Aeginetia, Linnaeus, 1753

Nuraliev, Maxim S., Pham, Van The, Nguyen, Van Canh & Parnell, John A. N., 2023, Sorting out Aeginetia (Orobanchaceae) in Indochina: A. sessilis is a synonym of A. acaulis, Phytotaxa 597 (4), pp. 269-279 : 277

Key to the species of Aeginetia in Cambodia, Laos, Thailand and Vietnam

(partly based on Zhang & Tzvelev 1998, Parnell 2001, 2008)

The key includes two morphs of A. acaulis in order to reflect the known morphological variation of this species and to isolate the relevant material if corresponding infraspecific taxa appear.

1. Pedicel ca. 10 cm long or longer; corolla maroon to purple (occasionally nearly white) or uniformly yellow.................................2

- Pedicel shorter than 10 cm (rarely up to 14.5 cm long), or flower sessile; corolla colour variable, usually with some red to purple hue, throat and center of lower lip often yellow (corolla never uniformly yellow) ...........................................................................3

2. Pedicel with 2 bracteoles near base; corolla uniformly bright yellow; corolla lobes broadly spreading, with dentate margin ........... ..................................................................................................................................................................................... Aeginetia flava

- Pedicel ebracteolate; corolla maroon or purple, occasionally almost entirely white; corolla lobes erect to weakly spreading, with entire to subentire margin.......................................................................................................................................... Aeginetia indica

3. Flower distinctly pedicellate, pedicel ca. 1.5–10(14.5) cm long.................................................... Aeginetia acaulis (typical morph)

- Flower shortly pedicellate to subsessile or sessile (seemingly sessile in general view of plant), pedicel up to ca. 0.7 cm long......... ................................................................................................................. Aeginetia acaulis (the morph corresponding to A. sessilis )