AMORPHOPHALLUS NATOLII
PROTOLOGUE: Amorphophallus natolii Hett., Wistuba, Amoroso, Medecilo & Claudel, published in Bot. Stud. (Taipei) 53: 415 (2012).
Amorphophallus natolii Hett., A.Wistuba, V.B.Amoroso, M. Medecilo & C.Claudel, spec. nov. TYPE: PHILIPPINES. Palawan, above El Nido town, on limestone cliffs overlooking the town, in small pockets or deep cracks with organic detritus (humus), alt. 175-450 m, 14 Dec 2010, V.B. Amoroso s.n. (holotype: Central Mindanao University Herbarium, nr. CMUH 00007678).
DISTRIBUTION: Philippines: Philippines.
DISTRIBUTION NOTE: Philippines: Palawan - limestone cliffs above the town of El Nido, 175-450 m; known only from the type locality.².
SPECIES DESCRIPTION:
Seasonally dormant tuberous geophyte. Tuber depressed globose, 3-8 cm in diam., 2.5-6 cm high, dark or mid brown, producing a few globose offsets, these loosely attached to the main tuber. Cataphylls uniformly rich pinkish brown. Leaf solitary; petiole 25-50 cm long, 1.3-2 cm in diam., smooth, entirely rich deep red, or green with an initial pinkish-purplish hue, the latter later turning all green, the lower part with tiny whitish or greenish speckles; lamina ca 70 cm wide, rhachises narrowly winged distal from the lowermost branchings; leaflets lanceolate, 4.5-15 cm long, 1.3-3.6 cm wide, narrowly acute-acuminate, upper surface dark green, lower surface pale green.²
INFLORESCENCE:
Inflorescence solitary, developing shortly (but slowly) directly after leaf senescence; peduncle 8-30 cm long, ca. 8 mm in diam., pinkish red, grading upwards to dark olive green, or uniformly olive green; spathe elongate-triangular, 11-16 cm long, 3-10 cm wide, base convolute, base and limb not separated by a constriction, limb erect, base outside dark olive green or dark pinkish red, upwards grading to dark pinkish red or pale pink sometimes with a few whitish, orbicular spots, inside pinkish red with either a few, scattered, shallow warts or more densely set, thicker warts, limb erect, outside pale green or pale pink, to the sides flushed with reddish pink, with or without dark veins, inside white with or without a pale greenish flush, slightly transparent, margin straight or slightly sinuous, slightly flushed pale pink, top acute. Spadix sessile, longer than spathe, 18-25 cm long; female zone cylindric, ca 1.6 cm long, 1.7 cm in diam., pistils adjacent, not congested; male zone cylindric or slightly obconical, ca 2.8 cm long, 1 cm in diam., stamens congested, with occasional hairlike staminodes in between; appendix elongate, thin, conical, 13.6-18.5 cm long, 0.9-1 cm in diam. at the base (excl. staminodes), gradually tapering to the acute tip, surface densely set with long, thin hair-like staminodes with swollen bases. Ovary depressed, orbicular in outline, 2 mm in diam., 1.3 mm high, bright pale green, unilocular, with an incomplete wall between the locules, ovules 1 or 2; style thick, 0.8-0.9 mm long, 1 mm in diam., bright pale green, bifurcating; stigma deeply or shallowly bi(-tri)lobed, elliptical or suborbicular in outline, 1 mm in diam., 0.3 mm thick, lobes hemispheric or conical, erect or diverging, sometimes of unequal length, minutely verruculate, whitish. Male flowers consisting of 3-4 stamens; stamens ca 1.5 mm long, filaments ca 0.9 mm long, fused, white; anthers ca 0.5 mm long, subrectangular in outline, 0.8-1.2 mm in diam., whitish, pinkish around the pores, connective broad, pores slit-like. Upper male flowers deformed and showing all transitional forms to the staminodes present on the appendix. Staminodes on appendix hair-like, 0.3-1.3 cm long, thin, perpendicular to the spadix axis, white, base swollen but less so in upper staminodes, to absent, elliptical in outline, verruculose, dirty pinkish or cream. Fruiting part elongate (seen only on pictures), berries crowded; berries orange red, top truncated, stigma persistent.²
ECOLOGY:
Found in exposed conditions, in small humus pockets or in deep cracks on a limestone hill; altitude: 175-450 m²
ETYMOLOGY:
Named after Basil Natoli and his family, who came upon the plant while roaming the country above El Nido on Palawan and photographed it; the pictures they sent on were enough for the species to be recognised as new.²
NOTES:
1. Diagnosis: the species differs from the others with densely hairy appendices - Amorphophallus hirtus, Amorphophallus longicomus and Amorphophallus pilosus - by its pinkish spathe colour, variously greenish to purplish in those three; from Amorphophallus hirtus and Amorphophallus longicomus by the absence of a distinct constriction of the spathe between base and limb; from Amorphophallus pilosus by lacking hair-like staminodes in the female zone of the spadix and by a subglobose rather than vertically elongate tuber; and from Amorphophallus longicomus additionally by its short style.²
2. Only three other species carry an erect, densely hairy, narrowly elongate conical appendix: Amorphophallus hirtus of Taiwan, Amorphophallus longicomus of Vietnam and Amorphophallus pilosus of Vietnam. All three hold spathe and spadix on a very long peduncle far outreaching the spathe, whereas in Amorphophallus natolii the peduncle may be shorter than or equal to the spathe, but may also be considerably longer (observations based on pictures only). The soft reddish pink to whitish pink of the inner spathe surface is near-unique in the genus; it is matched only on the outer surface of Amorphophallus bulbifer, Amorphophallus muelleri and Amorphophallus xiei, a closely knit group of triploids unrelated to these, and of Amorphophallus cicatricifer.²
3. Detailed observations by the first author of the protologue, Wilbert Hetterscheid, indicate that the hairs of the appendix are derived from functional anthers and are to be regarded as staminodes. Their resemblance to mammal skin may belong to a pollinator-deceit syndrome, or may work to stop pollinators climbing out of the spathe by way of the spadix during female anthesis. The scent during female flowering is reported as reminiscent of freshly cut wood (personal communication from W. Suarez in the Philippines, verified by Cyrille Claudel); the authors note that this is a new type of scent relative to the earlier surveys of Kite and Hetterscheid (1997) and Kite and colleagues (1998), and that it does not seem to support a cadaver-imitation syndrome.²
4. Amorphophallus natolii is one of four species restricted to Palawan and is assessed as critically endangered.⁴
5. In early March 2023, one of two flowering Amorphophallus natolii in one grower's collection produced a normal inflorescence, while the other produced an inflorescence with multiple spadices.⁵ The same grower reported very little pollen, or almost none, on the flowers, without saying whether this applied to both plants.⁶ Both remarks describe one grower's plants, not an established trait of Amorphophallus natolii.
HYBRIDS:
Amorphophallus natolii × Amorphophallus variabilis
REFERENCES:
1. Plants of the World Online, Royal Botanic Gardens, Kew — Amorphophallus natolii Hett., Wistuba, Amoroso, Medecilo & Claudel
2. Botanical Studies 53: 415 (2012) — protologue.
3. Alan Galloway — Amorphophallus natolii, alangallowaybotanicals.com.