MicrobeHunter.com Microscopy Forum

Hi folks,
This critter came out of the debris from the bottom of a water trough.
It appeared to graze on the pieces of algae as it swam around.
It was possibly 5mm long.
Head is to the right.
Thanks
Grahame

Guessing ... Worm, possibly Aquatic Oligochaeta

see link: Tools for identifying Australian aquatic oligochaetes of the families
Phreodrilidae, Lumbriculidae and Capilloventridae (Clitellata: Annelida)

https://museumsvictoria.com.au/media/38 ... ne2013.pdf

Thanks 75RR,
Interesting pdf.
It may have given me the id of another thing I've seen a couple of times, looks like they could be worm egg sacs.

I believe that's Chaetogaster Diaphanus. I successfully cultured these for a short time several years ago.

Edit, C. Diaphanus is an active carnivore, its preferred prey is tiny micro-crustacea. If your specimen was feeding on algae, it might be some other species of genus Chaetogaster.

Hi Rick,
Thanks for the id.
I checked the New Zealand Organisms Register, our list of everything known to live in NZ and Chaetogaster diaphanus does live down here.
The only other is Chaetogaster diastrophus.
There were all sorts of small critters and a few rotifers in that water sample so it's quite possible that what I though was a quick graze on algae was actually grabbing something from under the piece of algae.
I've added an image of what I now think is a worm egg sac.
Any chance this may belong to C. Diaphanus ?
Thanks again
Grahame

According to Ward & Whipple, and Pennak, Chaetogaster spends much of its time reproducing asexually by growing another zooid behind the active one, and then budding it off. They also lay eggs, but I have no idea what they would look like, and don't recall seeing descriptions of them.

Thanks Rick,
The many and varied forms of reproduction never ceases to amaze me.