Psilotum (whisk fern)'s a genus of fern-like vascular plants, one of two genera in the family Psilotaceae, order Psilotales, and class Psilotopsida (the other being Tmesipteris). Species and distribution There're two species, Psilotum nudum and Psilotum complanatum, with a hybrid between them known, Psilotum × intermedium W. H. Wagner. The distribution of Psilotum's tropical and subtropical, in the New World, Asia, and the Pacific. The highest latitudes known are in South Carolina and sout… (More on Psilotum)