Sorry about the delayed response, I had to do a little research on this one...
is currently accepted as a cranchiid, and of the following characteristics, the ones we looked at checked out.
Cranchiids are characterised by the following:
- Mantle fused with the funnel and head in the occipital area (yes)
- Buccal membrane with six lappets (DDVV) (yes)
- Photophores present on eyeball (several round or 1-2 elongated) (yes)
Also (the theory goes): "Characteristic to the family is a spacious closed body cavity (coelom) containing a considerable quantity of NH4Cl solution. Density of this solution is lower than sea water, so the coelom serves as a float that maintains the squid in a state of neutral buoyancy ('bathyscaphoid squids'). A horizontal membrane divides the mantle cavity into an upper (containing the coelom) and lower part communicating by two round openings - the spiracles, located above the gills; the respiratory flow of water passes posteriorly along the upper chamber on both sides of the coelom, then through the spiracles, over the gills,forward to the head and out through the funnel." (Nesis 1987)
We don't know anything about Mesonychoteuthis
' buoyancy yet, and we do know that the insides of this specimen are considerably damaged.
I also found this on Tree of Life: "The ability of cranchiids to maintain the digestive gland in a vertical orientation can be seen the the adjacent photographs." (See this page
and this page
So... I think it's the digestive gland that's vertically oriented (half within the coelom, half outside), but just the coelom in general that encloses the NH4Cl. And on a side-note, that Taonius
is one of the freakiest
-looking squid I've ever seen.
I know I
learned something new today...
Nesis, K.N. 1987. Cephalopods of the world
(English translation). Tropical Fish Hobbyist (T.F.H.) publications, Neptune City. 1–352.