Iostephane is a genus of Mexican flowering plants in the family Asteraceae. They were first published in G.Bentham & J.D.Hooker, Genera Plantarum Vol.2 on page 368 in 1873.
The species are rosette-forming herbaceous perennials that produce relatively large heads with yellow or purple (I. heterophylla) rays. They have large, somewhat quadrate cypselae (achenes), that may either have or lack a pappus.
Molecular phylogenetic studies by Schilling in 1991, suggested that there is an unexpectedly close relationship between Iostephane and Dendroviguiera (formerly Viguiera sect. Maculatae), a genus of shrubs and trees that is also endemic to Mexico.
As accepted by Plants of the World Online, and Global Compositae Checklist;