Common name : nautiluses

Aspect : rounded, smooth with a white underside and striped with brown bands above; the shell is coiled in a flat spiral and cut into about thirty "chambers" (camerae) separated by partitions (septa) which are crossed by a conduit (siphuncle) which regulates the buoyancy; the innermost partitioned part of the shell is called the phragmocone; the animal's body is in the last chamber; average size between 10 to 25 cm

Feeding : slow-moving opportunistic predators and scavengers (hermit crabs, lobsters, small fish, carrion, worms, ...)

Environment : Indo-Pacific region (Philippines, Indonesia, Papua New Guinea, Northern Australia, Fiji, Solomon Islands, and Western Pacific); at daytime they migrate deeper (300–700 m) to avoid predators and bright light but at nighttime they ascend to shallower depths (90–150 m) to feed