This name is a synonym of Deutzia parviflora var. micrantha (Engl.) Rehder.
The record derives from WCSP (in review)
(data supplied on 2012-03-23)
which reports it as a synonym with original publication details: Bot. Jahrb. Syst. 36(82): 51 1905.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:790870-1.
This name was in version 1 of The Plant List, record kew-2763292, and has not been changed.