Would you pl add some more photographs? Close views.

As said by Ahmed pl. add some photographs  with anatomy of the thallus ( both TS and LS).  But i am thinking it is not seaweed may be animal. 

Its looks like some kinds of Hydrozoa

You'd better make some close up pictures

I'm not an expert of seaweed but I agree with Geddada Mohan Narasimha Rao it looks like an animal, perhaps an hydroid. would you pl. add some photographs with a closest view?

It looks like kelp or Jania but requires more close photos for confirmatory identification.

It is not all Jania, better to take cross section of the speciemen for proper identification, further I have collected this type of spccimens during the collection of seaweeds in the intertidal rocky surfaces of East coast of India. In general I have noticed this specimen in infra littoral fringe zone of the intertidal rocky surfaces along with Gracilaria, Sargassum and Spongomorpha. Thank you

ill add some more pictures asap. thanks for all your response.

Jania has no woody stem that is longer to that magnitude, and because of that; I suggested two options and requested for more closely taken photos for confirmation.

Albin, It  is not Jania  but it could be an animal  mostly a  hydroid

some more pictures. i could not manage any ls or ts of good quality. 

It is Hydroid but you can't identify the species without a good closeup on single polyp!

Good luck

Of course Razy. We need sjngle polp close-up photos.

look like coralline algae to me. is it fragile?

@ Gilan- it is not fragile. the structure is really hard.

Dear Jose, morphology is not only criteria for identification, why don't you take a cross section for proper identification. Still i am thinking is an animal rather than seaweed.

Thank you and all the best 

It  is more of a hydroid than an alga

I agree that it looks like an Hydroid (Leptothecata ?), but closer views are needed to see if hydrotheca and gonotheca do occurnad to see their precise morphology.