I did not notice any latex nor tri-foliolate leaves. All Cestrums seem to have tubular flowers with shorter petals than this one. Any other suggestion ?
Photos were taken in Michoacan, between Angangueo and Tlalpujahua, 19°32'N 100°23'W, near a marsh. Certainly not a Rubiaceae because of the alternate leaves and superior ovary ... Fresh leaves had a typical odor reminding that of Clerodendron.