This name is a synonym of Sedum laxum (Britton) A. Berger.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 8901433) with original publication details: Bull. Torrey Bot. Club 69(1): 36–37 1942.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:231765-2.
This name was in version 1 of The Plant List, record tro-8901433.