Isoetes valida

Isoetes valida, commonly known as the strong quillwort or true quillwort, is an aquatic lycophyte native to eastern North America. It is found primarily in the Appalachian Mountains from Pennsylvania south to Alabama and Georgia. In addition, one collection of the plant was made in a railway ditch in Wilmington, Delaware in the 1860s, but this was most likely an accidental introduction.^[3][4]

Isoetes valida
Conservation status
Apparently Secure  (NatureServe)[1]
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Lycophytes
Class:	Lycopodiopsida
Order:	Isoetales
Family:	Isoetaceae
Genus:	Isoetes
Species:	I. valida
Binomial name
Isoetes valida (Engelm.) Clute
Synonyms[2]
I. engelmannii var. valida

Some sources consider Isoetes caroliniana a synonym of this species,^[5] others regard it as a separate species.^[6]