Homalomena truncata
Evergreen herb to 0.85 m tall. Subterranean stem a rhizome, 3–5 ×1.5–2 cm, light brown outside. Cataphylls sheathing separately petiole and peduncle, green with faint pink mottling; petiole 45–85 ×1–2 cm, olive-green with pink mottling and dark carmine stripes; leaf blade pedate; leaflets 5, elliptic, to 25 × 9 cm, margins entire, apex acuminate, ending in an arista to 3 cm long; central leaflet base cuneate, with a petiolule to 4 cm long; lateral leaflets asymmetrical, decreasing a little in size outwards, base convex, shortly petiolulate, glossy green with barely impressed veins above, underside paler. Inflorescence more or less held at foliage level; peduncle to 0.75 m long, thin, green with dark green stripes; spathe tube slightly funnel-shaped, 6–7 × ca 1 cm at the base, pale green outside and white inside, white at the base; spathe mouth margins with broad, yellow-green auricles, ca 2 cm wide; spathe limb ovate, 8–9 × 3–4 cm in the middle, glossy yellow-green, acuminate, ending in a filiform tip to 2 cm long; spadix appendix slightly exserted from the tube, erect, subcylindrical, white-green, with a rounded, even or slightly rugose apex, ca 4 cm long × 3.5 mm wide, sessile, often with a few, short carmine or green bristles above the fertile part; fertile zone staminate or bisexual, ca 4 cm long; staminate flowers 3–4 androus, subsessile, anthers cream, carmine at the top; thecae dehiscing by an oblong pore; pistillate flowers densely arranged; ovaries ovoid, pale green; stigma subsessile, capitate. Infructescence unknown.
S. Myanmar (type), S. Thailand, N. Peninsular Malaysia.
Disturbed primary and secondary lowland evergreen forest; sometimes on limestone. Lowlands.
None recorded. Notes. — Homalomena truncata is immediately identifiable by the combination of truncate to hastate leaves and the spathes ca 3–3.5 cm long. Confusion with H. griffithii is possible although the smaller spathe (no more than 2.5 cm long) is readily diagnostic. The primary lateral veins of H. truncata dry markedly darker than the surrounding leaf blade; this is not so in H. griffithii. There are several names applied to these larger truncate-leaved Homalomena in Peninsular Malaysia and southern Thailand, and much needs to be studied before a stable taxonomy is achieved. I have taken a pragmatic approach and adopted the earliest applicable name. The name H. occulta has been haphazardly applied to any small Thai Homalomena with unconstricted spathes and weakly hastate to truncate leaves. Homalomena occulta is based upon a now lost Loureiro type, almost certainly from Hue, in central Vietnam; the name H. occulta cannot be applied with confidence to any known species and is best abandoned, the more so since a well established name, H. truncata, exists.