Studies in the Lasiosphaeriaceae. Monographs of two key genera and a family-level phylogeny

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Introduction and Objectives

This project is a comprehensive study of the Lasiosphaeriaceae (Fungi, Ascomycetes), the largest and least studied family in the order Sordariales. The order contains a number of economically important taxa including the model organisms Neurospora crassa Shear and Dodge and Sordaria fimicola (Rob. ex Desm.) Ces. and de Not. This project is designed to not only resolve systematic questions in this ecologically important family and order but also to address a number of challenges currently facing ascomycete systematics. These challenges include: 1) determining homology, character transformation series and patterns of variation for numerous morphological characters currently used in ascomycete taxonomy; 2) integrating teleomorph (sexual) and anamorph (asexual) taxa into a unified phylogeny and classification; 3) stabilizing generic, familial and ordinal concepts using a phylogenetic approach; 4) determining taxonomic diversity in tropical countries; 5) integrating all of these data into monographic treatments for diverse, ecologically and economically important taxa; and 6) producing students broadly trained in both traditional and modern aspects of collections-based research to swell the diminishing ranks of ascomycete systematists capable of undertaking monographic studies. This project directly addresses each of these challenges by:
1) Developing monographs for two species-rich, morphologically diverse genera in the Lasiosphaeriaceae, Chaetosphaeria Tul. and Tul. and Lasiosphaeria Ces and de Not. These are key to understanding phylogenetic relationships in the family, and are ecologically important as they appear to be dominant components of the neotropical litter decomposer mycota. Species circumscription will be based on morphological characters extracted from the whole organism including the teleomorph and anamorph states, and phylogenetic relationships will be assessed using both morphological characters and gene sequence data from nuclear rDNA. Field work will be undertaken in three sites in the USA and sites in Puerto Rico, Panama, and Ecuador. These sites were chosen based on the literature and on previous collection experience of the PI. Collections from these sites also will allow us to test several recent hypotheses on fungal biodiversity and biogeography. The monographs, along with the associated collections databases, data matrices, and illustrations of macro- and micromorphological features will be made available in both published form and over the Field Museum Mycology Gopher and Mosaic server.
2) Providing a phylogeny for these two genera and other genera in the large, diverse and important family Lasiosphaeriaceae and related families within the Sordariales. These phylogenies will be based on morphological characters and gene sequences from large and small subunit rDNA.
3) Providing an extensive student training program in modern collections-based research emphasizing both traditional aspects of monographic research and current systematic theory and methods. This program is developed to serve trainees at various levels of expertise to have the greatest impact on developing new taxonomic expertise in mycology. One postdoctoral associate, one graduate student, and several undergraduate interns will be trained.
The PI has extensive experience in monographic studies of ascomycetes and in tropical mycology (Huhndorf 1992a,b,c,d, 1993, 1994a,b). She has assembled a team of scientists to work with her on the project to ensure comprehensive expertise in all aspects of the research, training, computerization programs. This team includes the museum's two curators of mycology, Gregory Mueller and François Lutzoni, who will server as Senior Associates on the project. Additional resource personnel at the Field Museum include Drs. Qiuxin Wu (Collections Manager, Mycology), Jim Koeppl (manager of the computing department), John Hall (manager of the molecular systematics labs), Robin Foster (tropical plant ecologist), and several members of the zoology department including Drs. Barry Chernoff and Margaret Thayer. Other people committed to assisting with the program are faculty at collaborating universities including Prof. John Lussenhop (University of Illinois at Chicago), and international mycologists including Drs. Nils Lundqvist (Stockholm), John Krug (University of Toronto), and Françoise Candousseau (Pau, France).
The Lasiosphaeriaceae was chosen because 1) the group is diverse and unstudied; 2) the family contains ecologically and economically important genera and depending on the employed classification, either contains, or is the sister clade to, the family encompassing the model taxa Neurospora Shear and Dodge and Sordaria Ces and de Not.; 3) the group shows variation in morphological characters, some of which are crucial for understanding morphological evolution in the ascomycetes; 4) most of the species are relatively easy to culture, which allows for integration of anamorphs and teleomorphs and provides material to readily extract and amplify DNA; and 5) species in the family appear to be an abundant and commonly encountered part of the neotropical mycota based on preliminary fieldwork.


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The Sordariales (Fungi, Ascomycetes) contains 99 genera, divided among eight families. It includes many economically and ecologically important species including species of Ceratocystis and Chaetomium as well as the model taxa Neurospora crassa and Sordaria fimicola. However, recent phylogenetic analyses of DNA sequence data that included single representatives of four of the families of Sordariales suggest that the order is not monophyletic. A detailed assessment of the relationship among Sordarialean families is necessary to address this issue but before a meaningful sampling strategy can be devised, revisions of several key genera must be undertaken. The Lasiosphaeriaceae, 51 genera and about 1000 species, is the largest and most morphologically diverse family in the order, and in particular several of the species-rich genera in the family remain unstudied. Relationships among the genera are also unknown. In this study, we propose to prepare monographs of two of the largest genera in the Lasiosphaeriaceae, Chaetosphaeria and Lasiosphaeria, which have never been treated systematically and are key to understanding phylogenetic relationships in the family and the order. Species in the two genera are ecologically and economically important and although they have been described primarily from north temperate regions previous work by the PI suggests that they are a dominant part of the neotropical mycota involved with litter decomposition. Fieldwork will be undertaken in several sites in the U.S.A., Puerto Rico, Panama, and Ecuador to assess their ecological significance in more detail. These sites were chosen to sample areas with known high species diversity and to test several recent hypotheses on fungal biodiversity and biogeography. Based on the results of the monographic work, an assessment of phylogenetic relationships of Chaetosphaeria and Lasiosphaeria with the other genera currently included in the Lasiosphaeriaceae will be undertaken, this will facilitate critical analysis of relationships among the eight families of Sordariales. Both the monographic and the family level phylogenetic studies will be based on morphological and molecular data obtained from type and other herbarium specimens, newly collected specimens, and cultures. Results will be available via hard copy and over the Field Museum Mycology Gopher and Mosaic server. The program has been designed to provide comprehensive training in collections-based, monographic studies. This program directly addresses several of the major challenges currently facing ascomycete systematics including: a) rigorously examining patterns of variation in some of the key morphological characters currently used in ascomycete taxonomy, b) integrating sexual and asexual taxa into a unified phylogeny and classification, c) stabilizing generic, familial and ordinal concepts using a phylogenetic approach, d) determining taxonomic diversity in tropical countries, e) integrating these data into monographic treatments, and f) training students to become well versed in traditional as well as modern tools and analyses. Modern monographic treatments of ascomycetes are rare, and comprehensive treatments for species-rich genera currently are lacking. Thus, another important goal of this project is to publish monographs that will be used as models for future systematic work on ascomycetes.

Top of this Page | Title Page | Project and Background | Morphological Characters | Bibliography | Key to Genera |