The taxonomy of Cruoriopsis and some other genera now in the family Peyssonneliales, including Cruoriella and Cruoria, have been the subject of much discussion over decades.[1][2][3][4] Cruoriopsis first became synonymous with Cruoriella,[1] which in turn became synonymous with Peyssonnelia.[5] Despite the fact that Cruoriopsis is an unaccepted name taxonomically, four species remain within Cruoriopsis incertae sedis: C. danica, C. ensisae, C. hauckii, and C. reinboldii.[6][7]
The holotype species of this genus was originally described and named Cruoriopsis crucialis in 1865.[8] However, this is no longer the accepted name and it was reclassified as Peyssonnelia armorica in 1916.[9] Another species in a different genus, Cruoriella armorica, that was described in 1869 is now also considered synonymous with P. armorica.[10]
