Portrait and signature of CLODOMIRO PICADO TWIGHT (1887–1944), known also as Clorito Picado. A Costa Rican biologist, he studied pharmacy at the National University of Costa Rica, but later specialized in zoology and botany at La Sorbonne, Paris, and received his PhD with a dissertation on bromeliaceae. Picado was a Latin American pioneer in toxicology. His studies of venomous snakes and his development of antivenom sera culminated with the publication of Poisonous serpents of Costa Rica: their venoms, antiophidic therapy (1931), which brought him international recognition. He also made significant contributions to microbiology, including the study of bacterial diseases in beans. In 2000, two physicians from the Costa Rican San Juan de Dios Hospital came across manuscripts by Picado describing experiments carried out between 1915 and 1927 in which he demonstrated the inhibitory action of Penicillinium sp. on Staphylococcus and Streptococcus strains (Fleming reached the same conclusion in 1928). In addition to academic publications, he wrote popular science books, including one entitled Nuestra microbiología doméstica (Our household microbiology). He is considered a national hero and has been honored in his home country by a research center and a scientific award that bear his name.