Psilotaceae

plant family

Also known as: whisk fern family

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Last updated

July 13, 2026

Quick Summary

Psilotaceae is a family of plants typically placed in the order Psilotales. These plants are characterized by stems that are nearly naked, with very small, scalelike leaves. They also possess sporangia (structures that produce spores) that are either two- or three-celled.1

The order Psilotales includes lower tracheophytes, which are vascular plants. These plants have a sporophyte (the spore-producing generation) that is divided into an aerial shoot and a rhizome (underground stem). Notably, they lack true roots and have few or minute leaves. Their gametophyte (the gamete-producing generation) is subterranean and does not contain chlorophyll. The family Psilotaceae includes genera such as Psilotum and Tmesipteris.21

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fern
Annotated classification
ferns) Family Psilotaceae Plants lacking true roots, stems dichotomously branched, protostelic (the stele lacking pith and leaf gaps); leaves reduced to minute scalelike outgrowths (enations) without veins, or small, flattened, and undivided, with a single midvein (microphylls), not developing through circinate vernation; sporangia eusporangiate in fused clusters…
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ferns) Family Psilotaceae Plants lacking true roots, stems dichotomously branched, protostelic (the stele lacking pith and leaf gaps); leaves reduced to minute scalelike outgrowths (enations) without veins, or small, flattened, and undivided, with a single midvein (microphylls), not developing through circinate vernation; sporangia eusporangiate in fused clusters…
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