This looks like Chrococcus sp

Thanks for your answer

@ AZIZ AHMED and sir this one

Try Anabaena.

ya it look like Anabaena but i have isolated from marine habit but literature tells something else its fresh water

Dear, Priti, I agree with Dola，it should be Nostoc or Anabaena .

The picture is of poor quality, but I would suggest a green coccoid not a cyanobacterium. Make an absorption spectrum, either in vivo or on the extracted pigment so as to exclude or include a cyanobacterium

Dear Priti:

I agree with Laura, I think that your first picture shows an unicellular taxon with chloroplast and pyrenoid, thus it is not a Cyanobacteria. It could be a Chlorococcaceae, proof staining with lugol. It would be very important to have a scale.

The taxon showed in the second picture is filamentous and as it was mentioned it is probably a Cyanobacteria, I can not see the heterocyst thus it is not possible considering the taxon is a Nostocaceae.

Good luck with the determinations. Eugenia

I agree with Sar.