Begonia, jenis baru, Halmahera.
REINWARDTIA 20 [VOL.14
scribed: Begonia sageaensis Wiriad. (Wiriadinata,
2012). Only six species of Begonia have been re-
ported from the islands altogether (Hughes, 2008;
Wiriadinata, 2012), but this is certainly an underes-
timate. Expeditions to less-explored areas of other
central Malesian islands such as Sulawesi have re-
cently brought to light numerous new species
(Thomas et al., 2009a, Thomas et al., 2009b, Tho-
mas et al., 2011), and it has been noted that “it is
evident from herbarium collections that a number of
endemic species remain to be described” from the
Moluccas (Hughes, 2008).
The six species previously reported from the
Moluccas comprise two endemic Moluccan species,
the previously poorly known Begonia holosericea
and B. sageaensis as well as the more widely dis-
tributed B. aptera Blume, which also occurs on Su-
lawesi, and three closely related species (B. brachy-
botrys Merr. & L.M. Perry, B. pseudolateralis
Warb., and B. rieckei Warb.) which fall in the Bego-
nia reickei species complex, which shows a wide
distribution in Malesia east of Huxley’s Line
(Hughes, 2008). This paper presents an updated
description of B. holosericea and provides descrip-
tions of two new species of endemic Moluccan Be-
gonia, raising the total number of species known
from the Moluccan Islands to eight, four of which
being endemic.
Begonia holosericea was previously only known
from the type material and information on important
characters such as placentation type was lacking.
This is why Doorenbos et al. (1998) only tentatively
assigned the species to section Petermannia and
indicated that the placement was doubtful. Hughes
(2008) emphasized that the sectional placement of
the species is unknown. New material, including
plants cultivated at Bogor and Bali Botanic Gardens
and herbarium material deposited in BO, has re-
cently become available as a result of expeditions to
the Moluccas. Based on this material Begonia
holosericea is here placed in section Petermannia,
as it exhibits typical characters of the section: proto-
gynous inflorescences, two-tepaled male flowers,
anthers with unilaterally positioned slits, five-
tepaled female flowers, two-flowered female inflo-
rescences or solitary female flowers, three-locular
ovaries with axile placentation and bilamellate pla-
centae, and fruits with equal or subequal wings.
Thus all Moluccan Begonia species, except for Be-
gonia aptera (section Sphenanthera), can be as-
signed to section Petermannia.
Recent expeditions to the Moluccas, carried out
through a partnership between Bogor Botanic Gar-
den and Fairchild Tropical Botanic Garden (June-
August 2011, and June-August 2012) to commemo-
rate a historic expedition to the region led by David
Fairchild in 1940, have resulted in many valuable
herbarium and living specimens, a number of which
may represent new species. Two of them are de-
scribed below. Like the majority of Moluccan spe-
cies, they are classified in Begonia section Peter-
mannia. All available Begonia specimens from BO,
E, K, L and SING have been consulted, and hence it
must be assumed, at least until more intensive col-
lecting may reveal otherwise, that these new species
have restricted ranges and are endemic to Hal-
mahera island (Fig. 1). Diagnostic characters of the
two new species and Begonia holosericea are illus-
trated in Figs. 2–4.
Identification key to Begonia species in the
Moluccan Islands
1.a. Plants erect ………………………………… 2
1.b. Plants creeping …………………………….. 3
2.a. Female flowers with 2–5 tepals; male flowers
with 2 tepals, anther connectives not projecting
at apex; leaves broadly ovate ………Begonia
rieckii Warb
2.b. Female flowers with 6 tepals; male flowers
with 4 tepals, anther connectives projecting at
apex; leaves oblong-lanceolate ………Begonia
aptera Blume
3.a. Leaf apex acuminate ……………………..… 4
3.b. Leaf apex rounded ……………………. …... 5
4.a. Adaxial leaf surface densely hirsute with red
hairs; female inflorescence peduncle < 5 mm;
female flowers solitary …. Begonia sageaensis
Wiriad.
4.b. Adaxial leaf surface glabrous; female
inflorescence peduncle up to 3.5 cm; female
flowers in two-flowered inflorescences ……
Begonia holosericeoides Ardi & D.C. Thomas
5.a. Male flower with two tepals; female
inflorescence peduncle 2–3 mm long; ovary
densely hairy ……………………... Begonia
holosericea (Teijsm. & Binn.) Teijsm. & Binn.
5.b. Male flowers with four tepals; female
inflorescence peduncle ca. 1 mm long; ovary
glabrous or glabrescent ……………. Begonia
aketajawensis Ardi & D.C. Thomas
SPECIES DESCRIPTIONS
Begonia aketajawensis Ardi & D.C. Thomas sp.
nov. sect. Petermannia. Figs. 1, 2. ― Type:
Indonesia, North Halmahera, Aketajawe-Lolobata
National Park, Tayawi Village, secondary lowland
forest, 0o27’55.6’’N, 127o44’42.3’’E, 19 May 2011,
2014] 21
ARDI et al.: Begonia of the Molucca Islands I
Melissa E. Abdo 4740 (holo: BO).
Similar to Begonia holosericea Differing from that
species by the narrowly obovate to orbicular leaves,
smaller leaf size (8.8–12 × 8.3–11 cm), male
flowers with four tepals, and sparsely hairy or
glabrous ovaries (leaf laminas broadly ovate to sub-
orbicular, 15–19 × 12–18 cm, male flowers with
two tepals, and densely hairy ovaries in B. holos-
ericea).
Perennial, monoecious herb with creeping stems, to
ca. 25 cm long, moderately to densely hairy. Stems
few branched; internodes ca. 1.7–3.8 cm long,
densely covered with branched hairs. Leaves
alternate; stipules persistent, 8–13 × 5–6 mm, trian-
gular, translucent glabrous except for hairs on the
abaxial midrib, midrib abaxially prominent, project-
ing up to ca. 3.5 mm at the apex; petioles 3.5–11.5
cm long, channeled, red, densely covered with
branched hairs; lamina basifixed 8.8–12 × 8.5–11
cm, asymmetric, narrowly obovate to orbicular,
base slightly rounded to cordate, lobes not or rarely
slightly overlapping, apex rounded, margin fimbri-
ate, adaxial surface green or reddish green
variegated, with silvery band or spots around the
margin and extending inwards between the veins,
glabrous, abaxial surface paler, hairy on the veins,
primary veins 7–8, actinodromous, secondary veins
craspedodromous. Inflorescences axillary,
protogynous; bracts ca. 7–13 × 4–6 mm, ovate,
creamy tinged pink, sparsely hairy, with abaxially
slightly prominent midrib projecting up to 3 mm at
the apex; female inflorescences solitary, usually one
node basal to the male inflorescences, peduncles ca.
1 mm long; male inflorescences usually distal to the
female inflorescences, composed of 1–2 monocha-
sial partial inflorescences with 2–4 flowers each,
peduncles 2–3.5 cm long. Male flowers: pedicels 3–
5.5 cm long; tepals 4, white, the 2 larger 11–15.5 ×
11.5–15 mm, orbicular, base slightly cordate, apex
rounded, the 2 smaller 10–12.5 × 3–7 mm, elliptic
Fig. 1. Distribution of Begonia holosericeoides (triangle), B. aketajawensis (circle), B. holosericea (square).
REINWARDTIA 22 [VOL.14
or oblong-obovate; stamens yellow, filaments ca.
0.5–1 mm long, slightly fused at the very base, an-
thers ca. 1–1.5 mm long, oblong, dehiscing through
unilaterally positioned slits >1/2 as long as the an-
thers. Female flowers: pedicels 1.7–2.5 cm long;
tepals 5–6, white tinged with pink, unequal, the 4
larger 10.5–15 × 8–11 mm, obovate, the smallest 11
–15 × 5–7 mm, elliptic; ovary globoid 8.5–10 × 7–
10 mm, locules 3, placentation axile, placentae
bilamellate, wings 3, narrowly triangular, rounded
at base, apex subtruncate to truncate, style basally
fused, 3-branched, each stylodium bifurcate in the
stigmatic region, stigmas 3, stigmatic surface a
spirally twisted papillose band, yellow. Fruiting
pedicels ca. 25 mm long. Fruits globoid, 8.5–13 × 7
–10 mm (excluding the wings), glabrous, dehiscent,
splitting along the wing attachment, wing shape as
for ovary, ca. 5.5 mm wide at the widest point (at
the apex); seeds unknown.
Distribution. Endemic to Aketajawe-Lolobata Na-
tional Park, Halmahera, North Moluccas, Indonesia.
Locally common.
Habitat. Found on vertical moist rock surfaces, in-
cluding limestone substrates, in half to full shade, in
secondary forest at 100–150 m altitude.
Other specimen examined. Cultivated at Bali
Botanic Garden from vegetative material collected
in the wild (Indonesia, North Maluku, Halmahera
Timur, Aketajawe-Lolobata National Park), 1.ix.
2013, Wisnu H. Ardi, WI 84 (BO).
Note. The specific epithet refers to the collection
locality of the type material, Aketajawe-Lolobata
Fig. 2. Begonia aketajawensis Ardi & D.C. Thomas. A. Plant habit in-situ (scale 10 cm); B. Juvenile plant in-situ
(scale 5 cm); C. Cultivated juvenile plant (scale 2 cm); D. Male inflorescence (scale 2 cm); E. Male flowers (scale 1
cm); F. Female flower (scale 1 cm); G. Female flower (scale 1 cm); H. Infructescence (scale 1 cm); I. Ovary cross
section (scale 5 mm). (Photos: A & D-H: Made Ardhaka; B: Yayan Wahyu; C: Wisnu H. Ardi; I: Daniel C. Thomas).
2014] 23
ARDI et al.: Begonia of the Molucca Islands I
National Park (Latin, -ensis – originating from).
Begonia aketajawensis is similar to Begonia holos-
ericea, but it can be easily distinguished by several
characters such as leaf shape and size (narrowly
obovate to orbicular leaves with laminas 8.8–12 ×
8.3–11 cm, versus broadly ovate to suborbicular
leaves with laminas 15–19 × 12–18 cm), male
flowers with four tepals (versus male flower with
two tepals) and sparsely hairy or glabrous ovaries
(versus densely hairy ovaries with stiff, red hairs in
B. holosericea). Begonia aketajawensis shows a
character combination which is unique in the large
section Petermannia (>270 species): creeping stems
and four-tepaled male flowers. Four-tepaled male
flowers are rare in section Petermannia and have
only been described from a few species such as B.
georgei Coyle, B. grandipetala Irmsch., B.
propinqua Ridl., and B. watuwilensis Girm., none
of which is morphologically close to B.
aketajawensis. The majority of species in section
Petermannia shows more or less erect stems, al-
though there are some exceptions such as the rhizo-
matous B. mendumae M. Hughes and the creeping
B. gemella Warb. ex L. B. Sm. & Wassh. In contrast
to this, the Begonia species in section Petermannia
endemic to the Moluccas are characterized by
creeping or rhizomatous stems. Another characteris-
tic feature of the endemic Moluccan species are the
Fig. 3. Begonia holosericeoides Ardi & D.C. Thomas. A. Plant habit in-situ (scale 10 cm); B. Plant habit in
cultivation (scale 10 cm); C. Stipule (scale 1 cm); D. Male inflorescence (scale 2 cm); E. Female inflorescence (scale
1 cm); F. Male flower (scale 1 cm); G. Female flower (scale 1 cm); H. Ovary cross section (scale 5 mm). (Photos: A:
Yayan Kusuma; B-H: Wisnu H. Ardi).
REINWARDTIA 24 [VOL.14
few-flowered (2–5 flowers) male inflorescences
which are arranged in simple monochasia.
Begonia holosericeoides Ardi & D. C. Thomas sp.
nov. sect. Petermannia. Figs. 1, 3. ― Type:
Cultivated at Bogor Botanic Garden from vegetative
material collected in the wild (Indonesia, North
Maluku, Halmahera Timur, Aketajawe-Lolobata
National Park, SP2 Village, primary lowland forest,
1o 26’05.6”N 128o 37’30.20”E, 1 September 2013,
Wisnu H. Ardi, WI 83 (holo: BO, iso: KRB).
Similar to Begonia holosericea (Teijsm. & Binn.)
Teijsm. & Binn. Differs from this species by the
longer peduncles of the female inflorescences (1.1–
3.5 cm), sparsely hairy or glabrous ovaries and
ovate leaves with acuminate apex (peduncle of the
female inflorescence 2–3 mm long, ovary densely
hairy and leaves suborbicular with rounded apex in
B. holosericea).
Perennial, monoecious herb with creeping stems, to
ca. 15 cm long. Stems few branched; internodes ca.
10–12 mm long, dark green or green tinged red,
densely covered with branched hairs. Leaves
alternate; stipules persistent, ca. 7–12 × 9–12.5 mm,
triangular, glabrous except for hairs on the abaxial
midrib, midrib abaxially prominent, projecting up to
ca. 4 mm at the apex; petioles 3–4 cm long, red,
densely covered with hairs; lamina basifixed, 15–
15.5 × 10.5–11 cm, asymmetric, ovate, base cordate
and lobes not or slightly overlapping, apex acumi-
nate, margin fimbriate, adaxial surface glabrous,
dark green reddish, variegated with silver bands or
spots between the veins sometimes fused forming a
band along the margin, abaxial surface pale green,
with red hairs on the veins, coriaceous, primary
veins 7–8, actinodromous, secondary veins craspe-
dodromous. Inflorescences: axillary, protogynous;
bracts 8–14 × 4–8 mm, oblong, reddish, sparsely
hairy, with abaxially slightly prominent midrib pro-
jecting up to 2 mm at the apex; female
inflorescences two-flowered, usually one node basal
to the male inflorescences, peduncles ca. 1.1–3.5
cm long; male inflorescences usually distal to the
female inflorescences, composed of 1–3 partial in-
florescences, each consisting of 2 monochasia with
2–4 flowers each, peduncles ca. 5–8 cm long, hairy.
Male flowers: pedicels 1.5–4 cm long, hairy; tepals
2, white tinged with pink, 13–15 × 11–13 mm,
broadly ovate, base slightly cordate and becoming
rounded at anthesis, apex rounded, abaxially
glabrescent; stamens yellow, filaments ca. 1–2 mm
long, slightly fused at the very base, anthers ca. 1.5
–2 mm long, oblong, dehiscing through unilaterally
positioned slits >1/2 as long as the anthers. Female
flowers: pedicels 2.2–3.1 cm long, sparsely hairy,
red; tepals 5, white tinged with pink at the margin,
unequal, the four larger broadly ovate, 14 × 11–12
mm, one smaller, elliptic, 11 × 5 mm, margin fim-
briate; ovary ellipsoid, 12.5 × 4.5 mm (excluding
the wings), locules 3, placentation axile, placentae
bilamellate, wings 3, subequal, cuneate to rounded
at base, subtruncate at apex, widest point apically,
style basally fused, 3-branched, each stylodium
bifurcate in the stigmatic region, stigmas 3,
stigmatic surface a spirally twisted papillose band,
yellow. Fruiting pedicels ca. 2.2–3.1 cm long.
Fruits ellipsoid, 10–13 × 4.5–5.5 mm (excluding
the wing), sparsely hairy or sometimes glabrous,
dehiscent, splitting along the wing attachment, wing
shape as for ovary, ca. 9 mm wide at the widest
point (at the apex); seeds unknown.
Distribution. Endemic to the Aketajawe-Lolobata
National Park, Halmahera, North Mollucas, Indone-
sia.
Habitat. Found on vertical moist rock surfaces, in-
cluding limestone substrates, in full shade, in
primary rain forest at ca. 145 m asl.
Note. The specific epithet is a compound of holos-
ericea (the species epithet of Begonia holosericea),
and -oides (in Greek compounds: resembling). It
refers to the creeping habit and adaxial leaf pattern,
which are similar to the conditions found in B.
holosericea. Although similar on first sight, Bego-
nia holosericeoides can be easily distinguished by
several characters such as the acuminate leaf apex
(rounded in B. holosericea) and the sparsely hairy
to glabrous ovary (densely hairy with stiff, red hairs
in B. holosericea) and the length of the peduncles of
the female inflorescences (0.2–0.3 cm in B. holos-
ericea, versus 1.1–3.5 cm in B. holosericeoides).
BEGONIA HOLOSERICEA (Teijsm. & Binn.)
Teijsm. & Binn., Epim. Ludg. Bat.: 5(1863). Sect.
Petermannnia. ― Diploclinium holosericeum
Teijsm. & Binn., Tijdschr. Ned.-Indie 25:421
(1863). ― Type: Ternate Island, J.E. Teijsmann s.n.
(holo: BM), Figs. 1, 4.
Perennial, monoecious herb with creeping stems, to
ca. 25 cm long. Stems few branched; internodes ca.
2–4.5 cm long, reddish, densely covered with
branched hairs, which are red at base, and white at
the apex. Leaves alternate; stipules persistent, 13–16
× 9–12 mm, triangular, glabrous except for hairs on
the abaxial midrib, midrib abaxially prominent, pro-
jecting up to ca. 12 mm at the apex; petioles 7–11.5
cm long, red, densely covered with branched hairs;
2014] 25
ARDI et al.: Begonia of the Molucca Islands I
lamina basifixed, 15–19 × 12–18 cm, asymmetric,
broadly ovate to suborbicular, base cordate and
lobes overlapping, apex rounded, margin fimbriate,
adaxial surface glabrous, bullate, variegated, green
with silvery green blotchs or spots between the
veins and forming bands, abaxial surface pale
green, hairy on the veins, primary veins 7–8,
actinodromous, secondary veins craspedodromous.
Inflorescences: axillary, protogynous; bracts: ca.
15 × 8 mm, ovate, creamy tinged pink, sparsely to
moderately hairy, with abaxially slightly prominent
midrib projecting up to 6 mm at the apex; female
inflorescences one- or two-flowered, usually one
node basal to the male inflorescences, peduncles 2–
3 mm long; male inflorescences usually distal to the
female inflorescences, composed of 1–3(–5) partial
inflorescences, each consisting 1–2 monochasia
with 2–4 flowers each, peduncles ca. 3–5 cm long,
hairy. Male flowers: pedicels 3–4 cm long, hairy;
tepals 2, white tinged with pink, 10–17 × 10–13
mm, broadly ovate, base slightly cordate and be-
coming rounded at anthesis, apex rounded;
abaxially hairy, stamens yellow, filaments ca. 1
mm, slightly fused at the very base, anthers ca. 1–
1.5 mm long, oblong, dehiscing through unilaterally
positioned slits >1/2 as long as the anthers. Female
flowers: pedicels 3–4.2 cm, hairy, red; tepals 5,
white tinged with pink at the margin, unequal, the
four larger broadly ovate and adaxially concave (+/-
bowl-shaped), 10–14 × 10–12 mm, one smaller,
elliptic, 10–13 × 5–6 mm, margin fimbriate; ovary
ellipsoid, 9–11 × 5–7 mm, red, densely hairy,
Fig. 4. Begonia holosericea (Teijsm. & Binn.) Teijsm. & Binn. A. Plant habit in-situ (scale 5 cm); B. Plant habit in
cultivation (scale 5 cm); C. Stipule (scale 1 cm); D. Male inflorescence (scale 1 cm); E. Female inflorescence and
flower (scale 1 cm); F. Ovary cross section (scale 5 mm). (Photos: A & D: Izu A. Fijridiyanto.; B, C, E, F: Wisnu H.
Ardi).
REINWARDTIA 26 [VOL.14
locules 3, placentation axile, placentae bilamellate,
wings 3, subequal, rounded to cuneate at base, trun-
cate to rounded at apex, widest point apically, style
basally fused, 3-branched, each stylodium bifurcate
in the stigmatic region, stigmas 3, stigmatic surface
a spirally twisted papillose band, yellow. Fruiting
pedicels 3.5–4.2 cm long. Fruits ellipsoid, 11–18 ×
10–11 mm (excluding the wing), densely hairy, de-
hiscent, splitting along the wing attachment, wing
shape as for ovary, reddish, ca. 12 mm wide at the
widest point (at the apex); seeds unknown.
Distribution. Endemic to Mt. Gamalama, Ternate
Island, North Moluccas, Indonesia.
Habitat. This species can be found growing in
shady places on vertical moist rock surfaces, in sec-
ondary forest at ca. 600 m altitude.
Other specimen examined. Cultivated at Bogor
Botanic Garden from vegetative material collected
in the wild (Indonesia, North Moluccas, Ternate
Island, Mt. Gamalama), 6.i.2014, Wisnu H. Ardi, WI
95 (BO).
Note. Begonia holosericea is the first endemic
species described from Ternate island on the basis
of a specimen collected by Teijsmann. The species
was initially described as Diploclinium
holosericeum, but later referred to Begonia. Sec-
tional placement was problematic for this species as
information about its placentation was lacking, and
Doorenbos (1998) and Hughes (2008) only tenta-
tively assigned it to section Petermannia. Based on
recent observations of plants cultivated in Bogor
Botanic Garden, which were collected from the type
locality in 2009, B. holosericea can be confidently
assigned to section Petermannia 150 years after it
was first described. It exhibits several typical
characters of the section: protogynous inflorescen-
ces, two-tepaled male flowers, anthers with unilater-
ally positioned slits, five-tepaled female flowers,
two-flowered female inflorescences or solitary fe-
male flowers which are born basal to the male, three
-locular ovaries with axile placentation and bilamel-
late placentae, and fruits with equal or subequal
wings.
Acknowledgement
The authors would like to express gratitude to Mustaid
Siregar and Joko R. Witono (Bogor Botanic Gardens),
and to Hong Liu and Javier Francisco-Orteg (Fairchild
Tropical Botanic Garden & Florida International Univer-
sity) for their support, and to Dr. Izu Andry Fijridiyanto
(Bogor Botanic Gardens), I Made Ardhaka and Kadek
Erosi Undaharta (Bali Botanic Gardens) for giving per-
mission to use their pictures. The authors are also thank-
ful for cooperation in the field and logistical support
from Mahroji and David Purmiasa. Irfan Rosadi, Hanom
Bashari, and other colleagues from Burung Indonesia
provided invaluable assistance and collaboration. The
permits for fieldwork provided by RISTEK and Aketa-
jawe-Lolobata National Park are also appreciated. Fund-
ing support was provided by Fairchild Tropical Botanic
Garden and Bogor Botanic Gardens-LIPI.
References
DOORENBOS, J. M., SOSEF, S. M. & DE WILDE, J.
J. F. E. 1998. The sections of Begonia including
descriptions, keys and species lists. Studies in
Begoniaceae VI. Wageningen Agricultural University
Papers 98 (2). Wageningen: Wageningen
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