Help with ID, please

[scotspencer]

I'm new to microscopy and I've come across some organisms that I'm not sure how to identify. The close-up picture was taken with a 40x objective and the other was with a 10x. Are they Vorticella?

[Olympusman]

Yes, they are vorticella.

[rjlittlefield]

scotspencer, welcome aboard!

Since you're new to microscopy, I'll mention that the microscopic world is small in size but huge in variety. In casual usage, the word "vorticella" is sometimes used as a collective term to describe any protists that have this general appearance with a vase-shaped body and a stalk that fastens them to a substrate. But within that group there are finer distinctions based on form and habits, and from the standpoint of scientific naming Vorticella is only one genus among many. Quoting from T.L.Jahn, "How To Know The Protozoa",

Vorticella is often found in clusters, but these clusters are not colonies, i.e., the stalk of each organism is attached directly to the substrate. In other genera described below the stalk is branched, and may be non-contractile (Epistylis, Opercularia) or contractile only as a single unit, i.e., the whole colony contracts at the same time Zoothamnium), or each branch contractile as an independent unit (Carchesium).

From the images here, I can't tell for sure what branching structure your organisms have. I get the feeling that there is some sharing of the stalks, which would argue against Vorticella as a particular genus. But certainly you have something in this general group.

--Rik

[scotspencer]

Thanks RJK,

That's very interesting and helpful information. From what you posted it sounds like they may be Epistylis or Opercularia. I've observed them quite a bit (I have a plentiful supply in my aquarium) and haven't ever observed any contracting. Also, their stalks do branch.

Scot
Kentucky, US

[Bruce Taylor]

(Oops...tried to edit, and deleted instead )

To repeat...it is an epistylid, and probably Campanella (a closer view of the oral structures would confirm the genus). The stalks have no myoneme (long central fibre, permitting the stalk to contract), which rules out any of the Vorticellidae or Zoothamnidae.