Mario Sousa (1940-2017), botanist. Chief of Mexico's Herbario Nacional from 1975 to 1985 and 1994 to 2003. Dr. Sousa, a devoted defender of herbaria and plant taxonomy, described some 100 species new to science, principally legumes. He was also instrumental in promoting botanical exploration throughout Mexico and Central America as a leader of expeditions and general editor of Flora Mesoamericana.
- Author abbreviation: M.Sousa