Forty-five years of lichenology: a tribute to Emmanuël Sérusiaux

Emmanuël Sérusiaux was born in Dinant (Wallonia, Belgium) on October 3rd, 1953. He obtained his ‘license’ (master’s degree) in botany in 1975 and his doctorate in botanical sciences in 1982, both summa cum laude. In between the two courses of study he spent a year in 1976 at Harvard University (Massachusetts, USA) as a special student, based on a fellowship from Rotary International. He was awarded several distinctions, including the Prix Emile Laurent de l’Académie royale des sciences, des lettres et des beaux-arts de Belgique in 1986 and the Prix E. de Wildeman de la Société royale de botanique de Belgique in 1989. Emmanuël’s passion for lichens has always been accompanied by a vibrant interest in the conservation of nature. He has led two intertwined careers, one in the biological sciences and the other related to political aspects of nature conservation. He started his scientific career as a research associate for the FNRS (Fonds national de la recherche scientifique, Belgium, 1982–84), then as a research associate at the University of Liège (Belgium, 1984–86), before a first position as Deputy Chief of Staff to the Minister of Agriculture and Environment of Wallonia (1986–88). Then he returned to pursue his studies in lichenology as a research fellow (chercheur qualifié) for the FNRS (1988–99), before a second appointment as Chief of Staff to the Minister of Territory Development, Urbanism and Environment of Wallonia (1999–2004). He was then offered a faculty position at the University of Liège, in the Department of Biology, Ecology and Evolution (2004–19), at the rank of Professor and as head of the Plant Taxonomy and Conservation Biology unit, later renamed Evolution and Conservation Biology. To complete the perfect symmetry between his two careers, he completed a third term as Chief of Staff to the President-Minister of Wallonia (2017–19). Emmanuël retired from both positions in 2019. During his time as Professor at the University of Liège, Emmanuël founded the aCREA (Conseils et recherches en écologie appliquée), a consulting firm attached to the University. The centre aimed at integrating ecology into strategies for conservation and management of natural resources, biodiversity and landscapes, and focusing on analyses of the biological and landscape components of the environment, nature conservation (flora, fauna and ecosystems), management of natural resources (water, soil) and environments, territory development, environmental impact studies and landscape integration, and development of the living environment. Emmanuël has been much involved in the guidance and administration of science at the University, especially in aspects regarding the environment. He was President of Aquapole, a research centre for water-related sciences (2002–19), and Member of the Research Council of the University (2005–09) and of the Administrative Board of LEPUR (Centre de recherche sur la ville, le territoire et le milieu rural, 2004–19). Emmanuël has always been deeply involved in environmental conservation; he was concerned that students graduating with a master’s degree in biological sciences would not possess the skills required for field biologist positions. That is why he founded a specialized Master in Conservation Biology and Biodiversity Management programme, to enhance students’ competitiveness for positions in conservation biology. This master’s degree was created in 2014 and has become very successful, typically having 10–15 students pursuing it every year. The curriculum of this degree offers training in the identification of plants and animals, but also in GIS (geographical information system) and in environmental laws, preparing students for employment in agencies and organizations involved in environmental conservation. Emmanuël has also been very active in environmental matters outside of the University. He has been President of Espaces naturels d’Europe (1990–94), Réserves naturelles RNOB (1992–99) and the Administration Board of Natagora, the largest NGO dedicated to biodiversity and conservation in Wallonia, with over 100 staff, 1200 volunteers

Emmanuël Sérusiaux was born in Dinant (Wallonia, Belgium) on October 3 rd , 1953. He obtained his 'license' (master's degree) in botany in 1975 and his doctorate in botanical sciences in 1982, both summa cum laude. In between the two courses of study he spent a year in 1976 at Harvard University (Massachusetts, USA) as a special student, based on a fellowship from Rotary International. He was awarded several distinctions, including the Prix Emile Laurent de l'Académie royale des sciences, des lettres et des beaux-arts de Belgique in 1986 and the Prix E. de Wildeman de la Société royale de botanique de Belgique in 1989.
Emmanuël's passion for lichens has always been accompanied by a vibrant interest in the conservation of nature. He has led two intertwined careers, one in the biological sciences and the other related to political aspects of nature conservation. He started his scientific career as a research associate for the FNRS (Fonds national de la recherche scientifique, Belgium, 1982-84), then as a research associate at the University of Liège (Belgium, 1984-86), before a first position as Deputy Chief of Staff to the Minister of Agriculture and Environment of Wallonia (1986-88). Then he returned to pursue his studies in lichenology as a research fellow (chercheur qualifié) for the FNRS (1988-99), before a second appointment as Chief of Staff to the Minister of Territory Development, Urbanism and Environment of Wallonia (1999Wallonia ( -2004. He was then offered a faculty position at the University of Liège, in the Department of Biology, Ecology and Evolution (2004-19), at the rank of Professor and as head of the Plant Taxonomy and Conservation Biology unit, later renamed Evolution and Conservation Biology. To complete the perfect symmetry between his two careers, he completed a third term as Chief of Staff to the President-Minister of Wallonia (2017-19). Emmanuël retired from both positions in 2019.
During his time as Professor at the University of Liège, Emmanuël founded the aCREA (Conseils et recherches en écologie appliquée), a consulting firm attached to the University. The centre aimed at integrating ecology into strategies for conservation and management of natural resources, biodiversity and landscapes, and focusing on analyses of the biological and landscape components of the environment, nature conservation (flora, fauna and ecosystems), management of natural resources (water, soil) and environments, territory development, environmental impact studies and landscape integration, and development of the living environment.
Emmanuël has been much involved in the guidance and administration of science at the University, especially in aspects regarding the environment. He was President of Aquapole, a research centre for water-related sciences , and Member of the Research Council of the University (2005-09) and of the Administrative Board of LEPUR (Centre de recherche sur la ville, le territoire  et le milieu rural,  . Emmanuël has always been deeply involved in environmental conservation; he was concerned that students graduating with a master's degree in biological sciences would not possess the skills required for field biologist positions. That is why he founded a specialized Master in Conservation Biology and Biodiversity Management programme, to enhance students' competitiveness for positions in conservation biology. This master's degree was created in 2014 and has become very successful, typically having 10-15 students pursuing it every year. The curriculum of this degree offers training in the identification of plants and animals, but also in GIS (geographical information system) and in environmental laws, preparing students for employment in agencies and organizations involved in environmental conservation.
Emmanuël has also been very active in environmental matters outside of the University. He has been President of Espaces naturels d' Europe (1990-94), Réserves naturelles RNOB (1992-99) and the Administration Board of Natagora, the largest NGO dedicated to biodiversity and conservation in Wallonia, with over 100 staff, 1200 volunteers and 20,000 members . He was also President of the Société wallonne des eaux .
As Professor, Emmanuël has inspired several generations of students in a range of courses spanning Botany, Plant Systematics, Lichenology, Biogeography, Biodiversity, Evolutionary Biology and Conservation Biology. In particular, he has organized numerous field courses providing students with opportunities to experience biodiversity in situ. Over the years, Emmanuël has led such field courses in Tenerife (Canary Islands), Romania, Rwanda and France (Vosges, Alsace, Brittany).
Emmanuël has been a valued and influential mentor to students. He has always been very generous to and supportive of his master's and doctoral students, while giving them the freedom they have needed to develop their scientific independence. He successfully mentored many students, a number of whom have become well estab- Emmanuël has authored or co-authored no less than 145 papers related to lichens (a full list of his publications is appended below). His first publication devoted to lichens appeared in 1976, entitled 'Some foliicolous lichens from the Farlow Herbarium', followed in 1977 by a contribution to the genera Everniopsis, Normandina and Placopsis from Kivu ('Zaïre'), Rwanda and Burundi with Prof. J. Lambinon (1936Lambinon ( -2015 of the University of Liège (Belgium).
In the 1980s he treated other genera of macrolichens in East Africa, such as Coccocarpia, Lobaria, Stereocaulon and parmeliaceous lichens (Sérusiaux 1981, and he published on foliicolous lichens from various regions (Argentina, tropical Africa, France, southeastern United States) (de Foucault et al. 1982;De Sloover & Sérusiaux 1984;Sérusiaux & De Sloover 1986). During this period, Emmanuël also focused his work on unusual reproductive structures found in foliicolous lichens. He studied the nature and origin of campylidia in lichenized fungi ) and introduced the term 'goniocystangium' for a peculiar concave, cup-like structure producing diaspores (goniocysts) in several species of foliicolous Opegrapha (Sérusiaux 1985). Emmanuël published a first red list of macrolichens for the European Community in 1989 (available at http://hdl.handle.net/2268/138066) for the preparation of Directive 92/43/EEC on the conservation of natural habitats and of wild fauna and flora.
In the 1990s, he produced several contributions on foliicolous lichens from Western Europe and Macaronesia, describing, for example, the new genus Fellhaneropsis and several new species in the genera Byssoloma and Fellhanera (Sérusiaux 1993(Sérusiaux , 1996. He also continued working on tropical foliicolous taxa, reinstating the genus Eremothecella and describing several taxa having complex conidiomata (Lücking & Sérusiaux 1996Sérusiaux 1992Sérusiaux , 1995Sérusiaux & Lambinon 1994). He joined a collecting expedition to Papua New Guinea with his friends André Aptroot, Paul Diederich and Harrie Sipman, during which they collected almost 10,000 specimens. In their 'Lichens and lichenicolous fungi from New Guinea' (Aptroot et al. 1997) they provided an annotated list of species new for the country or otherwise interesting, and described six new genera and 89 new species.
In 2000, Emmanuël published, with his long-time colleague and friend Paul Diederich, 'The Lichens and Lichenicolous Fungi of Belgium and Luxembourg. An Annotated Checklist' (Diederich & Sérusiaux 2000), followed in 2004 by 'Les macrolichens de Belgique, du Luxembourg et du nord de la France. Clés de détermination' , which is the reference for identifying lichens in Belgium and Luxembourg. That same year, he co-authored a revision of the genus Strigula for Europe and Macaronesia (Roux et al. 2004).
In 2006, he began a fruitful collaboration with Eberhard Fischer and Dorothee Killmann (Universität Koblenz-Landau, Germany) to study lichens from tropical Africa and Madagascar, describing the new genus Nyungwea from Rwanda for a remarkable crustose corticolous lichen characterized by its goniocyst-producing stipes ; the new species N. pyneei described from Mauritius in this volume is a second species in the genus, differing by the absence of stipes). They described with one of us (Damien Ertz) two new species of basidiolichens from savanna soils in Rwanda, remarkable for their squamulose thallus with Multiclavula-like basidiomata (Fischer et al. 2007), which were later sequenced and recognized, along with a Neotropical species, as the new family Lepidostromataceae (Ertz et al. 2008). They discovered the new genus Savoronala, a Malmideaceae remarkable for its placodioid thallus with erect stipes apically producing sporodochia with conidia, each wrapping a single algal cell (Ertz et al. 2014). They also published a series of new species from various taxonomic groups (Archer et al. 2009;Ertz et al. 2010Ertz et al. , 2014Fischer et al. 2017;Lumbsch et al. 2011;Sérusiaux et al. 2009;Yeshitela et al. 2009), including a new species in the moss genus Jonesiobryum (Fischer et al. 2006).