Development of carpels and ovules in Psychotria carthagenensis (Psychotrieae) and Rudgea macrophylla (Palicoureeae) (Rubioideae, Rubiaceae)

► Embryological characters in Rubiaceae are diagnostic to understand relationships between taxa. ► Variations are scarce in sporo- and gametogenesis, but have significant importance in the carpel and ovule ontogeny. ► From evolutionary diagrams based on variations in ovule ontogeny of Rubiaceae a new type is here proposed - Psychotria type.