Paraphyses

Paraphyses are filament-like support structures in the reproductive apparatuses of fungi, ferns, and moses.

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.