John W. Sheard's life-time work on the genus Rinodina in North America has now reached fruition in a monumental monograph published by the NRC Research Press. As a young English lichenologist, John started the project in 1967 as a postdoctoral fellow under Ernie Brodo's guidance at the National Museum in Ottawa. Subsequently he obtained a professorial position at the University of Saskatchewan, where he has continued his research on the group to the present time. Over the years drafts of keys were widely circulated and extensive collaborations were developed, particularly with other researchers at the University of Graz.
Overall the monograph covers 96 species, representing about one third of all the Rinodina species known world-wide. Five species are described as new to science, and one new combination is made. Good nomenclatural solutions for several species previously identified as problematic are proposed, and 30 previously described species are placed in synonymy. Ten species are newly recognized for North America, and 36 (37%) are currently considered endemic to North America.
Rinodina is circumscribed herein in the traditional sense of having brown, mostly 1-septate ascospores in apothecia with a thalline exciple (lecanorine apothecia), although, based on cladistic studies, it is acknowledged that the genus is paraphyletic. Subsequent molecular studies have helped to resolve some taxonomic issues and have confirmed the paraphyletic nature of the genus. But none of these recent investigations have elucidated an alternative approach to the taxonomy that is congruent with conventional characters. Accordingly, the genus as treated herein is the appropriate choice at this point in time.
The monograph has all the elements that one would expect and more. The characters investigated are discussed at length with particular emphasis on the 13 spore types recognized by Dr. Sheard. New information on chemical metabolites occurring in nearly half of the species is presented with assistance from Prof. J.A. Elix. The circumscription of the genus is discussed in some detail, and it is formally described. The useful key to species is divided into three groups based on substratum and the traditional dichotomous approach is utilized with helpful back-references given parenthically. Species descriptions are extensive, often covering two pages or more, and they include the thallus, apothecia, apothecial anatomy, ascospores, pycnidia (if seen), chemistry, substratum and ecology, distribution and substantial notes. Excellent representative photographs of ascospores for each species are provided as well as distribution maps. The lists of specimens examined is limited to collections from the US northward, but the distribution maps also document Rinodina occurrences in Mexico (17 species), the Caribbean (2 species) and South America (1 species). The species descriptions are followed by additional sections on 1) taxa excluded from North America, 2) species not studied, 3) species groups within the genus, 4) substratum and ecology, 5) phytogeography, 6) summary discussion, 7) glossary, 8) references, and 9) an index.
The phytogeography section is of particular interest, as it goes well beyond a consideration of species by political subdivisions or floristic elements. From an evolutionary perspective the potential origin of some species is traced as far back as the middle Triassic.
The most unfortunate challenge faced by Dr. Sheard was beyond his control – namely the lack of any specimens of six species described by Bouly de Lesdain from New Mexico based on the Arsène Brouard collections, which were recently rediscovered at the now defunct College of Santa Fe. Apparently the types were retained by Bouly de Lesdain at Dunkirk and destroyed in the early days of World War II, as they do not appear to occur in the Brouard collections now housed at ASU and UNM.
Overall this is a monograph of the first class. Any North American lichenologist will need to consult it often. In addition, lichenologists from other continents will find much useful information concerning this large genus.
