Rolf Singer (1906-1994)

Rolf Singer was one of the most influential figures in the history of mycology. In this part, we will try to synthesize the impact that Rolf Singer had on our knowledge of fungi. We refer readers to two interesting and informative works written by Martha Singer, his wife and companion of 60 years for additional information on his life (M. Singer, 1979, 1984). Several memorials on Rolf Singer also have been published (e.g., Mueller, 1994, 1995; M. Singer, 1994). These papers provide the historical backdrop to the discussions presented below.

While the bulk of Singer's papers dealt with the systematics of Agaricales and related taxa, he also profoundly influenced our knowledge of mycogeography, fungal ecology, and ethnomycology. Contributions to these four topics make up the vast majority of his 440 papers and books. However, he also published on other topics including fossil fungi (Singer,1957e, 1958j, 1990f), polypores (Singer, 1941a, 1943d, 1944b), human pathogens (Singer, 1955g, 1958q), and mountaineering (Singer, 1942e, f). Singer's first five papers were published in 1922 when he was 16 years old. He continued publishing at this impressive pace for the next 70 years.

During his career, Singer held academic positions on three continents and traveled extensively throughout the Americas, Europe, and parts of Asia. He also made one trip to North Africa. A detailed itinerary of his collecting expeditions, along with a listing of the countries in which he undertook fieldwork, is given in Strack and Mueller (1997). These travels left a lasting impression on him and provided him with a unique perspective. He developed an unequaled worldwide knowledge of the Agaricales and this, coupled with his keen mind and sharp eye, made him uniquely qualified to influence mycology.

Systematics and Nomenclature

Singer is probably best known for his impact on the systematics and nomenclature of Agaricales and related taxa. His monumental The Agaricales in Modern Taxonomy (Singer, 1986a) has appeared in four editions and is almost universally used as the "accepted" classification of mushrooms and their relatives. His monographs and revisions are often the only modern treatment for many genera.

His role in documenting fungal biodiversity is also unequaled, and he revolutionized what we know about Agaricales in South and Central America. Seventy-four of the 230 genera included in the fourth edition of The Agaricales in Modern Taxonomy (Singer, 1986a) were proposed by Singer and his colleagues, nearly a third of the accepted genera. He also proposed genera in families not treated in The Agaricales in Modern Taxonomy bringing the total new genera to 86. Additionally, he published over 2460 specific and infraspecific epithets distributed in 222 genera. Type localities for these new taxa occur in 58 countries or possessions. However, 85% of them were originally described from the Americas with Argentina, Bolivia, Brazil, Chile, Colombia, Mexico, and the U.S.A. accounting for 75%. Holotypes of these new taxa are housed in 40 herbaria throughout the world. Most of the specimens, however, can be found in a relatively few herbaria. Wu et al. (1997) published an index to all of the genera, species, and infraspecific taxa described by Singer. This index includes information on the type specimen, place of deposition, and a literature citation for the type description.

Singer also influenced the systematics community through his work on botanical nomenclature. He attended most of the International Botanical Congresses since the 1950s and he was a long-standing member of the Nomenclature Committee. His publications on the subject ranged from proposals for conservation of names (e.g., Singer, 1946b, 1967g) to major discussions on the implications of rule changes (e.g., 1948e, 1950l, 1960g, 1965g, 1983d, 1984e, 1986b,f, 1987d).


Singer's contributions to our knowledge of the biogeography and ecology of fungi were also extremely significant. His publications in these areas were often the first, or among the first, investigations on the subject. He and his colleagues produced ground-breaking studies on the occurrence and importance of mycorrhizae in various forest types in temperate and tropical South America (e.g., Singer, 1959j, 1960k, 1963i, 1964g, 1971c, 1983f, 1989d). His work along the Amazon and Rio Negro in Brazil helped document the different forest types in the region, and the role of fungi in the health and functioning of these systems (1978e, 1984b, c, 1986c, 1988c). He also carried out one of the first detailed community analysis studies on mushrooms in the Americas (Singer, 1965i). While he published few papers dealing solely with biogeography (e.g., Singer, 1955h, 1967f, 1988f), he included information on biogeography in many of his monographs and regional treatments.

Ethnomycology and mushroom cultivation

Singer's mycological interests also included hallucinogenic and edible fungi. He played an active role in the identification of the hallucinogenic fungi used in Mexico, and in subsequent physiological, ecological, and cultural studies of these fungi (e.g., Singer, 1957f, 1958h, r). Other papers on hallucinogenic fungi include Singer, 1959h, 1960j, and 1978g. He also was active in the study of the cultivation and utilization of edible mushrooms (e.g., Singer, 1961g, 1964i, 1987a).

A summary of his publications, however, does not fully document the impact that Rolf Singer had on mycology. He was an active correspondent and he promptly responded to the numerous requests for assistance and information. Numerous mycologists also had the pleasurable and rewarding experience of working with him in the field, and he facilitated the research of many mycologists, botanists, and zoologists working in the Neotropics.  His presence in mycology will live on through the incredible legacy that he left for us. We hope that the contributions included in this volume will help current and future mycologists tap this wealth of information.

Literature Cited

Holmgren, P. K., N. H. Holmgren, and L. C. Barnett. 1990. Index Herbariorum. Part I: The Herbaria of the World, 8th ed. New York Botanical Garden, 693 pp.

Mueller, G. M. 1994. Rolf Singer, 1906-1994. Mycologia, 87: 144-147.

Mueller, G. M. 1995. Rolf Singer's mycological legacy. McIlvainea, 11 (2): 7-9.

Mueller, G. M., Q.-X. Wu, J. H. Ginns, and S. A. Redhead. 1997. The publications of Rolf Singer, pp.101-111. In G. M. Mueller and Q.-X. Wu, eds., Mycological contributions of Rolf Singer: Field itinerary, index to new taxa, and list of publications. Fieldiana, Botany: n.s.:38.

Singer, M. 1979. Glancing back. Beiheft Sydowia, 8: 14-25.

Singer, M. 1984. Mycologists and Other Taxa. J. Cramer, Braunschweig, Germany, 120 pp.

Singer, M. 1994. In memoriam Rolf Singer. McIlvainea, 11 (2): 4-6.

Strack, B. A. and G. M. Mueller. 1997. The field itinerary of Rolf Singer, pp.9-12. In G. M. Mueller and Q.-X. Wu, eds., Mycological contributions of Rolf Singer: Field itinerary, index to new taxa, and list of publications. Fieldiana, Botany: n.s.: 38.

Wu, Q.-X., G. M. Mueller, and C. L. Ovrebo. 1997. An index to genera, species and infraspecific taxa of Basidiomycete fungi described by Rolf Singer, pp. 13-99. In G. M. Mueller and Q.-X. Wu, eds., Mycological contributions of Rolf Singer: Field itinerary, index to new taxa, and list of publications. Fieldiana, Botany: n.s.: 38.