PREFACE Phylogenetic Revision of Taxonomic Concepts in the Hypocreales and Other Ascomycota

PREFACE Phylogenetic revision of taxonomic concepts in the Following the lead primarily initiated by Lombard et al. (Stud. Hypocreales and other Ascomycota - A tribute to Mycol. 66, 2010), this approach was followed here by Gräfenhan et Gary J. Samuels al. and Schroers et al. in their revisions of parts of Fusarium sensu Wollenweber and Acremonium by Summerbell et al. This volume of Studies in Mycology is something of a successor Option 2 – Teleomorph priority with anamorphic species epithets. to another issue of the same journal published a decade ago, Transfer of anamorphic epithets to teleomorph genera for species "Molecules, Morphology and Classification: Towards Monophyletic that lack known teleomorphs. New teleomorph generic names Genera in the Ascomycetes’ (vol. 45, edited by Seifert, Gams, are described when teleomorphs are discovered, irrespective of Crous & Samuels 2000). In that issue, the authors grappled with whether a previously described anamorph generic name exists. questions of integrating the new phylogenetic information derived This option maintains the primacy of teleomorph names at both from DNA sequencing into a classification system that was already complicated by the need to accommodate fungal pleomorphy. In the genus and species rank. It was exercised in part by Chaverri the intervening time, mycologists have become less tentative about et al. in their revision of Neonectria sensu lato, and the associated handling this complexity. The present volume continues the trend of anamorph genera Cylindrocarpon and Campylocarpon. applying multigene phylogenetics to generic and species concepts, extending the higher taxonomic level studies of the Assembling the Option 3 – Teleomorph priority with earlier anamorph species Fungal Tree of Life project into a more finely resolved realm. epithets not considered. Teleomorph genus and species name are both given priority. No There is another controversy brewing in the consciousness of attempt is made to revise anamorph genus or species names to contemporary ascomycete taxonomists, namely the issue of determine if older names exist. dual nomenclature, the practise that allows (and in some minds In common with Option 2, this option also maintains the demands) the use of two or more Latin binomials for one fungal primacy of teleomorph names and both the genus and species species, one for the teleomorph, if known, and the other(s) for the rank, but discounts known or unknown anamorph names from anamorph(s). This has been the focus of passionate discussion and consideration in the construction of binomials. This practise was debate in special sessions at the last three International Mycological followed by Hirooka et al. in their revision of Nectria cinnabarina, in Congresses. When we intiated this collection of papers in 2008, we parts of the revision of Neonectria by Chaverri et al., the revision of were not intending for a particular theme to arise. We knew the Plagiostoma by Meija et al. and the description of the new species papers would focus on Ascomycete systematics, and pay homage Guignardia korthalsellae by Sultan et al. Disregarding of anamorph to the craft of our honoree, Gary Samuels, i.e. an attention to names, however, does not always indicate a rejection of anamorph quality illustrations, complete descriptions, anamorph-teleomorph taxonomy per se; in the last example, there is no comprehensive connections, and species-level molecular phylogenetics. But revision of the anamorph genus Phyllosticta to enable the selection along the way, in one way or another, most of the authors found of possible earlier epithets for G. korthalsellae. themselves facing the concept of dual nomenclature, most of them trying to work around it in their own way. Option 4 – Teleotypification. Teleotypification of previously Although there is disagreement among mycologists about the anamorphic names (genus or species) to holomorphic status. need for a single name nomenclatural system, most would probably This recently implemented provision of the ICBN in the Vienna agree with the following statements: Code (Art. 59.7) allows the status of an originally anamorphic name to be converted to holomorphic status by epitypification of its type A. Taxonomists should try to minimise name changes. specimen with a teleomorphic specimen. This provision cannot B. If name changes are proposed, a stable nomenclature be used if an existing teleomorph is already named. As presently should result. described in the ICBN, it is unclear whether this status is conveyed C. Classifications and nomenclature should reflect only to the species in question or to the generic name if the type phylogeny to the extent that this is practical. species is teleotypified. D. If classifications and the resulting nomenclature reflect In this issue, this approach was followed by Réblová & phylogeny, taxonomic and nomenclatural stability will result. Seifert, who changed the originally hyphomycetous status of Sterigmatobotrys to holomorphic status by epitypification. The usual criticism of any taxonomic change, or change to nomenclatural rules, is that the changes will lead to chaos, with Option 5 – Single species names but allowing two genera per clade. confusion among users and a loss of credibility for the taxonomic Teleomorphic species are named in teleomorph genera and have endeavour as a whole. But our experience is that virtually all only teleomorph-typified epithets; anamorphs are unnamed or fungal taxonomists abide by the premises listed above, and it is referred to by their anamorph generic name. Anamorphic species disingenuous to suggest otherwise. are named in anamorph genera and have only anamorph-typified With Dual Nomenclature as the status quo, the authors of epithets. The result is that each species has a single name, but a papers in this issue have adopted five different interpretations of monophyletic clade may have one teleomorph and one anamorph One Fungus: One Name. name associated with it. This has often been referred to as cross reference Nomenclature, where anamorph species epithets are Option 1 – Strict priority. Strict application of priority of both generic dropped once the teleomorph is known, and anamorphs are then names and species epithets, irrespective of whether these names referred to only as Anamorph-genus-name of Teleomorph-genus were originally typified by anamorphic or teleomorphic elements. species epithet. Open access under CC BY-NC-ND license. This option is completely consistent with the requirements of the Seifert to teleotypify this species. Huhndorf & Miller wrestle with the present Code. In this issue, Põldmaa followed this practise in her phylogeny of genera in the Chaetosphaeriales, describing a new revision of tropical species of Hypocrea and related Cladobotryum species from New Zealand in the Helminthosphaeriaceae. Mejía anamorphs. et al. provide an account of the 25 accepted species of the genus Which of these options, or practises derived from these, might Plagiostoma (Gnomoniaceae, Diaporthales) of which eight are new ultimately be chosen to implement the concept of One Fungus : to science. Finally, Johnston et al. describe two new species on One Name remains for discussion amongst mycologists. We native New Zealand mistletoe in the dothideomycetous genera suggest that comparing options, including the maintenance of Dual Guignardia and Rosenscheldiella. Nomenclature, would be simplified if we could develop quantitative methods for evaluating each option objectively. Nomenclatural Reflections on the career of Gary Samuels Parsimony, a measure of the number of name changes needed to implement any particular system, should be an easy concept to Amy Rossman: I have known Gary for over 35 years since we define and to apply to each approach to single name nomenclature. first met on a collecting expedition in 1971 led by Dick Korf along Developing an algorithm for Nomenclatural Stability will probably with Don Pfister, Don Reynolds, and Kent Dumont. Gary was an be much more challenging, but the ability to compare the relative older student, two years ahead of me in graduate school, and he stability of particular kinds of nomenclatural changes should be a suggested that I tackle the long-spored Nectria-like fungi while he critical aspect of these discussions. polished off those with short spores. Thus, I had a thesis project. Throughout his career Gary has influenced other scientists About this issue inspiring them as he did me to work in many different groups of fungi. In truth, I think he would like to study all fungi, at least all of This issue is not about nomenclature, rather it is about the phylogeny the pyrenomycetes and their anamorphs. and taxonomy of several groups of Ascomycetes. The papers are Gary’s first job was in New Zealand where he relished the authored by collaborators and students of Gary Samuels, who diversity of the many local undescribed fungi and set to work has devoted his career to furthering the study of Ascomycetes publishing on species ranging from the “bizzaro” discomycetes all over the world. In parallel with his career, we have divided the to his beloved Hypocreales. During this period in New Zealand papers into two groups. The larger set of papers focuses on the he spent one-year with Emil Műller in Switzerland publishing on taxonomy of the Hypocreales, the order that Gary cut his teeth on the connection of teleomorphs with asexual states for many new as a graduate student and continued to study for his whole career. and unusual species. Throughout his career Gary collected fungi He couldn’t help dabbling though, and the second group of papers on field trips especially in the Neotropics and New Zealand, later concern a diversity of Ascomycete orders and families, mirroring in Asia. From these fresh collections he would isolate single the many other papers that Gary has written. ascospores using a micromanipulator in order to grow the fungus The section on the Hypocreales includes four long papers in culture often producing the asexual state. These cultures have revising generic and species concepts in the economically and served as the basis for many projects undertaken by his students biologically critical family, the Nectriaceae.

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