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Taxonomy Phylogeny
    |  `--Trichomycetes
       |  |--Ustilaginomycetes
       |  `--Hymenomycetes
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Bread mould
Zygomycotes, like chytrids, are known from the Rhynie Chert, although, in this case, the identification is more tentative. What are actually seen are fungal hyphae which appear to pierce other cells, a characteristic of many zygomycotes. Definitive zygomycotes are found in Carboniferous exposures. A more familiar present-day example of a zygomycote is Rhizopus, the black bread mold.

The Zygomycota are named for their characteristic teleomorph, which is referred to as a zygosporangium. The images at the glossary entry for gametangium are of Phycomyces and Rhizopus, both zygomycotes. They illustrate how the zygosporangium is formed from the head-on meeting of two hyphae whose ends have specialized as gametangia. The contents of the gametangia are mixed in the zygosporangium, which develops between them. The haploid nuclei from the gametangia then fuse. The zygosporangium develops a hard, thick chitin shell, which is frequently ornamented and may bear spines or other appendages. The remains of the gametangia protrude from the sides and are referred to as suspensors. The zygosporangium also serves as a resting phase, which will develop when conditions are favorable.

Zygomycotes also reproduce asexually. The haploid spores develop in a bulbous mitosporangium at the tips of specialized vertical hyphae referred to as sporangiophores.

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