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Genus Hamigera, six new species and multilocus DNA sequence based phylogeny.
Stephen W Peterson1, Zeljko Jurjevic, Gerald F Bills
1Microbial Genomics and Bioprocessing Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, U.S. Department of Agriculture, 1815 North University Street, Peoria, Illinois 61604, USA. stephen.peterson@ars.usda.gov
Mycologia
|July 23, 2010
Summary
Six new species of the fungal genus Hamigera were identified, expanding our understanding of fungal diversity. DNA analysis also led to the reclassification of Talaromyces striatus and clarified the placement of related fungal species.
Area of Science:
- Mycology
- Fungal Taxonomy
- Molecular Systematics
Background:
- The genus Hamigera was established for Talaromyces species characterized by solitary asci formation.
- Initially, the genus comprised two species: Hamigera avellanea and Hamigera striata.
Purpose of the Study:
- To describe six novel species within the genus Hamigera.
- To clarify the phylogenetic placement of Hamigera species and related fungi using molecular data.
- To re-evaluate the taxonomic status of Hamigera striata and other related species.
Main Methods:
- Phylogenetic analysis utilizing multiple DNA sequence markers including BT2, calmodulin, ITS, 1su rDNA, RPB2, Tsr1, and Mcm7.
- Morphological characterization of newly identified fungal species.
- Comparative analysis of DNA sequences for taxonomic classification.
Main Results:
- Six new species are described: Hamigera fusca, H. inflata, H. insecticola, H. pallida, H. paravellanea, and H. terricola.
- DNA sequence data indicated that Hamigera striata does not belong to the same clade as Hamigera avellanea, leading to its acceptance as Talaromyces striatus.
- Merimbla ingelheimensis was identified as a distinct anamorphic species within the Hamigera clade.
- Warcupiella spinulosa, Penicillium megasporum, Penicillium arenicola, and Merimbla humicoloides were phylogenetically analyzed, with M. humicoloides being placed in Penicillium to ensure the monophyly of the Hamigera genus.
Conclusions:
- The study expands the known diversity of the genus Hamigera with the addition of six new species.
- The reclassification of H. striata to Talaromyces striatus is supported by molecular evidence.
- The phylogenetic analyses provide a clearer understanding of the relationships within the Hamigera clade and related genera, ensuring the monophyly of Hamigera.
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