A tribute to Philippe Clerc: an eminent and multitalented lichenologist in Switzerland

Philippe Clerc was born on April 26, 1955, in Lausanne, Switzerland. He was as an undergraduate at the University of Geneva when he stumbled upon an article in the newspaper Tribune of Geneva about lichens and air pollution that first sparked his interest in lichens. To learn more, he went to Professor G. Turian, who was cited in the article and who loaned him a few books and a microscope, saying ‘First you have to know the species’. So a lichen taxonomist was born! His first academic work dealt with the application of lichens as bioindicators of air pollution in the Wallis region of Switzerland (Clerc & Roh 1979a, b). He obtained his master’s degree in Biology under Prof. Turian’s supervision in 1979. Philippe found his career path through the opportunity to work as a research assistant in the Department of Cryptogamy at the University of Bern under Prof. Klaus Ammann. The Eduard Frey (1888–1974) lichen collection had been acquired recently by the University and, in this collection, Philippe started to study the genus Usnea (the popular ‘old man’s beard’ lichen), which would become his main scientific interest for the next four decades. His first step was to visit Lublin (Poland) to study the collection of the Polish botanist and lichenologist, Józef Motyka (1900–1984), who had published a world monograph of the genus (Motyka 1936–38). The taxonomy and classification of Usnea appeared chaotic at that time and the genus was renowned as one of the most difficult to identify to species level due to its wide phenotypic plasticity and seeming over-abundance of names (as many as 1243). As Philippe later reflected: ‘the first two years of my thesis were completely in the shadows’, but he persisted and gradually dismantled and refined the taxonomy of Usnea. His first publications about the genus were soon published (Clerc 1984a, b) and, at the same time, he also obtained his secondary education certificate (Biology section, under Prof. M. Villard). He was awarded his PhD − ‘Taxonomy and systematics of the genus Usnea in Europe – Preliminary studies towards a monograph’ − in 1986 under the supervision of Professor K. Ammann. After acquiring his doctorate, he moved with his family to the USA to take up a Postdoctoral Research Fellowship at Duke University (North Carolina, USA) under Professors William L. Culberson and Rytas Vilgalys. This was an opportunity to study molecular biology and he became a pioneer in the molecular systematics of Parmeliaceae (1990–1993). He spent 15 months there (1988−1989). Returning to Bern, he started his career, funded by a National Foundation Research Fellowship, which enabled him to continue his project on the molecular systematics of the Parmeliaceae s.l. (lichenized Ascomycetes) that he began during his tenure as a post-doctoral researcher. The molecular era in the classification of lichens was just beginning, and this enabled the elucidation of the biological nature of lichen chimeras (or photosymbiodemes). It was established that the mycobiont in a chimera is only one species (not two as previously believed) and that the different vegetative morphology is determined by the associated photobiont (Armaleo & Clerc 1991, 1995) (Fig. 2B). He moved with his grant to Geneva in 1991 and, with Jean-François Manen (Geneva University), helped to establish the first molecular laboratory at the Conservatoire et Jardin botaniques de Genève. In 1993, Philippe was appointed to curator position at Conservatoire et Jardin botaniques in the City of Geneva (CJBG), at that time directed by Rodolphe Spichiger, where he has remained for the remainder of his working life. Geneva had a strong lichen tradition and one of the world’s most important lichen herbaria, thanks to the efforts of Johannes Müller (known as Müller Argoviensis), one of the most influential lichenologists of the 19th century. Müller had been a greatly respected Professor of Botany at the University of Geneva for 18 years and the 1 Conservatoire et Jardin botaniques de la Ville de Genève, 1 ch. de l’Impératrice, 1292 Chambésy/GE, Switzerland 2 Instituto de Investigaciones Biológicas y Tecnológicas IIBYT, Córdoba, Argentina 3 Instituto de Investigaciones en Ingeniería, Universidad de Costa Rica, San Pedro de Montes de Oca, 11501, Costa Rica 4 Dept. of Molecular Biology and Biotechnology, University of Dar es Salaam (UDSM), Tanzania 5 Dept. of Organismal Biology, Uppsala University, Sweden 6 Tasmanian Herbarium, Tasmanian Museum & Art Gallery, PO Box 5058, UTAS LPO, Sandy Bay, Tasmania 7005, Australia * Corresponding author e-mail: alice_gerlach @yahoo.com.br ISSN 2544-7459 (print) ISSN 2657-5000 (online) Plant and Fungal Systematics 65(2): 240–246, 2020 DOI: https://doi.org/10.35535/pfsyst-2020-0020