Boesenbergia species

Lý, Ng ọc-Sâm, Cao, Ng ọc-Giang & Leong-Škorničková, Jana, 2025, Boesenbergia monophylla (Zingiberaceae: Zingibereae), a new species from Central Vietnam, Phytotaxa 694 (2), pp. 184-192 : 190

Key to Boesenbergia species in Vietnam (modified from Lý (2017a)

1. Leafy shoots monophyllous........................................................................................................................ Boesenbergia monophylla

- Leafy shoots with 3 or more leaves....................................................................................................................................................2

2. Spike condensed, clasped by leaf sheaths ..........................................................................................................................................3

- Spike elongated, exserted from leaf sheaths.......................................................................................................................................4

3. Anther crest present............................................................................................................................................................. B. rotunda

- Anther crest absent ............................................................................................................................................................ B. petiolata

4. Leaf base cordate; inflorescence radical and central................................................................................................... B. siphonantha

- Leaf base attenuate or cuneate; inflorescence always central ............................................................................................................ 5

5. Leaf blade broadly elliptic, abaxially sparsely hairy; labellum white with deep red band at the base, extending to upper third, apical reddish-pink; ovary sparsely pubescent.................................................................................................................. B. quangngaiensis

- Leaf blade somewhat ovate, glabrous on both sides; labellum white with various red patterns; ovary glabrous..............................6

6. Leaf blade ovate; petiole subsessile to ca. 2 cm long; ligules to 8 mm long; calyx 3-short toothed; labellum somewhat orbicular... ............................................................................................................................................................................................. B. parvula

- Leaf blade narrowly ovate (lanceolate); petiole 2–6.5(–10) cm long; ligules 15–25 mm long; calyx entire or 2-toothed; labellum bowl shaped (elliptic or ovate) ................................................................................................................................... B. xiphostachya