Research

    Donald H. Pfister

pic_pfister_umbrella.jpg

         Pfister CV




Our lab group does research in the area of fungal biology in which we study taxonomy, life histories, and systematics – particularly of fungi in the Pezizomycetes, the Orbiliomycetes and recently in the Laboulbeniomycetes.  We are interested in the relationships among the members of these groups, their geographic distribution, and the associations of these fungi with other organisms.  Prof. Pfister has conducted research on topics related to documentation of collections and collectors of natural history specimens; particularly in relationship to the rich and varied collections at Harvard.  Our fieldwork ranges from collecting locally to southern South America.

Recent Publications

Laboulbeniomycetes: Intimate Fungal Associates of Arthropods

Haelewaters, D., Blackwell, M. & Pfister, D.H., Forthcoming. Laboulbeniomycetes: Intimate Fungal Associates of Arthropods. Annual Review of Entomology , 66 (13) , pp. 1-20. Publisher's VersionAbstract
Arthropod–fungus interactions involving the Laboulbeniomycetes have been pondered for several hundred years. Early studies of Laboulbeniomycetes faced several uncertainties. Were they parasitic worms, red algal relatives, or fungi? If they were fungi, to which group did they belong? What was the nature of their interactions with their arthropod hosts? The historical misperceptions resulted from the extraordinary morphological features of these oddly constructed ectoparasitic fungi. More recently, molecular phylogenetic studies, in combination with a better understanding of life histories, have clearly placed these fungi among filamentous Ascomycota (subphylum Pezizomycotina). Species discovery and research on the classification of the group continue today as arthropods, and especially insects, are routinely collected and examined for the presence of Laboulbeniomycetes. Newly armed with molecular methods, mycologists are poised to use Laboulbeniomycetes–insect associations as models for the study of a variety of basic evolutionary and ecological questions involving host–parasite relationships, modes of nutrient intake, population biology, host specificity, biological control, and invasion biology. Collaboration between mycologists and entomologists is essential to successfully advance knowledge of Laboulbeniomycetes and their intimate association with their hosts.
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Sareomycetes: more diverse than meets the eye

Mitchell, J.K., et al., 2021. Sareomycetes: more diverse than meets the eye. IMA Fungus , 12 (6). Publisher's VersionAbstract

Since its resurrection, the resinicolous discomycete genus Sarea has been accepted as containing two species, one with black apothecia and pycnidia, and one with orange. We investigate this hypothesis using three ribosomal (nuITS, nuLSU, mtSSU) regions from and morphological examination of 70 specimens collected primarily in Europe and North America. The results of our analyses support separation of the traditional Sarea difformis s.l. and Sarea resinae s.l. into two distinct genera, Sarea and ZythiaSarea as circumscribed is shown to comprise three phylospecies, with one corresponding to Sarea difformis s.s. and two, morphologically indistinguishable, corresponding to the newly combined Sarea coeloplataZythia is maintained as monotypic, containing only a genetically and morphologically variable Z. resinae. The new genus Atrozythia is erected for the new species A. klamathicaArthrographis lignicola is placed in this genus on molecular grounds, expanding the concept of Sareomycetes by inclusion of a previously unknown type of anamorph. Dating analyses using additional marker regions indicate the emergence of the Sareomycetes was roughly concurrent with the diversification of the genus Pinus, suggesting that this group of fungi emerged to exploit the newly-available resinous ecological niche supplied by Pinus or another, extinct group of conifers. Our phylogeographic studies also permitted us to study the introductions of these fungi to areas where they are not native, including Antarctica, Cape Verde, and New Zealand and are consistent with historical hypotheses of introduction.

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First collection of the asexual state of Trichaleurina javanica from nature and the placement of Kumanasamuha

Iturriaga, T., et al., 2021. First collection of the asexual state of Trichaleurina javanica from nature and the placement of Kumanasamuha. Asian Journal of Mycology , 4 (1) , pp. 19-28. Publisher's VersionAbstract
Ascomata of Trichaleurina javanica (Pezizomycetes) are encountered frequently in nature in tropical Asia. Its anamorphic state has been described previously as similar to Kumanasamuha. Our study describes the unusual anamorphic fungal specimen, MOZ170, collected from Gorongosa National Park, Mozambique. The fungal strain MOZ170 is identified using ribosomal DNA sequence data, its morphology is described, and morphological differences between the naturally growing anamorph and in vitro derived culture are compared. Phylogenetic placement of Kumanasamuha sundara was also determined using available data. The internal transcribed spacer (ITS) and partial large ribosomal subunit (LSU) were sequenced. Phylogenetic analyses of LSU supported MOZ170 as the anamorph of T. javanica, and revealed the proper placement of the type species of Kumanasamuha, i.e., K. sundara, within the Dothideomycetes. MOZ170 is characterized by its dark conidiophores growing in tufts, and conidia with curved, appressed crests and ridges. The comparison between naturally growing and in vitro grown cultures showed that the in vitro cultured anamorph had larger conidiogenous cells, larger conidia, and longer and more numerous lateral fertile branches compared to the fungus in nature. The present report represents the first anamorph collected from nature for this genus and one of the few natural collections of the anamorphic state within Chorioactidaceae with the exception of those of Desmazierella species.
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Notes on Trochila (Ascomycota, Leotiomycetes), with new species and combinations

Gómez-Zapata, P.A., et al., 2021. Notes on Trochila (Ascomycota, Leotiomycetes), with new species and combinations. MycoKeys , (78) , pp. 21-47.Abstract

Full Citation:

Gómez-Zapata P.A., D. Haelewaters, L. Quijada, D.H. Pfister and M.C. Aime. 2021. Notes on Trochila (Ascomycota, Leotiomycetes), with new species and combinations. MycoKeys 78: 21-47.

 

Studies of Trochila (Leotiomycetes, Helotiales, Cenangiaceae) are scarce. Here, we describe two new species based on molecular phylogenetic data and morphology. Trochila bostonensis was collected at the Boston Harbor Islands National Recreation Area, Massachusetts. It was found on the stem of Asclepias syriaca, representing the first report of any Trochila species from a plant host in the family Apocynaceae. Trochila urediniophila is associated with the uredinia of the rust fungus Cerotelium fici. It was discovered during a survey for rust hyperparasites conducted at the Arthur Fungarium, in a single sample from 1912 collected in Trinidad. Macro- and micromorphological descriptions, illustrations, and molecular phylogenetic analyses are presented. The two new species are placed in Trochila with high support in both our six-locus (SSUITSLSUrpb1rpb2tef1) and two-locus (ITSLSU) phylogenetic reconstructions. In addition, two species are combined in TrochilaTrochila colensoi (formerly placed in Pseudopeziza) and T. xishuangbanna (originally described as the only species in Calycellinopsis). This study reveals new host plant families, a new ecological strategy, and a new country record for the genus Trochila. Finally, our work emphasizes the importance of specimens deposited in biological collections such as fungaria.

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FungalTraits: a user-friendly traits database of fungi and fungus-like stramenopiles.

K.Abarenkov,, et al., 2021. FungalTraits: a user-friendly traits database of fungi and fungus-like stramenopiles. Fungal Diversity. Publisher's VersionAbstract
Põlme, S., K. Abarenkov, R.H. Nilsson, B.D .Lindahl, K.E. Clemmensen, H. Kauserud, N. Nguyen, R. Kjøller, S.T.  Bates, P. Baldrian, T.G. Frøslev, K. Adojaan, A. Vizzini, A.Suija, D.H. Pfister, et al. 2021. FungalTraits: a user-friendly traits database of fungi and fungus-like stramenopiles. Fungal Diversity.


The cryptic lifestyle of most fungi necessitates molecular identification of the guild in environmental studies. Over the past decades, rapid development and affordability of molecular tools have tremendously improved insights of the fungal diversity in all ecosystems and habitats. Yet, in spite of the progress of molecular methods, knowledge about functional properties of the fungal taxa is vague and interpretation of environmental studies in an ecologically meaningful manner remains challenging. In order to facilitate functional assignments and ecological interpretation of environmental studies we introduce a user friendly traits and character database FungalTraits operating at genus and species hypothesis levels. Combining the information from previous efforts such as FUNGuild and FunFun together with involvement of expert knowledge, we reannotated 10,210 and 151 fungal and Stramenopila genera, respectively. This resulted in a stand-alone spreadsheet dataset covering 17 lifestyle related traits of fungal and Stramenopila genera, designed for rapid functional assignments of environmental studies. In order to assign the trait states to fungal species hypotheses, the scientific community of experts manually categorised and assigned available trait information to 697,413 fungal ITS sequences. On the basis of those sequences we were able to summarise trait and host information into 92,623 fungal species hypotheses at 1% dissimilarity threshold.

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