ALOCASIA MEGAWATIAE
ORIGINAL DESCRIPTION:
Alocasia megawatiae Yuzammi & A. Hay, sp. nov., Alocasia puber (Hassk.) Schott simulans sed planta robustiore, folii lobis posticis rotundis, tota inflorescentia mascula intra spatham inferiorem cylindroideam contenti differt.
Type: INDONESIA, Central Sulawesi, Mount Tinombala Natural Reserve, Desa Labono, Kecamatan Nondo, Kabupaten Toli-Toli, 2 Nov 2000, Yuzammi 40048 (Holotypus BO, isotypus NSW).
SYNONYMS: N/A
DISTRIBUTION: Indonesia; Sulawesi (Central)
CLIMATE: Tropical humid climate
Humidity is moderate throughout the year, ranging from 60% to 70%
Temperature is varies between the seasons - within the range of 48°F/9°C to 88°F/31°C during the day. Minimum temperatures never dip below 45°F/7°C
Rainy and humid season (October to May) and a dry season between June and October. The average annual rainfall is 1,200 mm
ECOLOGY: In shady lowland rain forest, near a river and in wet places with well drained soil , ca. 300 m alt.
SPECIES DESCRIPTION:
Massive subarborescent pachycaul herb ca. 2.5 m high or more. Stem erect to decumbent, to 25 cm in diam., to over 1 m long. Leaves several together, held almost horizontally; petiole ca. 1.5 m long, hairy, with small white glands scattered up to upper petiole sheath, light green, sometimes with red-purple vertical tiny lines, sheathing ca. Y:I from the base of petiole; wing of sheath out-rolled; blade cordatesagittate, 68-95 cm long, 55-72 cm wide, leathery, dark-green, glossy and glabrous adaxially, pale green and pubescent abaxially, with undulate margin; anterior lobe 54-75 cm long with apiculate tip ca. 1 cm long; anterior costa prominent on both surfaces, glabrous adaxially, pubescent abaxially; primary veins 7-9 on each side, prominent on both surfaces, diverging at 45°-60°, with conspicuous glands in their axils, glabrous adaxially, hairy abaxially; secondary veins flush with lamina adaxially, raised and somewhat pubescent abaxially; interprimary collective veins well-defined; submarginal vein ca. 3 mm from the margin; posterior lobes 30-36 cm long, rounded; posterior costae naked in the sinus for 3-4 cm
INFLORESCENCE:
Inflorescences clustered in the center of the leaf crown, up to 26 together; peduncle greenish, hairy, ca. 30 cm long, 1 cm diam., thickening slightly in fruit, erect, sometimes somewhat curved (but not declinate) after anthesis. Spathe ca. 17 cm long, somewhat constricted level with upper part of male zone of the spadix; lower spathe very elongate, somewhat cylindric, convolute, ca. 6 cm long, ivory with scattered reddish-purple spots concentrated near the junction of spathe and peduncle; limb boat-shaped, ca. 11 cm long, ivory, with the margins reddish-purple at the base only, greenish at tip, erect then fully reflexed at anthesis. Spadix terete, subcylindric, attenuate at the tip, slightly shorter than spathe, stipe ca. 2 mm; female zone ca. 2.5 cm long, ca. 1 cm diam.; pistils closely packed ; ovary sub-globose, yellowish-green, ca 0.2 mm long, unilocular, 3-5 ovules, with basal placenta ; style terete, ivory, 1-1.5 mm long; stigma yellowish, turning red purple in spirit, 2- 3-lobed , lobes rounded; sterile zone ca . 4 mm long, ca. 8 mm in diam., creamy, slightly narrower than the fertile zones; synandrodia in ca . 2 whorls, somewhat rounded to hexagonal, more or less flat-topped , ca. 1.5- 2 111m in diam.; male zone whitish, ca . 4 cm long, ca. 1 cm in diam. , terete, almost completely contained within the lower spathe chamber; synandria rhombo-hexagonal, 1. 5-2 mm in diam. ; thecae opening through apical pores not overtopped by synconnective; synconnective somewhat impressed; appendix pale orange, about as thick as male zone, slightly over half the length of the whole spadix, tapering to a pointed tip. Fruiting peduncle to ca. 40 cm long, erect; fruiting spathe ca . 9 cm long, ovoid , white with scattered elliptic horizontally aligned flecks, basipetally dehiscent and revolute revealing bright red berries (Fig. 1)
Infructescences showing the central clustered flowering habit
VARIEGATED FORMS: N/A
ETYMOLOGY: The specific epithet acknowledges Ibu Megawati Sokarnoputri for her generous sponsorship of fieldwork in Sulawesi and other places in Indonesia. Her awareness of the value and the loss of biodiversity in Indonesia greatly encourages us and our institutions to continue the work of exploring Indonesia’s plant life, generating and disseminating information and educating the community about it and working towards its conservation
NOTES: Alocasia megawatiae differs from Alocasia puber to which it is the most similar of the species in this group, in having the posterior lobes rounded, the lower spathe chamber subcylindric and elongate, the male zone almost completely within the lower spathe chamber and almost always cylindric, appendix not narrow at the base. Alocasia puber has the posterior lobes usually acute, the lower spathe chamber more or less ovoid and relatively shorter, the male zone half within and half exserted from the lower spathe chamber and somewhat attenuate, and the appendix narrowed at the base. Alocasia megawatiae differs from Alocasia sarawakensis in that the former has the leaf blade, which is held horizontally, hairy in both juvenile and adult plants, the stipe of the spadix is short, ca. 2 mm, the female zone is almost cylindric, and the male zone is almost entirely within the lower spathe chamber. The latter species has the leaf blade held erect, hairy in juvenile plant and usually glabrous in adult plants, stipe quite long, ca . 5 mm, female zone wide at base and tape ring toward the upper part, male zone only partly with in the lower spathe chamber.
Philippine Alocasia maquilingensis differs from A. megawatiae in having a smaller inflorescence with an ovoid lower spathe chamber from which the male zone is almost completely exserted. The senior author found in the field that this species occurs in shady places in the forest, some times in almost complete shade . On the other hand, both Alocasia puber and Alocasia sarawakensis are found in open areas. The leaf blades of Alocasia megawatiae are held more or less horizontally, whereas they te nd to be held vertically in Alocasia puber and Alocasia sarawakensis. This may be a plastic response to the shady conditions in which the plants were found. In addition, it was found that the small bulbils borne on short stolons that characterize many Alocasia species, including Alocasia puber and Alocasia sarawakensis, seem to be absent from Alocasia megawatiae.
CULTIVARS: N/A
HYBRIDS: N/A
