Acanthocystis dentata  Leonov & Mylnikov, 2012

Diagnosis: Periplast is 30.0-37.0 μm in diameter, consists of plate-scales and spine-scales of two size classes. The short spine-scales are 3.0-4.0 μm, the long spine-scales are 10.0-15.0 μm, their shafts are straight. The apices of the spine-scales are ended with branched furcae carrying two teeth or one asymmetrical tooth. The plate-scales are elliptical or pear-shaped, 3.1-3.4 × 2.1–2.4 μm, ornamented with a small medial thickening, a thin rim and randomly located small granules.

Habitat: Freshwater. Karelia, Russia.