Phylum: Charophyta Family: Desmidiaceae
Euastrum brevisinuosum (O. Nordstedt) F.A.C. Kouwets 1984
Emendation of Nordstedt’s (1888: 57, pl. 6: 9) original description – from Kouwets (1984: 338).
“Small Euastrum species, length/breadth ratio 1-2-1-5, semicells trapezoid in outline with concave sides; apex retuse-emarginate in the middle; sinus shallow and dilated towards the end. Apex in end view oblong-rectangular with rounded angles and emarginate sides; basal lobes in apical view rounded. Side view of the semicell quadrate-pyramidate; apex often slightly emarginate. Both in end and in side view a large basal inflation is visible on either side of the semicell. Cell wall sculptured with coarse dots which may be more prominent on the angles of the semicell and on its basal inflations."
Cell dimensions: L: 21-35 µm; B: 14-23 µm; Is: 8-16 µm; Th: 12-17 µm; L/B: 1.30-1.40.
A species of Arctic-alpine regions, occurring in acidic mesotrophic bogs and lochans, also on wet rocks. Rarely encountered.
References:
Kouwets, F.A.C. (1984) The Taxonomy, Morphology and Ecology of Some Smaller Euastrum Species (Conjugatophyceae, Desmidiaceae).
Nordstedt, O. (1888) Fresh-water algae, collected by Dr S. Berggren in New Zealand and Australia.