Please help me ID these critters

[pwnell]

They all were from either fresh or marine water.

[Charles Krebs]

Waldo,
I'll leave the first two diatoms to the diatom experts.

The third image looks quite a bit like a species of Mallomonas. But normally the chloroplasts "fill" the body.

The fourth looks like Acanthocystis.

The last looks like Pleuronema. (A similar looking but much smaller creature, <30micron, is Cyclydium)

But by all means, do not count on my ID's!

[rjlittlefield]

And one more, left side of the fourth image, looks like Spirogyra. (But don't trust me either! )

--Rik

[pwnell]

Thanks for the IDs. My "Pleuronema" is about 65µm long.

[jc maccagno]

Hello Waldo

We are almost neighbors!

Agree with Pleuronema with feeding membrane up
Spirogyra + Acanthocystis Agree that first 2 are diatoms Can't help you with the remaining one.

John

[carlos.uruguay]

Hi.
The second picture probably diatom Cocconeis
A greeting
carlos

[Ferry]

Number 4 is Acanthocystis turfacea, a helizoon.

[uaalgae]

The third image is indeed Mallomonas and it was in stress. This resulted in the formation of a resistant cyst called a statospore. This is a unique spore and found only in the Chryophytes. The statospore wall is siliceous and has a small pore at one end. If you look at old Dinobryon colonies, statospores are very common. Related to the diatoms.

My name is Donald W. Ott and I am a professor at the Uni. of Akron. My field of study is phycology and I am the microscopist in the Department. My YouTube name is uaalgae and I have been placing movies on the system for several months. I have seen marvelous and wondrous things![/i]