MicrobeHunter.com Microscopy Forum

Bruce Taylor wrote: ↑

Wed May 05, 2021 4:39 pm

Another beautifully clear video. You have an impressive ability to record ciliates!

This is certainly in Oxytrichidae, but I'm not convinced it is in genus Oxytricha. We see marginal cirri, joining posteriorly, two macronuclei, ventral cirri in a typical oxytrichid pattern. We don't see the full undulating membrane arrangement (just the bottom), and we don't see any sign of caudal cirri. Oxytricha species should have caudal cirri, though they can be inconspicuous and, in this case, might be below the focal plane. Overall, the cell looks a lot like Histriculus (=Histrio sensu Kahl), which usually has very well developed transverse cirri, arranged like these (thick, and sort of tapering to a point). However, Histriculus transverse cirri should not extend beyond the posterior of the cell, which these do (though very slightly). There are species of Sterkiella (e.g. Sterkiella histriomuscorum) which look similar, but these should have caudal cirri (though, as with Oxytricha, they might be inconspicuous or below the focal plane). I suspect this is Histriculus, but, given the uncertainty about the caudal cirri, Oxytricha and Sterkiella are also possible, so I wouldn't identify this guy below family.