Italian cryptogamist from Bairo, near Turin, who trained at the Collegio Fascarini in Venice and the school of viniculture in Conegliano (1876 - 1879). He emigrated to Argentina where he was employed as an assistant to the natural science faculty at the University of Buenos Aires (1879) and later curator of the herbarium of the National Department of Agriculture and the first head of the herbarium of Museo de La Plata (LP). Spegazzini was appointed Professor of Botany, Phytopathology and Agrochemistry at the University of La Plata (1897-1912). He worked mainly with fungi, including fungal parasites and specialised in the Laboulbeniales. His collections are mainly from Argentina, but he also visited Chile, Brazil and Paraguay. He was botanist to the scientific expedition of Giacome Bove to Patagonia and Tierra del Fuego (1882) on behalf of the Argentine Government. Spegazzini bequeathed his house as a base for the Instituto de Botánica Carlos Spegazzini (LPS) where his mycological herbarium is held. Many taxa are named in his honour including the cactus Rebutia spegazziniana Backeb. and the orchid Oncidium spegazzinianum Schltr.