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ISSN 1346-7565 Acta Phytotax. Geobot. 60 (3): 123–126 (2011)
Studies on the Alocasia Schott (Araceae-Colocasieae) of Borneo II:
Alocasia baginda, a New Species from Eastern Kalimantan,
Indonesian Borneo
Agung KurniAwAn1,
*
And Peter C. BoyCe2
1Bali Botanic Garden, Indonesian Institute of Sciences, Candikuning, Baturiti, Tabanan, Bali, 82191, Indonesia.
*agung _ kurnia1@yahoo.com (author for correspondence); 2Pusat Pengajian Sains Kajihayat
[School of Biological Sciences], Universiti Sains Malaysia, 11800 USM, Pulau Pinang, Malaysia
Alocasia baginda Kurniawan & P. C. Boyce is described and illust rated from an unspecied localit y in
easter n Kalimantan, Indonesian Bor neo, and is inserted into a modied key to Bornean Alocasia. Rec-
ognition of A. baginda takes to 23 the Alocasia described from Borneo, of which 22 are endemic.
Key words: Araceae, Alocasia, Borneo, endemic, Kalimantan
Hay (1998) recognized 19 indigenous Aloca-
sia species for Borneo, of which 18 are strictly
Borneo endemic, many very locally so, with the
other (A. robusta M. Hotta) extending as far as
the Anambas Islands. Eight of Hay’s species were
then novel. Subsequently, an additional three new
species have been described for Borneo (Hay
2000, Boyce 2007), all endemic. Since 2002 eld-
work by the second author has revealed a 14 fur-
ther undescribed (as yet not worked up) species in
Sarawak, while a recent somewhat cursory exam-
ination of herbarium material from Sabah (KNP
& SAN) indicated at least six additional novel-
ties. This total of 42 taxa is overwhelmingly
based on collections from Sarawak, Sabah, and
Brunei (i.e., less than one third of the total land-
mass of Borneo). Kalimantan, comprising more
than 70% of the land area of Borneo, remains
very poorly known, and it is thus highly probable
that Borneo harbors at least 50 Alocasia species,
the overwhelming majority of which can be ex-
pected to be endemic.
Alocasia baginda A. Kurniawan & P. C. Boyce,
sp. nov.—Fig. 1
Alocasiae melo proxima, insigniter foliis rigidissimis
crasse coriaceis fere perfecte peltatis, sed prompte dis-
tinguenda foliis adaxialiter laevibus (non subtiliter et val-
de r ugosis) atro-opace viridibus par tibus disparibus pal-
lide griseis bullatis. In orescentiae specierum ambarum
a prima visione leviter similissimae, sed in A. baginda
spathae constrictio circa in parte media zonae orum sta-
minataru m, dum in A. melo in parte apicali.
Typus. Indonesian Borneo, ex easter n Kalimantan,
without exact locality, cultivated in Bali Botanic Garden,
Indonesian Institute of Sciences-LIPI (Kebun Raya Eka
Karya Bali), under Garden Accession E20081015 (holo-
THBB [dried specimens and inorescences in alcohol];
iso- BO!, K!, L!)
Small rather robust terrestrial herb 25–30 cm
tall; stem shortly erect, developing in age into a
short decumbent rhizome. Leaves up to 4 togeth-
er, spreading; petioles 13–23 cm long, short
sheathing in the lower 1/6–1/7, glabrous, pale
green with scattered white speckles in the lower
part; sheath persistent; leaf blade very broadly
ovate to sub-orbicular, peltate, 10–18 cm long,
124 Vol. 61Acta Phytotax. Geobot.
Fig. 1. Alocasia baginda Kurniawan & P. C. Boyce. A: Type plant i n cultivat ion. B: Leaf blade, adaxial surcace. Note the pale
gray bullae. C: Leaf blade, abaxial surface showing the red venation. D: Freshly opened inorescence. E: Inorescence at
late male anthesis, lower part of spathe par tially removed. Note that the spathe li mb is now semi-translucent. F: Detail of
the pistillate and staminare ower zones. Note that the lowermost syna ndrodes are divided into staminodes. Note, too, the
ascending pistils. Images by Dewi Lestar i and Gede Wawan Setiadi.
February 2011 125
Agung Kurn iAwAn
&
BoyCe
—A New Alocasia f rom Kalimantan
7–12 cm wide, stify and thickly coriaceous, ad-
axially matte dark green, with contrasting pale
grey bullate portions blade dened by the prima-
ry and marginal veins, pale green abaxially, with
the distal part of the midrib, primary and mar-
ginal veins deep red, apex acuminate to apiculate
for ca. 1 cm, thence mucronate for 4 mm; poste-
rior lobes united for 75–90% of their length, 1/2–
1/3 the length of the anterior, with the posterior
costae diverging at 20°, anterior midrib with 3–4
primary lateral veins on each side, diverging at
35° (distal ones) to 80–85° (proximal ones); sec-
ondary venation impressed adaxially. Inores-
cence pairs solitary, each subtended by narrowly
membranous prophyll and surrounded by a single
membranous cataphyll; peduncle 12–13 cm long,
greenish white, exceeding cataphyll; spathe 5–6
cm long; lower spathe abruptly constricted 1.5–2
cm from the base, lower spathe ovoid; spathe
limb erect even after anthesis, narrowly elliptic-
triangular, 3–3.5 cm long, acuminate for ca. 5
mm, externally creamy white, interior glossy
creamy white, deep red along the limb margin as
far as constriction, limb late in anthesis becom-
ing somewhat semi-translucent with the venation
remaining opaque, thence semi-deliquescent;
spadix distinctly shorter than to subequalling the
spathe, 4–4.5 cm long, stipitate; stipe cylindrical,
2–3 mm long, creamy white; pistillate ower
zone 6–7 mm long or about 1/5 the spadix length;
pistils rather loosely arranged, ascending; ova-
ries ovoid, 1.5–2 mm long, ca. 1.5 mm diam.,
greenish to ivory; style short 0.5–1 mm, < 1 mm
diam.; stigma 2–3-lobed, the variation in lobe
number present in a single inorescence, creamy
ivory; sterile interstice slender, 2–3mm long,
partly naked below and with 6–7 synandrodia
above; lowermost synandrodia deeply lobed into
almost separate staminodes, the rest rhombohex-
agonal in plain view, 1–1.5 mm diam.; staminate
ower zone cylindric to subcylindrid, 10–11 mm
long, ca. 1/4 the length of the spadix, 1/3–1/2 held
within the lower spathe chamber, ivory; synan-
dria densely arranged, rhombohexagonal in plan
view, convex-topped, 1–1.5 mm diam.; thecae
slightly overtopped by the synconnective; appen-
dix 1.75–2 cm long, ca. spadix length, narrowly
conic, pale cream. Infructescence and fruits un-
known.
Distribution. Eastern Kalimantan, without
exact locality.
Ecology. Unknown. The species to which A.
baginda shares closest morphological similarities
are locally endemic and obligately associated
with limestone (e.g., A. regina N. E. Br.—NE
Sarawak: Mulu and A. reginula A. Hay—E
Sabah: Bukit Tabin), or ultramacs (A. melo A.
Hay, P. C. Boyce & K. M. Wong—E Sabah: Telu-
pid). It is expected that A. baginda will reveal
similar geological preference once it is relocated
in the wild. It is perhaps worth to note that A.
baginda most closely resembles A. melo and A.
reginula and that perhaps a search of ultramac
and limestone outcrops is in order.
Etymology. The trivial epithet is from the Ba-
hasa Indonesia honoric title denoting ‘King’ or
‘Majesty’. The choice was inuenced by the ‘tra-
dition’ of applying regal epithets in the genus
Alocasia, notably to species, such as this, with
considerable horticultural merit.
Notes. Alocasia baginda most closely resem-
bles A. melo, notably in the very stify thickly
coriaceous almost completely peltate leaf blades
and pale green glabrous petioles. Vegetatively it
is readily distinguished from A. melo by the leaf
blades adaxially smooth (not nely and strongly
rugose), and dark matte green, with contrasting
pale grey bullate portions of the blade. Inores-
cences of both species are supercially very sim-
ilar, although the spathe constriction in A. bagin-
da is situated about mid-way up the staminate
ower zone; whereas that of A. melo coincides
with the top of the staminate zone, resulting in
both the staminate and pistillate zones being en-
closed in the lower spathe.
Alocasia reginula also closely approaches A.
baginda, but is readily differentiated by leaf
blades adaxially very dark black-green with
white primary and secondary venation, and with
wholly deep red abaxial surfaces.
126 Vol. 61Acta Phytotax. Geobot.
We wish to thank Lars Nauheimer (Systematic Botany,
Ludwig Maximilians University, München, Germany) for
drawing our attention to this plant during a recent visit to
Bali. We are especially grateful to Dewi Lestari and Gede
Wawan Setiadi for the photog raphs. We thank Dyan
Meiningsasi S.P. who brought this species from a nursery
in Malang, East Java to be cultivated in Bali Botanic Gar-
den. Many thanks to J. F. Veldkamp (L) for providing the
Latin diagnoses.
References
Boyce, P. C. 2007. Studies on the Alocasia Schott (Arace-
ae-Colocasieae) of Borneo I: Two new species from
Sarawak, Malaysian Borneo. Gard. Bull. Singapore
58(2): 141–154.
Hay, A. 1998. The genus Alocasia (Araceae-Colocasieae)
in West Malesia and Sulawesi. Gard. Bull. Singapore
50: 221–334.
Hay, A. 2000. Alocasia nebula. Curtis’s Bot. Mag. 17(1):
14–18, pl. 381.
Received September 21, 2010; accepted January 22, 2011
16. Adaxial leaf blade surface strongly and minutely rugose with the tertiary venation raised. (ultramacs:
Sabah) ....................................................................................................................................................... A. melo
16a. Adaxial leaf blade surface smooth, secondary venation impressed or not ................................................. 17
17. Leaf blade variegated .......................................................................................................................................18
17a. Leaf blade not variegated ...............................................................................................................................20
18. Leaf blades thickly and stify subsucculent, adaxially matte .......................................................................19
18a. Leaf blades thinly leathery, somewhat glossy (limestones: SW Sarawak) .....................................A. reversa
19. Adaxial leaf blade surface very dark black-green with white impressed primary and secondary venation;
abaxial surface deep red (limestone: Sabah: Bukit Tabin) ................................................................ A. reginula
19a. Leaf blades adaxially dark green with conspicuous pale grey bullae; abaxial sur face palegreen with the
distal portion of mid-rib, and primary and marginal veins deep red (Eastern Kalimantan) .......... A. baginda
20. Leaf blades with conspicuous intramarginal vein and marginal vein; laminae broadly to narrowly elliptic,
with the base cuneate; male zone wholly within the lower spathe (above 800 m, Borneo) ................A. peltata
20a. Leaf blades with more or less conspicuous marginal vein only; lami nae various; male zone wholly or part-
ly within the lower spathe (mostly below 500 m, Borneo) ...............................................................................21
21. Primary lateral veins numerous, 8–10 on each side of midrib; secondar y venation striate; in peat swamp for-
est (peat swamp forest: Sarawak)................................................................................................... A. minuscula
21a. Primary lateral veins much fewer; secondary venation clearly colocasioid, but not forming interprimar y
collective veins ..................................................................................................................................................22
22. Leaf blades thickly coriaceous to subsucculent; male zone of spadix within lower spathe Chamber .........23
22a. Leaf blades thinly coriaceous or sub-membranous; male zone only partly included .................................24
23. Leaf laminae broadly ovato-elliptic, adaxially pale matt grey, abaxially greenish whitewith conspicuous
deep red axillar y glands abaxially; petioles puber ulent; fruiting spathe magenta (Kapit, evergreen upper hill
forest on sandstones above 500 m asl) ..................................................................................................... A. chaii
23a. Leaf blade narrowly elliptic to ovate to narrowly obovate, mid green above, slightly paler with inconspicu-
ous pale green axillary glands; petioles glabrous fruiting spathe pale green (NW Borneo, kerangas below 500
m) .........................................................................................................................................................A. beccarii
24. Laminae ascending (adult plants) to weakly spreading ( juveniles), thinly and weakly coriaceous, lustrous
deep pur ple-black; petioles minutely puberulent; infructescences deexed (sandstone: Kapit) ... A. infernalis
24a. Laminae pendent to weak ly spreading (adult & juvenile plants), thinly, stify cor iaceous; never deep pur-
ple-black; petioles glabrous; infructescences erect (limestones) .....................................................................25
25. Leaf blades dark green throughout and somewhat darker around midveins; inorescences to ca. 6 together;
stigma mostly tri-lobed (limestones: Gua Niah) .................................................................................A. venusta
25a. Leaf blades grey-green and dark blue-green arou nd veins; inorescences solitar y to paired; stigma mostly
bi-lobed (limestones: SE Sarawak) ......................................................................................................A. reversa
Alocasia baginda may be inserted in the Key in Boyce (2007) after modications to couplet 16: