A specialize cell unique to the phylum Cnidaria. It contains a capsule-like organelle housing a coiled thread that, when discharged, explodes outward and functions in prey capture or defense.
The unique cephalopod mollusks can be found in the Indian and Pacific Oceans, living in rock crevices and coral reefs. Several characteristics make the nautilus stand out from other mollusks and marine animals. Unlike other mollusks, the nautilus has a hard external shell, which takes the form of a spiral.As the animal grows, it seals off chambers in the shell which fill with gas, making the shell buoyant so that the nautilus can swim.he beauty of the nautilus shell has inspired many beach-oriented establishments or brands to name themselves after it. One example is the Nautical Hotel in Santa Teresa, Costa Rica. Though the design of the hotel itself bears no resemblance to the nautilus shell, the name conveys a sense of paradise.
Physical description. Chocolatey-brown zebra stripes adorn the nautilus's smooth, white shell. It expands its living space as it grows, adding internal chambers in a perfect logarithmic spiral coated in mother of pearl. The body is situated in the last chamber, and about 90 slim tentacles and a large eye peer out.his animal usually lives where the slopes of coral reefs descend into deep waters. During the day, it resides in dark cool waters at depths from 900 to 2,000 feet and ascends to shallower waters (300 to 500 feet deep) at night to feed.