AMORPHOPHALLUS LAMBII
PROTOLOGUE: Amorphophallus lambii Mayo & Widjaja, published in Curtis's Botanical Magazine 184: 61, t. 852 (1982).
Amorphophallus lambii Mayo & Widjaja, sp. nov. Amorphophallus titano (Becc.) Becc. affinis sed statura minore, lamina spathae intus brunneo-purpurascenti ad basin pallide viridescenti nec plicato-costata nec margine dentata, tubo spathae intus verrucoso-rugoso, stigmatibus flavo-aurantiacis 2-3 lobatis, lobis subconoideis differt. — Type: Borneo, Sabah, Tenom, A. Lamb s.n. (K, holotype).
DISTRIBUTION: Borneo: Borneo.
DISTRIBUTION NOTE: East Malaysia: Sabah; Indonesia: Central Kalimantan⁴ iNaturalist: Sabah.
SPECIES DESCRIPTION:
Tuber depressed-globose, ca. 22 cm in diam., ca. 11 cm high, dirty white, no offset development. Leaf solitary; petiole to 200 cm long, ca. 8 cm in diam. (base), ground color whitish at the base, with a dense marbling of irregular green, confluent spots, their upper boundary darker and slightly raised, upwards a more continuous green color with scattered, large whitish or very pale greenish, oval spots with or without a darker green center; lamina to ca. 200 cm in diam.; leaflets elongate-elliptic, acuminate, 18-31 cm long, 7-10 cm in diam., upper side at first very glossy, later moderately glossy.⁴
INFLORESCENCE:
Inflorescence short-peduncled; peduncle as petiole, 8-10 cm long, 2.5-3.5 cm in diam., strongly lengthening in fruit to at least 60 cm; spathe campanulate, 28-45 cm long, ca. 34-52 cm in diam., limb spreading, margin inrolled, often with a few sharp edged, inward sinuses, base outside glossy, bright apple green with occasional, pale green, ring-like spots, inside dark maroon with an upper, dirty yellowish to pale greenish zone, continuing on the limb, limb outside green suffused with a blackish brown hue between the major veins, inside pale green with a few scattered, small, rounded, dark brown spots, to the margin pale to darker brown, base within verrucate and grooved. Spadix longer than spathe, sessile, 55-90(-150) cm long.⁴
ECOLOGY:
Found in shaded conditions in rubber plantations, cleared land, along river banks and in relict fragments of lowland rainforest surrounding hills, on rich alluvial soils; altitude: ca. 200 m⁴
ETYMOLOGY:
Named in honor of Anthony Lamb, a British botanist and horticulturist whose decades of work in Sabah contributed greatly to knowledge of the flora of northern Borneo. The Latinized epithet lambii means “of Lamb.” The geographical connection is particularly appropriate: Amorphophallus lambii is a Bornean species occurring in Sabah and Kalimantan.
NOTES:
1. Amorphophallus lambii resembles Amorphophallus hewittii but the latter has a long peduncle. Amorphophallus lambii has a rather long flowering period in cultivation, which may last over a week. It produces a distinct urine scent. The berries are eaten by bulbuls (Pycnonotus zeylanicus) as soon as they become ripe and turn red — infructescences are therefore always found to contain only orange, slightly unripe berries and a naked upper infructescence axis. It is a highly ornamental species both in leaf (very beautiful petiole) and in flower (highly contrasting colors between spathe exterior and interior).⁴
2. The species has close affinities with the Sumatran endemic Amorphophallus titanum, famous for the staggering proportions of its inflorescence. Amorphophallus lambii differs in its smaller size and details of spathe and spadix: the spreading limb of the spathe is brownish-purple within, shading basally to pale green, and lacks the prominent plicate ribbing and dentate margin of Amorphophallus titanum; the inner surface of the spathe tube is densely verrucose-rugose rather than smooth, and the stigmas are brilliant orange-yellow and distinctly 2- or 3-lobed. Shared characters of taxonomic significance include the long, slender styles, the 2-3-locular ovaries, the similar pollen, and a curious flange-like appendage on the funicle of the ovules.²
3. The plant figured in the protologue was collected at Tenom by Anthony Lamb, for whom the species is named, and reached Kew as two tubers in June 1980; it flowered for the first time on 11 February 1982, the odour at its peak being likened to a gas leak, old socks, rising damp or rotting prawns. Lamb noted that small beetles are attracted to the inflorescence during flowering, as has also been recorded for Amorphophallus titanum.²
REFERENCES:
1. Plants of the World Online, Royal Botanic Gardens, Kew — Amorphophallus lambii Mayo & Widjaja
2. Curtis's Botanical Magazine 184: 61, t. 852 (1982) — protologue.
3. Alan Galloway — Amorphophallus lambii, alangallowaybotanicals.com.
4. Aroideana 19 (1996):P7 - 131
5. iNaturalist: Amorphophallus lambii
6. A Review of the White-flowered Amorphophallus (Araceae: Thomsonieae) Species in Sarawak. (2010)
Additional photos by Furkon Muhammad