Colonial Algae -- Gonium? Eudorina?

[billporter1456]

Ran across this a day or so ago and wondered if these pics would allow identification.

[Olympusman]

Yes, the ones in the mucilage envelope appear to be Eudorina.

Mike

[carlos.uruguay]

Nice images
Watching cell junctions seem Gonium. Without security

[billporter1456]

Thanks, Mike and Carlos! I am now thinking it may be Platydorina because the group of cells seemed fairly flat rather than spherical.

[actinophrys]

Actually I think this is Pandorina, though it is not the usual packed form. Instead you can see the green spheres aren't single cells but round clusters, so this is really a colony in the process of division. That rules out types that only form flat regular colonies like Gonium, or where some anterior cells do not reproduce like in Eudorina.

Compare for instance some pictures of dividing Pandorina from the Protist Information Server or by Dr. Wagner; the parent colony becomes more open while each cell divides into a new packed one. This is what earns them their name, for mythical Pandora, literally "All-giving".

[carlos.uruguay]

Very interesting!

[billporter1456]

Actually I think this is Pandorina, though it is not the usual packed form. Instead you can see the green spheres aren't single cells but round clusters, so this is really a colony in the process of division. That rules out types that only form flat regular colonies like Gonium, or where some anterior cells do not reproduce like in Eudorina.

Compare for instance some pictures of dividing Pandorina from the Protist Information Server or by Dr. Wagner; the parent colony becomes more open while each cell divides into a new packed one. This is what earns them their name, for mythical Pandora, literally "All-giving".

Very cool! Thanks for your very informative reply. I looked at the images you suggested and have become convinced that it is Pandorina. Maybe this explains why it appears that there are more than the two flagella per cell one might expect. (The flagella are more easily seen in the video than in the still images.) Thanks again and I'll post a link to my little video when it is completed.