Paraphyses

Paraphyses are erect sterile filament-like support structures occurring among the reproductive apparatuses of fungi, ferns, bryophytes and some thallophytes.

In certain fungi, they are part of the fertile spore-bearing layer. More specifically, paraphyses are sterile filamentous hyphal end cells composing part of the hymenium of Ascomycota and Basidiomycota interspersed among either the asci or basidia respectively, and not sufficiently differentiated into specialized, swollen, often protruding cells to be called cystidia.

In ferns and mosses, they are the filament-like structures that are found on sporangia. They are found between clusters of archegonia and antheridia.

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