⚠ Version 1 of The Plant List has been superseded.

This name is in version 1.1 of The Plant List, record tro-1600484, with some changes.

Unonopsis williamsii R.E. Fr. is a synonym of Unonopsis guatterioides (A.DC.) R.E.Fr.

This name is a synonym of Unonopsis guatterioides (A.DC.) R.E.Fr..

The record derives from Tropicos which reports it as a synonym (record 1600484) with original publication details: Acta Horti Berg. 12: 238, f. 6 f, t. 1 238 1937.

Full publication details for this name can be found in IPNI: urn:lsid:ipni.org:names:259535-2.