This name is a synonym of Hieracium lachenalii subsp. cruentifolium (Dahlst. & Lübeck) Zahn.
The record derives from TICA
(data supplied on 2012-02-11)
which reports it as a synonym (record C1C008FA-4CBF-4039-A390-FFC21FDD7B9F).
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 Hieracium lachenalii in version 1 of The Plant List.