Thibaudia retusifolia.  A: habit, with close-up of retuse leaf tip.  B: flower, with close-up of circular glands on calyx limb.  C: longitudinal section of corolla showing position of stamens and close-up of corolla lobes within.  D: stamens, side, front, and back views (Argent s.n., RBGE acc. no. 762356, type).  Reproduced from Flora of Ecuador 54: 315, fig. 20.  1996.