Syzygites
From Wikipedia, the free encyclopedia
| Syzygites | |
|---|---|
 | |
| Hyphae of Syzygites megalocarpus growing on a bolete. | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Fungi |
| Division: | Mucoromycota |
| Class: | Mucoromycetes |
| Order: | Mucorales |
| Family: | Mucoraceae |
| Genus: | Syzygites Ehrenb. |
| Species: | S. megalocarpus |
| Binomial name | |
| Syzygites megalocarpus | |
| Synonyms[1] | |
| |
Syzygites is a monotypic genus in Zygomycota. The sole described species is Syzygites megalocarpus, which was the first fungus for which sex was reported and the main homothallic representative in the research that allowed for the classification of fungi as homothallic or heterothallic. It is also the fungus from which the term "zygospore" was coined.[2]
Syzygites megalocarpus produces phototropic, repeatedly dichotomously branched sporangiophores that terminate in globose, apophysate sporangia.[3] Sporangiospores have a spinose wall, which is rare in Mucorales.[4] Zygospores are pigmented, ornamented, and produced on equally sized suspensors. Due to the presence of carotenoids, the myceliuem can appear yellowish, though mature sporangia darken giving it a brownish appearance.[1][5][6]
Ecology
S. megalocarpus is a necrotrophic parasite of mushrooms in temperate regions,[4] though there are reports of it from ascomycetes.[1] It can parasitize at least 98 different species and is itself parasitized by Piptocephalis virginiana. Syzygites megalocarpus is likely a faculative parasite as it can be grown on a variety of media, including bread, in the laboratory. Development of asexual sporangia and zygospores are highly dependent upon environmental conditions. In the laboratory, growth occurs between 5-30 degrees Celsius. Alternating light and dark increases the formation of sporangiophores and continual darkness increases the production of zygospores. Lower temperatures favor zygospore formation and higher temperatures favor sporangiophore production. Media with high quality carbon sources favors formation of zygospores, while media with high nitrogen favors formation of sporangiophores. High humidity increases zygospore formation and low humidity increases sporangiophore formation.[5]