Maybe a Stitchotricha sp

[D0c]

Came across this in a soil sample the other day.

I think it's a stichotricha sp. I know they normally dwell in a lorica but there was no sign of this.

I struggled to get a good video of this critter, I think I had two much water beneath the cover slip on this occasion, a rookie mistake i know.

Another possibility i thought was Uroleptus but I wasn't convinced.

What are your thoughts.

https://www.flickr.com/photos/154534235 ... 007720092/
https://www.flickr.com/photos/154534235 ... 007720092/

[Bruce Taylor]

Stichotricha often leaves its lorica, so that is not a problem. However, I don't think this guy is in that genus, which normally features a necklike structure bearing the long, straight AZM, and also a somewhat rounded posterior. Here we have a distinctly cephalized cell (i.e. with a kind of "head"), with enlarged frontal cirri, a posterior that tapers into a sort of "tail," and (as near as I can tell at this magnification) ciliary rows (kineties) that spiral around the cell. It is probably a species of Strongylidium, such as S. lanceolatum. Uroleptus can have a similar body shape, but typically with much smaller frontal cirri, and a larger concave-looking buccal area between the paroral membranes and the AZM. Also, the ventral surface would have a double file of cirri (zigzag midventral complex) which runs straight down the middle of the cell without spiraling around it.

[D0c]

A massive thanks Bruce.

Can't seem to find much about this critter on google, why is this, is it pretty rare or just under documented.

[Bruce Taylor]

I don't think members of the genus are particularly rare (though there are certainly rare and/or under-reported species). For instance, a quick search in Google Scholar shows that S. lanceolatum turns up fairly often in ecological surveys. The genus was revised in 2007 by Paiva and Silva-Neto, along with a redescription of S. pseudocrassum: https://www.researchgate.net/publicatio ... chotrichia