Persistent hamathecial threads in the Nectriaceae, Hypocreales: Thyronectria revisited and re-instated
1Division of Systematic and Evolutionary Botany, Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, A-1030 Vienna, Austria;
Persoonia
|March 5, 2015
Summary
The fungal genus Thyronectria is reinstated within the Nectriaceae family, incorporating species previously assigned to Pleonectria and Mattirolia. This taxonomic revision is supported by molecular phylogenies and re-examination of fungal morphology.
Area of Science:
- Mycology
- Fungal Taxonomy
- Molecular Phylogenetics
Background:
- Species previously classified under Pleonectria and Mattirolia were often misassigned due to the presence of paraphyses, leading to their inclusion in Thyridiaceae.
- Molecular phylogenetic analyses have revealed a distinct lineage within Nectriaceae characterized by specific ascomatal features.
- The genus Thyronectria, originally described, requires re-evaluation based on new data and taxonomic criteria.
Purpose of the Study:
- To reinstate the genus Thyronectria based on type studies and new collections.
- To clarify the taxonomic placement of species formerly in Pleonectria and Mattirolia.
- To provide a comprehensive revision of Thyronectria, including new species and a diagnostic key.
Main Methods:
- Molecular phylogenetic analyses utilizing multiple genetic markers (act, ITS, LSU rDNA, rpb1, rpb2, tef1, tub).
- Re-examination of type specimens and freshly collected fungal material for morphological characterization.
- Phylogenetic analysis including the type species of Thyridium to establish inter-familial phylogenetic distances.
Main Results:
- The genus Thyronectria is re-instated in the Nectriaceae, encompassing species with persistent apical paraphyses and diverse ascospore morphologies.
- Mattirolia and Thyronectroidea are confirmed as synonyms of Thyronectria.
- Three new species, T. asturiensis, T. caudata, and T. obscura, are described and added to the genus Thyronectria.
Conclusions:
- Thyronectria represents a distinct genus within Nectriaceae, characterized by persistent apical paraphyses, irrespective of ascospore pigmentation or septation.
- The revision consolidates species from related genera into Thyronectria, improving taxonomic clarity.
- This study provides a robust phylogenetic framework and taxonomic key for the genus Thyronectria.
Related Concept Videos
01:23Phylogeny
64.8K
Phylogeny is concerned with the evolutionary diversification of organisms or groups of organisms. A group of organisms with a name is called a taxon (singular). Taxa (plural) can span different levels of the evolutionary hierarchy. For instance, the group containing all birds is a taxon (comprising the class Aves), and the group of all species of daisies (the genus Bellis) is a taxon. Phylogenies can likewise include just one genus (i.e., depict species relationships) or span an entire kingdom.
64.8K
03:21Phylogenetic Trees
52.3K
Phylogenetic trees come in many forms. It matters in which sequence the organisms are arranged from the bottom to the top of the tree, but the branches can rotate at their nodes without altering the information. The lines connecting individual nodes can be straight, angled, or even curved.
52.3K
03:21Phylogenetic Trees
6.8K
6.8K
02:40Epiphytes, Parasites, and Carnivores
17.2K
Plants often form mutualistic relationships with soil-dwelling fungi or bacteria to enhance their roots’ nutrient uptake ability. Root-colonizing fungi (e.g., mycorrhizae) increase a plant’s root surface area, which promotes nutrient absorption. While root-colonizing, nitrogen-fixing bacteria (e.g., rhizobia) convert atmospheric nitrogen (N2) into ammonia (NH3), making nitrogen available to plants for various biological functions. For example, nitrogen is essential for the...
17.2K
02:26Non-vascular Seedless Plants
76.1K
The diverse plant life on Earth—consisting of nearly 400,000 species—can be divided into three broad categories based on biological characteristics: nonvascular, seedless vascular, and seed plants.
76.1K
01:21Hyperthermophilic Bacteria
774
Domain Bacteria includes some unique hyperthermophilic species. They exhibit remarkable adaptations that enable survival in extreme environments.Thermotoga species are rod-shaped, gram-negative, non-sporulating hyperthermophiles that form a sheath-like envelope called a toga. They ferment sugars or starch, producing lactate, acetate, CO₂, and H₂, and can also grow via anaerobic respiration using H₂ and ferric iron. Found in hot springs and hydrothermal vents, over 20% of their...
774