[2] Argonauta cygnus Monterosato, 1889 was described based on a shell which lacked these protrusions, although it is now considered a junior synonym of A. argo.

[2] A dwarf form exists in the Mediterranean Sea, which was described as Argonauta argo mediterranea Monterosato, 1914, although this taxon is now regarded as invalid.

[8] Eggs are usually laid when females reach 14–15 mm ML, although the size at which this takes place differs across the animal's range.

The authors found that about half of the animal's aboral surface was damaged and large pieces of mesoglea were missing, presumably removed by the argonaut.

[13][14] Observations of captive A. argo females suggest that the expanded webs of the dorsal arms may aid the animal in feeding.

Mark Norman mentions, "when food was touched against the spread webs, an arm shot out of the shell in a sweeping action, grabbing the prey".

In Japanese, this species is called "Aoi-gai" (kanji: 葵貝, Katakana: アオイガイ[15]), which means "Shell of Aoi" (not Malva but Asarum caulescens).