Thelesperma simplicifolium, commonly known as the slender greenthread,[3] is a perennial, herbaceous, flowering plant in the Asteraceae family.

It is found from Texas and Mexico in openings in oak or juniper woodlands or on desert scrub.

[4] It typically grows in openings in oak or juniper woodlands or desert scrub (usually on limestone) at elevations of 100 to 1500 metres from sea level.

[4] As of December 2024[update], the conservation group NatureServe listed Thelesperma simplicifolium as Apparently Secure (G4) worldwide.

[5] As of July 2023, Plants of the World Online accepts two varieties of Thelesperma simplicifolium:[2]