AMORPHOPHALLUS KHAMMOUANENSIS
PROTOLOGUE: Amorphophallus khammouanensis A.Galloway, published in Aroideana 38: 6 (2015).
Amorphophallus khammouanensis A.Galloway sp. nov. Type: from a plant cultivated by A. Galloway (orig. coll.: LAOS, Khammouane Province, in moist shaded areas, A. Galloway), 22 March 2012, Galloway AGA-2198-01-T (holotype, QBG, spirit collection).
DISTRIBUTION: Laos: Laos.
DISTRIBUTION NOTE: Laos: Khammouane Province (only known from the type locality)².
SPECIES DESCRIPTION:
Tuber depressed globose, 8–10 cm in diam., 6–7 cm high, brown, no offset development. Leaf solitary; petiole 40–45 cm long, 3 cm in diam., smooth, olive green background with a pattern of dark green to black spots, sometimes also with superimposed scattered larger, irregular, pale greenish white spots, smooth, the junction of petiole to the rachises of lamina occasionally swelling to form an intercalary bulbil; lamina moderately dissected, up to 1 m wide, rachises winged distal from basal branching points; leaflets elongate-elliptic, 8–24 cm long, 4–8 cm in diam., acuminate, upper side green, lower side paler.²
INFLORESCENCE:
Inflorescence solitary, long peduncled; peduncle 30–38 cm long, 1 cm in diam., brownish green background with a pattern of dark gray to black spots, sometimes also with superimposed scattered larger, irregular, cream spots, smooth; spathe ovate, 15–18 cm long, 6.5–7.5 cm wide, outside bronzy green with very small black spots on lower half, inside green, base inside verrucate, top broadly acute. Spadix slightly shorter than spathe, 11–14 cm long, sessile; female zone cylindric, 2 cm long, 1.5 cm in diam., flowers congested; male zone subcylindric, slightly widening at the apex, 4.5 cm long, 1.75–2 cm in diam., flowers congested; appendix conical, oval-elliptic, or elongate fusiform, top obtuse, 6–7.5 cm long, 2–2.5 cm in diam., smooth, creamy white. Ovaries depressed, ca. 1.75 mm high, ca. 2.25 mm in diam., pale green, bilocular; style ca. 1 mm long, ca. 1 mm in diam., off white; stigma depressed, ca. 0.5 mm high, ca. 1.5 mm in diam., centrally depressed, verrucate, beige. Male flowers consisting of 2–4 stamens; stamens ca. 1.5 mm long, creamy-white; filaments 0.75 mm long, fused entirely, creamy white; anthers ca. 1.2 mm long, ca. 1.5 mm in diam., off white; pores apical, oval.²
ECOLOGY:
Found in moist shaded areas of Khammouane Province, Laos²
ETYMOLOGY:
The species epithet refers to the province in Laos where this species was found — Khammouane, with the Latin suffix-ensis marking the place of origin.²
NOTES:
1. Amorphophallus khammouanensis is closely allied to Amorphophallus croatii Hett. & A.Galloway (Laos) and Amorphophallus tonkinensis Engl. & Gehrm. (northern Vietnam) with which it shares the general leaf and inflorescence characteristics. Amorphophallus khammouanensis is larger in all aspects than Amorphophallus croatii and smaller in all aspects than Amorphophallus tonkinensis. Amorphophallus khammouanensis differs from Amorphophallus croatii by producing bright blue berries when ripe, while Amorphophallus croatii produces white berries with a faint bluish tint. It differs from Amorphophallus tonkinensis by having a smooth petiole, whereas Amorphophallus tonkinensis has raised blackish dots on its petiole. Also, the stamens are much longer in Amorphophallus tonkinensis.²
2. Amorphophallus khammouanensis tends to have an active growth cycle independent of the wet/dry seasons of its habitat, sometimes staying in leaf 12 to 18 months, whereas Amorphophallus croatii and Amorphophallus tonkinensis tend to have an active leaf growth cycle tied to the seasonal conditions of their respective habitats, usually 4 to 6 months. In pot culture, Amorphophallus khammouanensis prefers to remain potted in moist soil during dormancy.²
REFERENCES:
1. Plants of the World Online, Royal Botanic Gardens, Kew — Amorphophallus khammouanensis A.Galloway
2. Aroideana 38: 6 (2015) — protologue.
3. Alan Galloway — Amorphophallus khammouanensis, alangallowaybotanicals.com.
Additional photo by Bjørn Malkmus-Hussein