- Isoetales, order Isoetales - aquatic or marsh-growing fern allies; known to have existed since the Cenozoic; sometimes included in Lycopodiales
--1 is a kind of plant order
--1 is a member of Lycopsida, class Lycopsida, Lycopodiate, class Lycopodiate
--1 has members: Isoetaceae, family Isoetaceae, quillwort family