Teuvo ("Ted") Tapio Ahti (born 14 June 1934) is a Finnish botanist and lichenologist who has made significant contributions to the taxonomy and biogeography of lichens.
Ahti was born in Helsinki on 14 June 1934 and spent his childhood summers in Asikkala, South Häme, where he learned to identify edible mushrooms.
His introduction to lichenology came through a classmate whose brother was married to the daughter of renowned lichenologist Veli Räsänen; during their joint birdwatching excursions in Helsinki, this friend shared his knowledge of lichens with Ahti.
He documented these early professional experiences in his first publication, an article in Molekyyli, a natural history magazine for young people.
He continued this forest inventory work in 1953, gaining practical experience in field biology before beginning his university studies.
[3] Ahti started developing an interest in botany at the age of 15, when he worked on a class project involving collecting 100 species of plants.
Known as a specialist of the Cladoniaceae, he wrote a monograph on this subject for the journal series Flora Neotropica, which reviewer William Culberson called "the long-awaited fulfillment of an old promise by one of the world's master taxonomists."
[6] Teuvo Ahti is married to botanist and vascular plant taxonomist Leena Hämet-Ahti, who he met while they were both completing their MSc degrees.
[3] While known primarily for his work on lichens, particularly the Cladoniaceae, his research interests encompassed a broader scope including ecology, vegetation studies, floristics, macro- and microfungi, lichenicolous fungi, bryophytes, phanerogams, and phytogeography.
His fieldwork has extended to all continents except Antarctica, conducting both specific research projects and participating in field meetings and congresses.
[3] A significant contribution to the field was his editorial work on William Nylander's lichenological papers, which he compiled into a six-volume series.
[7] In 2011, Ahti, along with co-authors Soili Stenroos [fi], Katileena Lohtander, and Leena Myllys, won the Tieto-Finlandia Award for their non-fiction work Suomen jäkäläopas ("Finnish lichen guide").
This tribute included a Laudatio ("in praise of") written by Orvo Vitikainen, Irwin Brodo, and Trevor Goward chronicling his career achievements, followed by ten scientific papers from colleagues worldwide covering diverse aspects of lichenology.
The special issue reflected both Ahti's primary research interests and his ability to foster international scientific collaboration throughout his career.