This name is a synonym of Pyracantha koidzumii (Hayata) Rehder.
The record derives from RJP
(data supplied on 2011-10-18)
which reports it as a synonym (record 7213) with original publication details: Formosan trees Formosan trees; 1918 213 1918.
This name record (from RJP) was not included in version 1 of The Plant List. It is possible the same name was included from a different data source, to check this you can search for Pyracantha formosana in version 1 of The Plant List.