Phylum: Charophyta   Family: Desmidiaceae

Micrasterias conferta P.M. Lundell 1871

West & West (1905: 88) comment that it's one of the rarest British species, found largely in the north-west of Scotland, also western Ireland. One of the main distinguishing features is the broad polar lobe.
Single cell dimensions: L: 92 µm; B: 88 µm; Is: 16.9 µm; L/B: 1.05.
An acidophile found in moorland peaty pools.

References: 
Coesel, P.F.M. & Meesters, K.J. (2023 second edition). Desmids of the Lowlands.
West, W. & West, G.S. (1905). A Monograph of the British Desmidiaceae, Volume 2.