Among Lycophyta families, the Isoetaceae are easily recognized by their herbaceous habit resembling grasses, and by their aquatic or paludicolous life form. This family is recognized in Peru with one genus, Isoetes, and 10 species (Hickey, 1994; Smith et al., 2005). The species, with the exception of two, are represented in the High Andean region, associated with lakes and wetlands. Four species are considered to be endemics, two are submerged aquatics and one is facultative. One endemic species is found within a protected area, although threat to its populations are of concern (León & Young, 1996).