Archerd Shell Collection > Shell Classes > Cephalopoda > Argonautidae

Family: Argonautidae ("Paper Nautilus", Argonaut)

The family Argonautidae are not nautili; rather, they are very closely related to the octopus and also have a dibranchiate body plan. Not too much is known about these deep water forms, except that their thin, parchment-like, white shell is occasionally swept to shore (at right).  The shell is actually a cradle, which is not secreted by the mantle, but instead is secreted by the two dorsal arms of the female. It is used for the purpose of protecting the tiny eggs. The female is distinctly larger than the male. It may grow to a length of two feet, the male rarely being over half an inch in size.
Argonauts live in warm seas world-wide. Some have been captured at 3000 ft depths, but usually they swim nearer the surface.  They are occasionally washed ashore during storms.
Argonauta argo
Argonauta argo (Linnaeus, 1758)
Common Paper Nautilus
(a 14.0 cm egg case)


Dr. James B. Wood
The Cepalopod Page

Argonauta nodosa
Paper Nautilus

Class: Cephalopoda
Subclass: Coeloidea (Dibranchiata)
Order: Octopoda
Suborder: Incirrata
Family: Argonautidae
Major species in family Argonautidae:
  • Argonauta argo (Common Paper Nautilus)
  • Argonauta gruneri (Gruner's Paper Nautilus)
  • Argonauta hians (Brown Paper Nautilus)
  • Argonauta nodosa (Nodose Paper Nautilus)
  • Argonauta nouryi (Noury's Paper Nautilus)

Archerd Shell Collection > Shell Classes > Cephalopods > Argonauts