This name is a synonym of Avena murphyi Ladiz..
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 469097) with original publication details: Genet. Resources Crop Evol. 45: 263 1998.
This name record (from WCSP) 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 Avena insularis in version 1 of The Plant List.