Translucent squid - how did this happen?

Steve O'Shea

TONMO Supporter
Staff member
Nov 19, 2002
With 'a few years' experience preserving octopus and squid (in museums) I'm used to things going to plan.

Attached is a pic of 'one of those specimens' that you would normally discard in a museum collection, because something 'went wrong'. What has happened is that the animal has gone quite translucent .... generally a sign of poor preservation (whereas all other specimens of this species, preserved during the same trip/expedition, look normal). The hooks on the arms of this small squid (an enoploteuthid) are intact, which means it isn't a problem with formalin solution buffering (they would 'dissolve' otherwise). So what happened? I don't know.

The reason why I ask is that the effect is quite interesting, in that beneath the micoscope the viscera is visible (as are the photophores on the viscera). Now if this procedure could be duplicated, just imagine what systematic characters you might see in larger-bodied squid (if they were treated in exactly the same way). I'd like to duplicate it. The problem is I do not understand the chemistry behind this quirk of preservation. Do we have any chemists out there that have any ideas how we could make larger-bodied squid transparent?

The only chemical that this specimen has been exposed to is formaldehyde; it was fixed in saltwater.

:shock: weird! I wonder about the protein content of the mantle muscle. If it was abnormal ( MUTANT) perhaps it's denatured or something and has thus an odd reaction to the formalin???????????????????????? :bonk: :bugout: :bonk: :bugout: :bonk: :bugout: :bonk: :bugout:


PS Keep in mind it took me two goes to get undergrad chemistry by the skin of my teeth

PPS I only did some biochem when I was forced to (screaming and kicking!)
.... we're about to test this recipe; check out the Fossils forum in a month-or-so; exciting things happening! Thanks again M!