Spheres in Spheres

[Heliozian]

Hi There

I have been enjoying identifying a fair few things (at least to a group or a genus) but there are plenty of things which still leave me baffled.
In water from our little pond which has been sitting near a window for a month with a couple of crushed wheat grains to busy things up a bit I have found these spheres in spheres. The larger spheres are about 70 - 100µ in diameter, the small ones about 18 - 20µ. So far I've not seen them do anything - the only activity is that bacteria seem to like them and are wiggling about on the surfaces of the larger spheres. The large spheres seem to have an opening and the smaller ones seem to fall out as and when they are disturbed. There are a lot of them around - some parts of the slide really are littered with them.

Does anyone have any idea what I'm looking at? I wondered about Copepod eggs but the egg sacks on Copepods don't seem to be so spherical and the Cyclops in this sample have egg sacks which are 300 - 500µ long or so - much larger than these.

I've added three pics, I'm fairly sure they are fungal spores within asci - any thoughts on what genus or species?

Many thanks

Ian

[Plasmid]

Ian your assumption is correct,those appear to be indeed fungal spores, the large sack is called the ascus and the spheres inside it are ascospores. Google Ascomycota and it should get you closer to finding a genus and or species.
Picture number one shows a septate hyphae thay should help you narrow it down.
From wikipedia
" A cleistothecium is a globose, completely closed fruit body with no special opening to the outside. The ascomatal wall is called peridium and typically consists of densely interwoven hyphae or pseudoparenchyma cells. "
Good luck

[Rylander]

Hi Heliozian, it is not an ascomycet as you have found but it is a genus of water mold, Saprolegnia which belongs to the group Oomycetes.
See pictures at this link

http://protist.i.hosei.ac.jp/PDB/Images ... index.html

Sincerely, Rylander

[Heliozian]

Many thanks both for your help

I did post the question on the British and Irish Fungi Facebook group and had a reply a day or two ago from a chap called Brian saying "look up Saprolegnia and Oomycetes" with a link to https://plantlet.org/oomycetes-order-saprolegnia/ which proved to be helpful. They do look a lot like fungal spores but after quite a bit of searching I couldn't find anything which quite fit the bill amongst the fungi. The Saprolegnia, on the other hand, fit the bill perfectly. It's also been an interesting learning experience discovering that long held beliefs regarding potato blight and mildew being fungi were wrong! They are both Oomycetes.

I hope to have the chance to take another look at them on Saturday to see if I can see the zoospores as well as the oospores. Apart from anything the names are just fab - the oospores in the oogonium - great language!
I particularly like them as I've been interested in slime moulds for a little while and the Myxomycetes and Oomycetes seem to be rather parallel groups of non-fungal members of the protoctista. There's so much to learn!

The world of the small is fascinating, and that fascination is only increased by its reluctance to fit in with the simple animal, plant, fungi categories of most of the macro world. The confusing mess of relationships within the rag bag category of "protoctista" reminds us that the world is more complicated than we are generally comfortable with which I rather like!

Thanks again and all the best,

Ian

[DonSchaeffer]

Interesting. I find these a lot and wondered what they are.

[HowardHopkinson]

What a fantastic and educational thread. Super interesting too!

[Heliozian]

I'm glad you enjoyed it Howard - there is always so much new stuff to learn - I find it both exciting and somewhat daunting