Retimohnia glypta is a species of saprobic and potentially weakly pathogenic fungus belonging to the family Mohniaceae within the phylum Ascomycota. It is primarily known for its association with coniferous trees, particularly pines, in North America, where it can contribute to sapwood staining and canker formation.
Taxonomy
- Kingdom: Fungi
- Phylum: Ascomycota
- Class: Sordariomycetes
- Order: Xylariales
- Family: Mohniaceae
- Genus: Retimohnia
- Species: Retimohnia glypta
The species was originally described as Mohnia glypta by mycologist A. Funk in 1982. It was subsequently reclassified into the newly established genus Retimohnia by J.R. Stone and M.E. Barr in 2007. This reclassification was based on distinctive morphological characteristics, particularly concerning the structure of its ascomata (fruiting bodies) and the ornamentation of its ascospores.
Description and Characteristics
Retimohnia glypta produces distinctive fruiting bodies (ascomata) that are typically embedded within the host substrate, often appearing as small, dark structures on the surface of wood or bark. Microscopically, the fungus is characterized by:
- Ascospores: These sexual spores are typically brown, ellipsoidal, and exhibit a unique, sculptured or reticulate (net-like) surface pattern. This intricate surface ornamentation is reflected in the specific epithet "glypta," derived from the Greek word "glyptos," meaning carved or sculptured.
- Conidia: The fungus also produces asexual spores (conidia), which play a role in its asexual reproduction and dispersal.
The establishment of the genus Retimohnia was prompted by specific features of its ascomata, which are typically carbonaceous, subglobose to pyriform (pear-shaped), and can be immersed in or superficial on the substrate, alongside its distinctive spore morphology.
Ecology and Habitat
Retimohnia glypta is primarily a saprobic fungus, meaning it obtains nutrients from dead organic matter. It is frequently isolated from the wood and bark of coniferous trees, especially ponderosa pine (Pinus ponderosa) and lodgepole pine (Pinus contorta) in western North America. While generally considered saprobic, it has also been associated with sapwood staining and canker formation on living trees. This suggests it can act as a weak pathogen, particularly on stressed or wounded hosts. Its presence can lead to discoloration of the wood, potentially impacting timber quality.
Distribution
The species is predominantly found in North America, with records spanning various coniferous forest regions, particularly in the western United States and Canada.
References
- Funk, A. (1982). Mohnia glypta sp. nov. from western conifers. Mycotaxon 15: 476-480.
- Stone, J.R. & Barr, M.E. (2007). Retimohnia, a new genus of Xylariaceous fungi, with Retimohnia glypta comb. nov. and Retimohnia pinastri sp. nov. Sydowia 59(2): 203-214.