Colors

Data mode

Account

Login
Sign up

Collapse this

Support the Flora of the Southeastern US

2024 has been a banner year for making the best flora we can imagine. We've created:
With financial support from people like you, we are aiming even higher in 2025. Together we can accomplish all this: Vote on our 2025 priorities
  • Add Global Conservation Ranks (GRanks) vote
  • Professional graphic keys (polyclaves) to individual families/genera vote
  • 2 new FloraQuest apps: Florida & Mid-South vote
  • Image overlays highlighting diagnostic characters with arrows vote
  • iNaturalist integration in FloraQuest vote
Write-in vote: vote
We've set a goal of recruiting 200 ongoing supporters to donate $15 or more each month in 2025. Please help us reach this goal and make next year's flora even better:
Copy permalink to share

Psilotum Swartz. Whiskfern.

A genus of 2 species, tropical and warm temperate. Psilotum lacks roots and true leaves. Other than the Australasian genus Tmesipteris, Psilotum has no close living relatives, and the 2 genera have sometimes been considered to comprise a distinct class (Wagner 1977), though PPG I (2016) treats the family in Order Psilotales in Subclass Ophioglossidae. The stem is chlorophyllous. Fungal cells interspersed in the outer layers of the rhizome aid in the absorption of nutrients.

ID notes: The stiff, dichotomously-branched habit of Psilotum is unmistakable.

Ref: Kramer & Green (1990); Lellinger (1985); PPG I (2016); Thieret (1993) In Flora of North America Editorial Committee (1993b); Wagner (1977); Zhang & Yatskievych in FoC (2013). Show full citations.

Show in key(s)

Show parent family

Show species in Psilotum

Your browser does not support SVGs

Hover over a shape, letter, icon, or arrow on the map for definition or see the legend. Data for arrows not developed for genera and families which may have species only occurring outside the flora area.

image of plant© Alan Cressler: Psilotum nudum, Atlanta Botanical Garden, Altanta, Fulton County, Georgia 2 by Alan Cressler | Psilotum nudum source | Original Image ⭷
image of plant© Alan Cressler: Psilotum nudum, Atlantic Coastal Ridge, Hypoluxo Scrub Natural Area, Palm Beach County, Florida 1 by Alan Cressler | Psilotum nudum source | Original Image ⭷

Feedback

See something wrong or missing on about Psilotum? Let us know here: (Please include your name and email if at all complicated so we can clarify if needed.) We greatly appreciate feedback, and will include updates from you in our next webapp update, which can take a few months.