This name is a synonym of Sphaeralcea munroana var. subrhomboidea (Rydb.) Kearney.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50298701) with original publication details: Bot. Mag. 65: pl. 3698 1838.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:561606-1.
This name was in version 1 of The Plant List, record tro-50298701, and has not been changed.