Anthopterus molaui.  A: habit.  B: leaf base of lower surface showing circular glands.  C: flower bud.  D: flower at anthesis.  E: calyx in longitudinal and cross sections showing ovules and wings.  F: stamen showing dorsal, ventral, and lateral views (from Molau & Eriksen 2133, type).  Reproduced from Flora of Ecuador 54: 393, fig. 28.  1996.