Key to Hanguana (Hanguanaceae) in Borneo

Adapted from Mohd Fahmi et al. (2012), and Hroneš et al. (2021)

1. Plants of open habitats (banks of large rivers, margins of freshwater bodies); colonial helophytes with massive, foliaceous stolons; seeds shallowly cupuliform ................................................................................................................................... H. anthelminthica

1. Plants of closed-canopy forests (lowland to montane rainforests, kerangas); clump-forming mesophytes lacking stolons; seeds bowl-shaped or globose with wedge-shaped ostiole .......................................................................................................................... 2

2. Leaf blade corrugated................................................................................................................................................................. H. loi

2. Leaf blade flat..................................................................................................................................................................................... 3

3. Leaf lamina linear-lanceolate to very narrowly elliptic; fruits weakly 3-lobed, ripening medium pink to magenta ......................... 4

3. Leaf lamina elliptic, broadly lanceolate, oblanceolate to elliptic; fruits variable but never 3-lobed, ripening pale yellow, red or black ................................................................................................................................................................................................... 5

4. All parts of the plant (sub)glabrous, without floccose indumentum; sterile bract 1; lowland Kerangas ca. 100 m elev..................... ........................................................................................................................................................................................ H. bakoensis

4. All parts of the plant covered by scattered and densely floccose hairs; sterile bract 2–3; mossy montane forest at 1200–1640 m elev .............................................................................................................................................................................. H. sitinurbayai

5. Small herb, up to 30 cm tall................................................................................................................................................................ 6

5. Medium to large herb, 40–150 cm tall ............................................................................................................................................... 7

6. Stem evenly covered by leaves; lamina elliptic; infructescence deflexed ............................................................................. H. nana

6. Stem apically with terminal crown of leaves; lamina broadly lanceolate; infructescence erect........................................ H. bogneri

7. Leaves 40–70 cm long; infructescence deflexed; ripe fruits red......................................................................................... H. deflexa

7. Leaves 60–100 cm long; infructescence erect; ripe fruits pale yellow or black ................................................................................ 8

8. Lamina oblanceolate to narrowly elliptic, with midrib round-raised abaxially; fruit lageniform, ripening black; stigma terminal, prominently stipitate.............................................................................................................................................................. H. major

8. Lamina elliptic, with midrib weakly impressed; fruit globose, ripening pale yellow; stigma distinctly oblique, sessile.................... ........................................................................................................................................................................................ H. karimatae