AMORPHOPHALLUS LUZONIENSIS
PROTOLOGUE: Amorphophallus luzoniensis Merr., published in Philipp. J. Sci., C 10: 289 (1915). The protologue is reproduced below.
DISTRIBUTION: Philippines (Luzon): Philippines.
DISTRIBUTION NOTE: Philippines: Luzon — Cagayan Province, along the Abulug River (the type gathering, Curran 19560 with Weber s.n., January 1912); reported also from Laguna, and the current checklist records occurrences on Luzon and Basilan³.
SPECIES DESCRIPTION:
Tubers depressed-globose, when dry about 2 cm in diameter, emitting many roots. Petioles slender, about 50 cm high; lamina umbraculiform, 3-partite, the segments pinnatisect, about 20 cm long, membranaceous, the ultimate segments oblong to oblong-ovate, caudate-acuminate, 5 to 9 cm long, nearly the same color on both surfaces or slightly paler beneath, the sinuses acute, extending almost or quite to the rachis.²
INFLORESCENCE:
Sheaths of the peduncles membranaceous, brown when dry, the outer ones oblong-lanceolate, 2 to 3 cm long, the inner ones lanceolate up to 10 cm in length; peduncles slender, up to 10 cm in length. Spathes purple, about 15 cm long, thin, the tube broad, about 6 cm long, the lamina ovate, slightly acute-acuminate or merely acute, about 6 cm wide. Spadix slender, cylindric, a little shorter than the spathe, the pistillate part about 2.5 cm long, 1 cm wide, the staminate part contiguous, about 3 cm long and 8 mm wide, the appendage slender, continuous, verruculose, caudate, at the base 5 mm in diameter or less, gradually narrowed upward, the entire spadix about 14 cm long. Pistillate flowers: Ovary depressed, about 1 mm long, 1.5 mm wide, 1-celled, 1-ovuled; style slender, about 3 mm long; stigma ovoid, entire, somewhat oblique, about 1 mm long. Staminate flowers crowded, mostly 2-androus, the anthers subglobose, 1 mm long, 1.5 mm wide, opening by two terminal slits.²
ECOLOGY:
A species growing in crevices of limestone ledges at low altitude²
ETYMOLOGY:
Named for Luzon, the Philippine island of the type locality, with the Latin suffix-ensis marking the place of origin; Merrill described the species in 1915.
NOTES:
1. A species growing in crevices of limestone ledges, quite different from any other known Philippine form. Apparently through its elongated styles allied to both Amorphophallus longistylus of the Andaman Islands and to Amorphophallus harmandii of Cambodia, but differing from both in many characters — at once distinguished from the former by its much smaller spathes, and from the latter by its larger spathes and relatively much longer spadices.²
2. Amorphophallus luzoniensis is a lost species: its designated holotype was destroyed during the Second World War, and the plant has not been verifiably recollected since. A survey of northwestern Luzon compared an unidentified Amorphophallus to it, but the spadix did not correspond⁴; the rediscovery of the lost type of Amorphophallus longispathaceus in 2020 has, however, offered hope that the identities of such species can still be resolved.³
3. A preliminary conservation status of Near Threatened has been proposed for the species in the current Philippine checklist.³
STORY:
STORY TITLE: The species the war took
Elmer Drew Merrill described Amorphophallus luzoniensis in 1915 from plants collected along the Abulug River in Cagayan, northern Luzon — a small species growing in crevices of limestone ledges, "quite different," he wrote, "from any other known Philippine form." Its slender, caudate appendix and long styles set it apart from everything else in the archipelago.
Then the Second World War came to Manila. The herbarium of the Bureau of Science, where Merrill's types were kept, was destroyed in 1945, and the holotype of Amorphophallus luzoniensis burned with it. The species entered taxonomic limbo: a published name, a good description, and no specimen to anchor them. It has not been verifiably recollected since.
There have been close calls. A recent survey of northwestern Luzon found an Amorphophallus reminiscent of the lost species, but its spadix did not correspond with Merrill's account, and the plant was left unnamed. Yet there is reason for hope: the type of Amorphophallus longispathaceus — another Philippine species whose specimens were presumed lost to the same war — turned up in New York in 2020 and solved a century-old identity puzzle. Somewhere in the limestone country of Cagayan, or in an overlooked herbarium folder, Amorphophallus luzoniensis is probably still waiting.
REFERENCES:
1. Plants of the World Online, Royal Botanic Gardens, Kew — Amorphophallus luzoniensis Merr.
2. Philipp. J. Sci., C 10: 289 (1915) — protologue.