This ranges widely over western and northeastern North America, but towards it is generally restricted to moist acid soils in shady ravines. The disjunct record from JEFF is based on a coll. with somewhat dubious incomplete data, from "Mud Creek Swamp" ca. 1950s (DHL). The genus Huperzia differs from Lycopodiaceae sensu stricto as follows (FNA 2, W): spores pitted to small-grooved (versus reticulate or rugulate); sporophylls similar to sterile leaves or only slightly reduced, in annual bands along the stem (versus distinctly broader and shorter or more spreading, in terminal cones); leafy stems clustered (versus spaced along rhizone), erect or pendant, simple or dichotomously branched (versus prostrate or erect, if erect then generally branched); ultimate branches vertically oriented upwards or downwards (versus spreading or ascending); vegetative reproduction by leafy gemmae near the stem apex (versus not so).