? freshwater fungi

[sreynolds]

I find this on rocks and pebbles near shore in a Vermont stream, where I would expect to find diatom growth and/or filamentous algae. Is it a fungus? Filament structure is hard for me to image because the filaments are transparent and very thin even at 40x objective. Growth on rocks is very thin, i.e. scraping with a scalpel yields very small amount of material.

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The cells with chlorophyll mostly look like this - maybe it's not chlorophyll? Color rendering is natural. Thanks.

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[apochronaut]

I suspect you are seeing a couple of different species. The strands radiating ftom the clump in picture 2 might not be the same as those in the more open areas. Do any of them move at all?
Some look like gliding bacteria , thioploca or maybe beggiatoa.

[sreynolds]

[Edit of original reply]
I will get another sample and try for better pictures. From what I've seen so far, nothing moves quickly, although I haven't looked for slow movement.

[sreynolds]

I suspect you are seeing a couple of different species.

I may be making progress on the 'strands radiating from clumps'. They appear to originate in one of the round green cells shown in the picture above; I found one by itself showing the strand coming out of it.

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When aggregated, they make the clumps.

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Those strands appear to be composed of long-ish segments, whereas the other strands are beaded. Nothing is moving.

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