AMORPHOPHALLUS VARIABILIS

PROTOLOGUE: Amorphophallus variabilis Blume, published in Rumphia 1: 146 (1837).

Amorphophallus variabilis Blume, Rumphia 1: 146 (1837). Type: Rumphia 1 (1837) plate 35, 37h. Brachyspatha variabilis (Blume) Schott, Syn. Aroid. (1856) 35. Amorphophallus variabilis Blume var. immaculatus Hassk., Flora 25(2), Beibl. 1 (1842) 8 - type not designated.

SYNONYMS:

HOMOTYPIC SYNONYMS: Brachyspatha variabilis (Blume) Schott in Syn. Aroid.: 35 (1856)

HETEROTYPIC SYNONYMS: Amorphophallus variabilis var. cuspidifoliatus Engl. & Gehrm. in H.G.A.Engler (ed.), Pflanzenr., IV, 23C: 80 (1911) Amorphophallus variabilis var. immaculatus Hassk. in Flora 25(2, Beibl. 1): 8 (1842) Amorphophallus zeylanicus Engl. in Pflanzenr., IV, 23C: 80 (1911) Arum caeruleopunctatum Zipp. ex Kunth in Enum. Pl. 3: 33 (1841) Arum stercorarium Zipp. ex Kunth in Enum. Pl. 3: 33 (1841)

DISTRIBUTION: Jawa to Lesser Sunda Is., Philippines: Java, Lesser Sunda Islands, Philippines.

DISTRIBUTION NOTE: Indonesia: Java, Madura and the Kangean Islands.⁷.

SPECIES DESCRIPTION:

A seasonal herb. Tuber depressed-globose, about 8 cm high and 15 cm across, white, with numerous small spindle-shaped offsets 1-1.5 cm long. Leaf solitary or occasionally two; petiole about 120 cm long and 3.5 cm across at the base, smooth or slightly rough at the base, and extremely variable in colour - from entirely green through olive-green or greyish-green to dark brown, with rounded, oval or elongated blotches of dark green, white, greyish green and dark brown, and blackish dots. Lamina about 125 cm across, the primary main branches naked; leaflets elliptic to elliptic-lanceolate, 4-34 cm long and 2-12 cm wide, the tip acuminate to long-acuminate, mid green above and pale green beneath.⁷

INFLORESCENCE:

Inflorescence solitary; peduncle smooth, coloured as the petiole, 8-120 cm long and 0.4-3 cm across at the base. Spathe erect, elongate triangular, acute, slightly constricted at the level of the male zone, 6-23 cm long and 3-20 cm across; the lower spathe convolute, outside yellowish-green suffused brown at the margin with scattered whitish and dark brown spots, numerous tiny dark brown dots and pale reddish-brown lengthwise lines, inside pale yellowish-green to reddish-brown with small flattened yellow warts at the base; the limb erect then slightly reflexed, broadly triangular with an acute tip, as the lower spathe outside, ivory to pale green or pale reddish brown within. Spadix sessile, usually much longer than the spathe and about twice its length; female zone about 1 cm long, the pistils nearly globose, green and closely packed; ovary about 3 mm high and 2 mm across, green, two-chambered with a single ovule in each on a basal placenta; style about 0.5 mm long; stigma two-lobed, bright yellow. No sterile zone. Male zone cylindric, about 2 cm long - usually twice the length of the female zone - pale apricot; male flowers of two or three parts; anther dumbbell-shaped seen from above; stamen truncate, about 1 mm long and 1 mm across, the thecae opening by apical pores. Appendix pale yellow, at least twice the length of the male and female zones together, granular, tapering towards the tip. Fruit a bright orange-red berry with one or two seeds.⁷

ECOLOGY:

Found in teak forest, in Altingia forest, in disturbed forest and in village gardens, from near sea level to 700 m.⁷

PROPAGATION:

Our results with this species ranged from 51.6% with early September cuttings to 0% for mid-October cuttings.

ETYMOLOGY:

From Latin variabilis, “variable” or “changeable,” referring to the extraordinary variation in coloration and patterning seen within the species, particularly on the petiole and inflorescence. Individuals may range from entirely green to heavily mottled in green, brown, white, and grey, making variability itself one of the species’ most conspicuous characteristics.

NOTES:

1. ⚠ The type is a plate, not a specimen: Blume founded the name on his own figures in the Rumphia, plate 35 and plate 37h. Amorphophallus paeoniifolius is the only other species in the genus whose name rests on an engraving.²

2. It is a common plant in Java, and its variability is the point of it - petiole and peduncle colour and the size of the inflorescence all range widely.⁷

3. A variety was raised on that variability and later dropped. Hasskarl separated var. immaculatus in 1842 on petiole and peduncle colour; because those are precisely the characters the species is most plastic in, the modern reviser judged varieties no longer useful. Hasskarl said he had seen material, presumably a plant at Bogor, but none has been found.⁷

4. The spadix is usually about twice the length of the spathe, and the appendix alone is at least twice the male and female zones together.⁷

REFERENCES:

1. Plants of the World Online, Royal Botanic Gardens, Kew — Amorphophallus variabilis Blume

2. Rumphia 1: 146 (1837) — protologue.

3. Alan Galloway — Amorphophallus variabilis, alangallowaybotanicals.com.

4. Aroideana 19 (1996):P7 - 131

5. Propagation of Amorphophallus by Leaf Petiole Cuttings — Juniper Level Botanic Garden

6. iNaturalist: Amorphophallus variabilis

7. Amorphophallus Blume ex Decaisne (Araceae - Thomsonieae) in Java. Reinwardtia 13(1): 1-12 (2009)