Aristolochia subgenus Aristolochia section Diplolobus subsection Podanthemum, Klotzsch, 1859

Luu, Hong Truong, Nguyen, Tran Quoc Trung, Nguyen, Quoc Dat, Nguyen, Thanh Trung, Nguyen, Thanh Trung & Do, Truong Van, 2022, Aristolochia thotteaeformis, a distinct new species from southern Vietnam, Phytotaxa 547 (2), pp. 167-176 : 173

Key to the species of Aristolochia subgenus Aristolochia section Diplolobus subsection Podanthemum in Vietnam

1. Shrubs erect; young branches zig-zag ...................................................................................................................... A. thotteaeformis

- Lianas or twiners; young branches straight ........................................................................................................................................2

2. Leaf blade polymorphic; margin deeply or shallowly 3-lobed............................................................................................ A. pothieri

- Leaf blade uniform; margin entire......................................................................................................................................................3

3. Leaf venation loosely reticulate; inflorescences condensely many-flowered; bracteoles minute; seeds winged .......... A. acuminata

- Leaf venation closely foveolate-reticulate; inflorescences loosely 3–5-flowered; bracteoles ovate; seeds non-winged..................... .................................................................................................................................................................................. A. impressinervis