It could belong to Parmelia or some similar genus. However, for identification probably at least some apothecia will be necessary. I suppose, it will not be possible to identify this species from these photos.
I agree with Franz. The photographs can lead close to the Genus, but not the species. A meaningful identification at species level is possible only upon examination of the material by an expert. I suggested the name of Dr. G. P. Sinha because he has worked on lichens extensively in Meghalaya. If you have material, send it to him. Best wishes.
If those noted lichenologists will not be accessible, Dr D K Upreti, NBRI, Lucknow and his team are highly equipped with all these sort of Indian Lichens.