Eucosia species

Suetsugu, Kenji & Hsu, Tian Chuan, 2021, Taxonomic notes on the genus Eucosia (Orchidaceae) in Japan and Taiwan, Phytotaxa 520 (2), pp. 215-224 : 221

Key to the Eucosia species in Japan and Taiwan:

1. Leaves subleathery, ±stiff, broadly cuneate to rounded at base, 3-veined, main lateral veins obviously closer to margins; stipes 2–4 cm long ....................................................................................................................................................................... E. longirostrata

- Leaves membranous to papery, soft-textured, rounded to subcordate at base, margin usually ±undulate, 3- or 5-veined, if 3-veined then main lateral veins ±medial between midrib and margins; stipes 1–2 cm long...........................................................................2

2. Sepals 12–15 mm long; rostellum well developed; leaves adaxially dull greyish green, usually with dark green reticulate venation ............................................................................................................................................................................... E. cordata

- Sepals 7–9 mm long; rostellum absent; leaves adaxially glossy pale green, without conspicuous reticulate venation....................... .............................................................................................................................................................................................. E. carnea