Is this Dileptus?

[MikeBradley]

I’m trying to ID this protist, wondering whether it is Dileptus? It was from a freshwater pond plant bed, in the company of a healthy population of closterium and cosmarium. It was imaged at 40X 0.95NA and in the shape captured in the image it was 150um in length. Thanks for any help
Michael.

[Javier]

It does not look like Dileptus to me. Have you checked Stichotrica?

[Bruce Taylor]

It is definitely not Dileptus, or any dileptid. It has adoral membranelles, which that group does not possess. It appears to be a heterotrich, but could also be a hypotrich. Do you have other images, or video? What size was it?

[MikeBradley]

Thanks for the correction Bruce, I've a lot to learn! Unfortunately my only other serviceable image of this specimen doesn't offer me much more of assistance in ID'ing it. In my original posting I said the image was at 40x, but it was actually only 20x, as a result the specimen was actually 300um at the time the image was taken, when fully extended it was well over 400. This second image was definitely taken at 40x!
Thanks.
Michael

[Bruce Taylor]

Ah, so it's big. I think it's a rather ragged Blepharisma.

[MikeBradley]

Thanks Bruce, I had started to wonder whether that may have been the answer.
Thanks
Michael

[Bruce Taylor]

It's a bit pink, here and there.