(1) What is a halophile?
Answer: A salt-loving organism.
(2) What is a benthophile?
Answer: An organism which thrives at great depths.
(3) What is a psammophile?
Answer: A plant or animal which thrives in sand.
(4) What is a symphile?
Answer: A creature which lives in a nest of ants or termites, and is tended by them.
(5) What is a cryophile? (bonus: what is a thermophile?)
Answer: An organism which thrives at low temperatures (bonus: an organism which thrives at high temperatures).