The Wikipedia article of the day for August 23, 2021 is Edvard August Vainio.
Edvard August Vainio (1853–1929) was a Finnish lichenologist. His early works on the lichens of Lapland, his three-volume monograph on the lichen genus Cladonia, and, in particular, his study of the classification and form and structure of lichens in Brazil made Vainio renowned internationally. Vainio’s earliest works dealt with phytogeography—elucidating and enumerating flora and its distribution—in the Finnish language. In these publications he demonstrated an attention to detail and thoroughness that became characteristic of his later work. Vainio described about 1700 new taxa, and published more than 100 scientific works. He made significant scientific collections of lichens, and while a herbarium curator at the University of Helsinki and the University of Turku he catalogued and processed other collections from all over the world. He has been called the Father of Brazilian Lichenology and the Grand Old Man of Lichenology.