MAR-ECO Research Cruise

[Tintenfisch]

Here are some non-ceph but still very cool things. The first is what our catches normally looked like - the fish team would sort out their beasts first and pass the rest on to us. We pulled out all the cephs, ID'd and fixed them, and fixed the rest (crustaceans, jellies, salps, pteropods, etc) for someone else to look at later back on shore. The remaining photos are hatchetfish (also common), the barrel-shrimp Phronima (hollows out salps to live in, pretty cool), and a deep-sea ?viperfish caught mid-snack.

 

[DWhatley]

Interesting bright red shrimp. They look too bright to be peppermint shrimp but are they? Are there any shallow water cranchiids? Is the one with the green background still alive?

 

[bluespotocto]

How did you collect every thing? Did you dive?

Not sure where to match the name with the fish but what is the black fish with the little thing on his heads name? It looks like the fish from finding nemo!

 

[OB]

That Pterygioteuthis is marvelous, a "gem" indeed Relatively unscathed, considering the harvesting technique, but I take it the hatchet fish lost their tails that way?

 

[Tintenfisch]

These were collected with an Isaacs-Kidd Midwater Trawl (IKMT), which is pretty fine-meshed, a few hundred microns I believe. It was deployed either to the scattering layer(s) or to a set depth, usually 1000 or 2000m. Most of the stuff came in in pretty good condition, and many of the cephs were still alive (barely). Those we kept, if still active when caught, were gradually euthanized in ethanol before being fixed in formalin. By the end of the cruise, we got a few still-healthy individiuals from taxa we already had well represented, so we were able to release a few. I think the black fish is a kind of viperfish but I'm not sure... the Russians called it something else.
And there aren't any shallow-dwelling cranchiids that I can think of off-hand. I'll post a few more pics later today - there were some mighty strange-looking ones! Angel Perez, the other squid guy, mentioned that cranchiids are supposed to be the dominant ceph fauna in relatively nutrient-poor environments, which I found interesting. (And Meso might be an exception, as usual?)

 

[DWhatley]

Those are the darndest looking critters. A shame there are not at least some that could be kept in at least a public aquarium.

 

[Tintenfisch]

Here are a couple more cranchiids - first Liocranchia reinhardti and a close-up of its ventral tubercles, then Egea inermis (as best we could figure).

 

[Tintenfisch]

And these are Abraliopsis sp. (family Enoploteuthidae) with progressive zooms on the beautiful ventral photophores.

 

[DWhatley]

I just love those little cranchiids. Can you imagine an aquarium with several dozen zipping about with light catching their little opals? Or a huge night lit tank with hundreds. It would so get the attention of visitors.

Don't ask why my mind works this way but driving home from my interview the following decomposition of "Home on the Range" came to mind as I was thinking of your seafaring adventure:

Oh, give me a ride
to the octopus side
Where the squid and the nautilus play

Where bubbles are heard
instead of a word
And the sea remains tranquil all day.

 

[monty]

ventral tubercles? What are those for? Or are they just an anatomical feature for which the physiology isn't known?

 

[sorseress]

Some great photos! Fascinating stuff.

 

[Tintenfisch]

ventral tubercles? What are those for? Or are they just an anatomical feature for which the physiology isn't known?

Well... they're very handy for identification purposes... but I'm not sure whether their function (if any) is known; good question. They're the hallmark feature of the subfamily Cranchiinae.

 

[Tintenfisch]

Hi guys! Long time quiet on this material - sorry. I just started a new lecturing contract at AUT, half teaching, half research. So, finally back to working on the MAR-ECO stuff. I just checked all the cranchiid IDs and come up with a few things we didn't realize we had - Taonius (craziest eyes of any squid!) and Megalocranchia, among others. We decided to do some closer investigation of the cranchiid fauna, specifically looking at the tentacle clubs using SEM, so thought I might post a couple of the nicer shots here.

 

[DWhatley]

In the second SEM, what are the tiny drawn-up anemone looking things lining the sucker? Is that a genetically misplaced one on the right side?

 

[Tintenfisch]

Those are (creatively) called 'pegs' and they are part of the tentacular sucker ring armature in young squids of many families. I think they were first reported by Degner (1925), and they have been examined in detail by a few authors, notably Nixon & Dilly (1977, see ref below). Their function isn't entirely understood but they may improve the sucker surface's adhesion. In onychoteuthids, some of the suckers like this develop into hooks and the portion with the pegs is lost entirely, but while the suckers are in this stage, the arrangement and number of pegs seems to be a useful character for telling paralarvae apart (see attached photos).

Nixon, M. & Dilly, P.N. 1977. Sucker surfaces and prey capture. Symposium of the Zoological Society of London, 38, 447–511.