MicrobeHunter.com Microscopy Forum

Not sure if there are any saltwater experts here. My saltwater sample which was empty a week ago is now bursting with ciliates. This video shows 2 of the most prolific. First, a slender ciliate about 60-70 microns long with a very cool cilia structure. Second, a 60 micron ciliate that behaves somewhat like euplotes in that it can use its cilia to "walk" along strands of algae. Thanks for any IDs.

The slender ciliate is a species of Cohnilembus. The walking ciliates are Euplotes.

Bruce Taylor wrote: ↑

Thu Dec 15, 2022 7:39 am

The slender ciliate is a species of Cohnilembus. The walking ciliates are Euplotes.

Thanks Bruce. So Euplotes is found in both fresh and salt water? Wouldn't their biology need to be different to survive in both environments?

macnmotion wrote: ↑

Thu Dec 15, 2022 8:01 am

Thanks Bruce. So Euplotes is found in both fresh and salt water? Wouldn't their biology need to be different to survive in both environments?

Yup. Some species of Euplotes are found only in salt and brackish water, some are found only in freshwater. Some morphospecies have been reported in both. Either these latter species are just versatile and adaptable, or there is some cryptic diversity separating their marine and freshwater populations (differences that don't appear in morphology).

It's not unusual for a genus to include both marine and freshwater species. For instance, Holosticha is primarily a marine genus, but it has one species (H. pullaster) which is extremely common in ponds and ditches. And some genera, like Cohnilembus, are confined to marine waters, with no known freshwater species.

Bruce Taylor wrote: ↑

Fri Dec 16, 2022 1:17 am

macnmotion wrote: ↑

Thu Dec 15, 2022 8:01 am

Thanks Bruce. So Euplotes is found in both fresh and salt water? Wouldn't their biology need to be different to survive in both environments?

Yup.

Thanks. I'm fortunate to live in a location with fresh, marine and brackish water sources (it's just a matter of getting to each). I'll keep my eyes out for consistencies between the three.