Phylum: Charophyta   Family: Desmidiaceae

Cosmarium luxuriosum var. papilliforme  D.B. Williamson & C. Johnson

The habitat is the same as for the nominate variety. The original find and subsequent finds have all come from the same geographical area and within a few hundred metres of each other. The 'By Loch Druim na h-Imrich' sample had several cells of the nominate variety but only a single cell with the papillae was found.

References: 
Williamson, D.B. & Johnson, C. (2021) Cosmarium luxuriosum var. papilliformis var. nov.: A new desmid variety from the Outer Hebrides