Archerd Shell Collection > Shell Classes > Cephalopoda > Nautilidae


Family: Nautilidae (Chambered Nautilus)


Description:
 
Unique among the cephalopods in having a shell, the nautilus is represented by four living species. In some ways it appears to be a relic, since seventy-five or more families of nautilus-like fossils can be dated to about 500 million years ago (Mya). The present day species, is believed to be somewhat different, especially as to its soft tissue anatomy, but the basic form has persisted.
 
Unlike other cephalopods, Nautilus can fully retract itself into the final whorl of the shell. Surrounding the mouth are ninety thin tentacles, which are retractile and without suckers. While carnivorous, Nautilus seems to be rather slow moving and not as intelligent as its more evolutonarily advanced cousins, squid and octopus. It lives at depths of 1,500 ft, coming to the surface typically at night, and it is found predominantly in the region between Fiji and the Philippine Islands. 
 
In the mid-sectional shell image at right, small holes at the midpoint of each chamber's partition demarcate the siphuncle, a shelly tube that connects the chambers. A vascular extension of the mantle penetrates the siphuncle, and gas (mainly nitrogen) can displace liquid within the chambers for buoyancy adjustment.

Classification:

Subclass:  Nautiloidea (Tetrabranchiata)
Superfamily: Nautiloidea

Family: Nautilidae

Single Genus
  • Nautilus pompilius (Linnaeus, 1758)
  • Nautilus macromphalus (Sowerby, 1849)
  • Nautilus scrobiculatus (Lightfoot, 1786)
  • Nautilus belauensis (Saunder, 1976)
Nautilus pompilius

NautilusShellSection.jpg (14784 bytes)Nautilus pompilius
Chambered Nautilus
14.3 cm. shell (upper image) & mid-line cross section (lower image)

 


SEE THE LIVE NAUTILUS
Dr. James B. Wood
The Cepalopod Page

Nautilus pompilius
Chambered Nautilus

 


Archerd Shell Collection > Shell Classes > Cephalopods > Chambered Nautilus