ADDITIONS TO THE BEGONIA FLORA OF SARAWAK, BORNEO, I: TWELVE NEW SPECIES AND A NEW RECORD
Author
Julia, S.
Sarawak Herbarium, Forest Department Sarawak, KM 10 Jalan Datuk Amar Kalong Ningkan, 93250 Kuching, Sarawak, Malaysia. & Author for correspondence. E-mail: juliasang 12 @ gmail. com.
juliasang12@gmail.com
Author
Kiew, R.
Forest Research Institute Malaysia, 52109 Kepong, Selangor, Malaysia.
Author
Ling, C. Y.
Sarawak Herbarium, Forest Department Sarawak, KM 10 Jalan Datuk Amar Kalong Ningkan, 93250 Kuching, Sarawak, Malaysia.
text
Edinburgh Journal of Botany
2022
2022-08-18
79
410
1
46
http://dx.doi.org/10.24823/ejb.2022.410
journal article
285459
10.24823/EJB.2022.410
b44efdf4-f377-4fa4-a2ee-00776e4fd78c
1747-0036
10523329
8.
Begonia latifolia
S.Julia & C.Y.Ling
,
sp. nov.
Similar to
Begonia celata
S.Julia & Kiew
in its habit but differs in having longer internodes,
2–5.5 cm
(versus
0.7–2 cm
long); much larger bracts, 10–20 ×
15–25 mm
(versus 6–11 ×
3–5 mm
); fewer bracteoles, up to 5 pairs (versus 12 pairs); wider lower bracteoles,
6–10 mm
(versus
4 mm
wide), and upper bracteoles,
4–8 mm
(versus
2–3 mm
wide); fewer stamens, 15–20 (versus 28–35); and smaller female flowers with ovary 4–5 ×
5–6.5 mm
(versus 6–7 ×
8–9 mm
).
– Type:
Malaysia
,
Borneo
, Sarawak,
Kapit District
,
Baleh
,
Kakap Camp
,
Sungai Bekakap
,
1°21′55′′N
,
113°43′31′′E
,
9 iii 2016
,
Ling
et al.
SFC 5907
(
holotype
SAR
!,
isotype
KEP
!).
Figure 9
.
Creeping herb,
4–8 cm
long. Stem, stipule and petiole densely hirsute, hairs c.
3 mm
long, magenta, sometimes white on juvenile plants.
Stems
red brown, little branched, succulent,
3.5–6 mm
thick, internodes
2–5.5 cm
long, slightly thicker at nodes.
Stipules
pale green to yellow green, sometimes reddish at base, broadly ovate, 1.3–2.8 ×
1.4–2.7 cm
, keeled, margin ciliate, apex acute or rounded, persistent.
Leaves
alternate, distant, oblique, held horizontally, upper lamina surface and lower veins densely hirsute, hairs magenta, sometimes white on upper leaf surface and on juvenile plants, c.
3 mm
long; petioles red brown, (1.5–)
3–7.5 cm
long, terete or slightly grooved above; lamina dark green above, pale green beneath, in life succulent, matt, asymmetrical, ovate, 5.5–9.5 ×
6.5–12 cm
, broad side
3.6–8 cm
wide, base cordate, sometimes overlapping, basal lobes
1–2 cm
long, margin minutely dentate and ciliate, apex acuminate, acumen
3–5 mm
long; venation pinnate-palmate, veins green, above reddish near base, beneath pale green, pale brown near base, 4 pairs from the base and 2 veins on either side of the midrib, 1 or 2 veins in basal lobe, slightly impressed above, prominent beneath.
Inflorescences
protogynous, in upper leaf axils, racemose to
3–5 cm
long, peduncle glabrous,
2.3–2.5 cm
long; bracts similar to stipules, pale green or yellow green, reddish at base, ovate, 10–20 ×
15–25 mm
, margin ciliate, persistent; bracteoles to 5 pairs, lower bracteoles pale green, reddish at base, 9–12 ×
6–10 mm
, margin ciliate, sometimes sparsely hirsute, hairs red, upper bracteoles pale green, reddish at base, ovate 4–6 ×
4–8 mm
, margin ciliate or irregularly serrate, apex emarginate, persistent.
Male flowers
: pedicel white,
8–10 mm
long, glabrescent; tepals 4, pink, deep pink near base, glabrous, margin entire, apex broadly acute to rounded, outer two tepals elliptic, 9–11 ×
5–6 mm
, inner two tepals lanceolate, 7–9.5 ×
1.5–2 mm
; stamens 15–20, cluster conical, sessile; filaments pale yellow, c.
1 mm
long; anthers pale yellow, obovate, c.1.5 ×
1 mm
, apex emarginate.
Female flowers
: sessile, enclosed by 2 or 3 bracteoles; ovary white or pale green, obovate, ovary including the wings 4–5 ×
5–6.5 mm
, glabrous, wings 3, unequal, locules 3, placentas 2 per locule; tepals 5, pinkish, glabrous, margin entire, apex acute, outer three tepals elliptic, 8–8.5 ×
4–5 mm
, inner two tepals narrowly elliptic to lanceolate, 8–9 ×
2–2.5 mm
; styles 3, pale yellow, c.
3 mm
long, divided to base; stigma pale yellow, anchor-shaped, papillose forming a continuous twisted band.
Capsule
not seen.
Figure 9.
Begonia latifolia
S.Julia & C.Y.Ling
,
sp. nov.
A, Habit and habitat; B, stipule; C, juvenile leaf; D, inflorescence; E and F, male flower; G and H, female flower; I, cross-section of ovary. All photographs of the type specimen,
Ling
et al. SFC 5907, taken by C. Y. Ling.
Distribution
.
Malaysia
(
Sarawak
). To date, known only from Kapit District (see
Figure 1
).
Habitat
. Riparian forest on rocks and stream banks, at elevations to
313 m
.
Etymology
. Latin,
lati
- (‘broad’) and
folius
(‘leaf’), referring to its lamina broader than long.
Begonia latifolia
is uncommon where it occurs. Compared with
Begonia bosuangiana
from
Sabah
, this species is larger, with stem
4–8 cm
long (versus low herb to
4 cm
tall); longer internodes,
2–5.5 cm
(versus
1–1.5 cm
long); larger lamina, 5.5–9.5 ×
6.5–12 cm
(versus c.5 ×
5.3 cm
); and conspicuously larger lower bracteoles, 4–12 ×
6–10 mm
(versus 1–2.5 ×
1–2 mm
).