Litonotus duplostriatus

[janvangastel]

My North Sea sample is full of Pleurostomatidae at the moment. When I started observing this sample I only found very few, but now, after about ten days, its the most abundant ciliate of which I see at least 15 in every slide I observe. two days ago I found this nice one. I think it is Litonotus pleurostratus, because of its nice 'double rib' feature, most clearly visible at the beginning of this video. I found the name in Kahl (vol. 2, page 192).

[Bruce Taylor]

A really nice video! Your species-level ID is very plausible. However, marine ciliates have been poorly studied until recently, so you will not get a good sense of the real diversity from Kahl. In a recent redescription of Litonotus duplostriatus, the authors list 6 species with a similar morphology that should be compared. Of those, 4 were unknown to Kahl! The one they describe as "most similar", L. songi, is differentiated on the basis of fairly inconspicuous features, such as the shape of the individual extrusomes: https://www.sciencedirect.com/science/a ... gMMkOkuElA

[janvangastel]

Thanks Bruce. There are always more possibilities then I am aware of when ID-ing. Makes it difficult, but also interesting.

[Bruce Taylor]

Yes! And there are more possibilities than anyone is aware of, because so much ciliate diversity remains undescribed.

[Rapidray]

Great video and excellent double rib movement!