Frontonia accuminata?

[janvangastel]

I think this is Frontonia accuminata because of the black 'spot' at the rear end. I have found one before, but its black spot was smaller. And the trichosysts are not present or less clear. So it could easily be another ciliate.

[Bruce Taylor]

Frontonia acuminata typically has a concentration of pigment (black spot) in the anterior of the cell, rather than the posterior, but this could just be an anomalous individual. We don't see the mouth very clearly, but it does look like Frontonia...flattened cell, slightly acute at the posterior, trichocysts, oval mac, single CV (a bit more posterior than usual).

[janvangastel]

Thank you Bruce.