ALOCASIA FLABELLIFERA
ORIGINAL DESCRIPTION:
Ab Alocasia crassifolia (sic. old name for Alocasia alba)Engler petiolo eglanduloso, lamina minus coriacea, pedunculo breviore, spathae tubo albo differt; ab Alocasia macrorrhizos (L.) G. Don foliis paucioribus, lamina latissime ovatosagittata plus coriacea, nervis secundariis valde prominentis, spathae tubo albo, stigmate rotunde lobata differt.
Typus: Papua New Guinea, Madang Prov., North Coast road, in coconut plantation nr Biges River bridge, 5th February 1989, Hay- 4053 (NSW, holo).
The genus. Alocasia. (Araceae) in. Australasia. A. Hay | Blumea 35: 537 (1991)
SYNONYMS:
DISTRIBUTION: Papua New Guinea | Madang and Morobe Provinces only; also sighted in East Sepik, Central, and Western Province (in the latter apparently only in cultivation as an ornamental)
CLIMATE: Subtropical 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: Open wet disturbed sites
SPECIES DESCRIPTION:
Massive pachycaul; stem decumbent, rarely erect, to 80 cm long and 13 cm diam., more or less devoid of old leaf bases; leaves few, to 5 together; petiole to 140 cm long, sheathing in the lower c. 1/3-1/2; wings of sheath persistent and slightly recurved; lamina very broadly ovate-sagittate, held more or less vertically; anterior lobe to c. 60 cm long, c. 65 cm wide at base, slightly wider about one quarter of the way from the base, with c. 10 primary lateral veins diverging at c. 60 degrees; glands absent or very inconspicuous; secondary venation distinctly raised below, forming well defined interprimary collective veins; posterior lobes c. 30 cm long, rather rotund, overlapping, the costae naked in the sinus for c. 9 cm
INFLORESCENCE:
Inflorescences paired, on short peduncles amongst their leaf bases; spathe to c. 25 cm long, constricted about 1/4 of the way from the base, green in bud, the lower part soon becoming white just before anthesis, remaining white into early fruit, then becoming green; limb of spathe membranous, white to very pale greenish yellow, oblong, cowl-like, deliquescent and deciduous after anthesis; spadix slightly shorter than the spathe; female zone c. 3 cm long, 1.4 cm diam., with c. 60 pistils; ovaries very close-packed, rhomboid, greenish-white, unilocular, sometimes incompletely septate in the upper part; stigma on a distinct but very short style, yellow, (3- or) 4-lobed, the lobes rotund; ovules orthotropous; interstice of sterile organs short, about two whorls, barely constricted and usually below the constriction of the spathe; organs flat-topped, white, polygonal, close-packed; male zone c. 8 cm long, extending down into the cavity formed by the lower part of the spathe below the constriction, whitish, c. 1.3 cm diam.; synandria rhomboid to hexagonal, flat-topped, c. 2 mm diam., 4-7-staminate, with the anthers opening by lateral slits not reaching the top of the synandrium; appendix considerably exceeding half the spadix in length, slightly exceeding the male zone in diameterin the lower part, thence gradually tapering to a blunt point, composed of irregularly shaped, longitudinally orientated staminodia, white; fruit a red berry containing few seeds, exposed by the dehiscence of the lower spathe into longitudinally recurved segments; seeds several, c. 3.5 mm diam.,strophiolate.
VARIEGATED FORMS: N/A
ETYMOLOGY: From the Latin flabellum (fan) and fero (to carry)
NOTES:
Both this species and A. macrorrhizos are inadequately represented in herbarium collections of New Guinea plants. Herbarium material of Alocasia flabellifera is easily mistaken for Alocasia macrorrhizos. Krause (1920) cited some German New Guinea collections under his Alocasia indica (= Alocasia macrorrhizos) which are quite probably of this species. Although these have not been located at Berlin and are presumed destroyed, it seems likely that Alocasia flabellifera has not hitherto been recognised because of the similarity it bears in the herbarium to Alocasia macrorrhizos. In details of the spadix, the two species seem barely to differ, except in the form of the stigmas (which character, however, I have not been able to examine in more than a few specimens of either species), and in the proportionately slightly longer appendix of Alocasia flabellifera. The white lower spathe, which is also proportionally longer, is characteristic of this species. The two species are strikingly different, however, when the plants are seen together in entirety. There are fewer leaves per crown and the blades are much wider in Alocasia flabellifera, where the blades are more or less bluntly triangular and crowded in Alocasia macrorrhizos. The secondary venation is also a useful field character: it is very distinctly raised abaxially in Alocasia flabellifera and more or less flush with the lamina in Alocasia macrorrhizos. In the latter species the secondary venation does not form or forms very poorly defined interprimary collective veins, and the glands in the axils of the primary veins are conspicuous. Interestingly, there are other species of Alocasia closely allied to Alocasia macrorrhizos which seem barely to differ from it in spadix morphology. These include Alocasia portei, Alocasia crassifolia, and Alocasia odora. They form well defined geographical entities and are highly distinctive as entire plants. Engler placed the first in his Schizocasia owing to its dissected leaves. However, the latter two he knew from living material and was thus able to recognize their specific character, setting a precedent for here recognising Alocasia flabellifera at specific level. The alternative, of recognising the taxon at subspecific level, serves no more useful purpose, and would merely result, if consistency were to be achieved, in the loss of well-known binomials and their replacement with cumbersome subspecific trinomials.
Other specimens seen:
PAPUA NEW GUINEA. Madang Prov., nr Jaisaben, Hay 4030 (NSW); Morobe Prov., cult. Hort. Lae, Nicolson 1487 (K, L, LAE).
CULTIVARS: N/A
HYBRIDS: N/A
