Looks like a branching coral (with a cross section through some of the branches), which would make sense for limestone.

Hi. They seem to be algae showing shallow waters. if you see many bioclasts then your paleoenvironment is probably shoal.

Polla:

Size, shape and visible features points toward algal bodies.

Best

Syed

It is coralline algae in shallow tidal  depositional environment

Hi Polla,

Your specimen might be a Spinaxon potyi sp.

Kind regards

Hakima

Thank you all for your recommendations.

Dear All

Thank you for your help! Our paper is now published.

(A new organ-species dasycladalean green alga from Darbandikhan, Kurdistan, Iraq, September 2018, Arabian Journal of Geosciences 11(17), DOI: 10.1007/s12517-018-3840-8. Ioan I Bucur, Kamal H Karim, Hyam Daoud, Show all 5 authors, Polla Khanaqa.

Regards

Polla