The record derives from TICA
(data supplied on )
which reports it as a synonym (record
21F65DA4-F6A8-4A42-AC0D-2659770939C1) with original publication details: "P.E. Boissier, Fl. Orient. 3. 1875" 745 1875.
This name record (from TICA) 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 Tragopogon longirostris in version 1 of The Plant List.