Amicrobe is discovered living in an extreme environment near a deep sea vent. the microorganism lacks a nucleus and peptidoglycan in its cell wall, but it does have unusual membrane lipids. this species is most likely a member of the domain

Archaea

Explanation:

Archaea are prokaryotes, which means they lack a nucleus. Many Archaea are extremophiles, organisms that live in extreme conditions, which give us another hint. But most importantly, a unique characteristic of Archaea is the presence of ether linkages in the lipids of their cytoplasmic membranes. This  distinguishes archaea from eukaryotes and most bacteria.

the atm that sounds like it should be the answer