Context: Another non-obligate symbiosis is known from encrusting bryozoans and hermit crabs that live in a close relationship. The bryozoan colony (Acanthodesia commensale) develops a cirumrotatory growth and offers the crab (Pseudopagurus granulimanus) a helicospiral-tubular extension of its living chamber that initially was situated within a gastropod shell.

Question: What type of symbiosis seen between bryozoans and hermit crabs?
Answer: non-obligate

Question: What species of crab has a helicospiral-tubular extension of its living chamber?
Answer: Unanswerable

Question: What species of crab develops a cirumrotatory growth?
Answer: Unanswerable

Question: What relationship is it considered when the bryozoans and hermit crabs do not live in a close relationship?
Answer: Unanswerable

Question: Where is the cirumrotatory growth in the crab located?
Answer: Unanswerable