Unknown Squid from 2004. Any new info since then?

Mar 29, 2018
Washington State U.S.
Hello all!

I was prompted to try and ID this squid from a reddit thread on r/squid. This is a photo of the squid that was taken by NOAA in Operation Deep Scope back in 2004.
mysterious squid.jpg

I have seen the image circulate the web over the years, but I don't know if anyone has been able to identify it since the image came out. This sounds like just the thing that would of been discussed on this website in 2004. I found the original video of the squid: Video of squid

(Source for Operation Deep Scope 2004) This is the mission that captured the video of the squid.

The squid was filmed in the Gulf of Mexico at 1,600 feet deep. Here the scientists at the time identify it as a 6 foot long squid from the Mastigoteuthis genus. Interestingly though, in a future article from the same NOAA website a year later, the writers say that the squid was unidentified to science to the point of it's family being unknown (source). This leads me to believe that either A) the scientists went back on their identification; or B) The writer of the newer article didn't fully read the previous one. I think that both of these options could be likely, but it was never updated, and I would think that something like that would be caught and fixed.

This is a list of possible ID candidates that I came up with using Cephalopods of the World:
-Mastigoteuthis spp. (If the scientists are correct, it would be a new species as none currently discovered to my knowledge, emphasis that I am not an expert, get to that size and live that deep in the Gulf of Mexico)
-I couldn't find any known squid in the book that lives in the Gulf of Mexico that is known to get to that size at that depth with the shown characteristics.

List of squid that look similar, but I don't think entirely match:
-Architeuthis dux (I think the fins from what we can see are too triangular to be A. dux fins. Plus this specimen's small size for A. dux, but not entirely impossible. Mostly it's mantle to arm length ratio seems a little small)
-Illex coindetii (Too small even though it's rough body shape almost looks right. It also hasn't been seen at the depths reported for this squid)
-Ommastrephes bartramii North Atlantic Variation (Mantle grows to the right size, but arms and tentacles might be too short. Also specifically avoids the sea floor)

So does anyone here agree with the original ID? Do you think a different ID would be a better fit now that we know more about these genera? Interestingly enough, an E-jelly was used to attract it (or the bait next to the e-jelly). I didn't know that this lure idea has been around for so long, as I only heard of it in 2013 due to it being used to lure an in situ Architeuthis dux.

Now that I think about it, my search above doesn't detail squid that aren't found in the Gulf of Mexico, yet the squid in the image looks similar to squid such as the Purple Back Flying Squid from the Red Sea or the Humboldt Squid from the Pacific Ocean, but I feel that this body form is pretty common for squid that fill that niche (large, pelagic predator, deep sea), and it looks like this squid could fill that niche too.

Sorry for the oddly formatted post. I kept going back to different parts and revising it as I learned and researched more, and now I can't tell if my post is coherent or not.

Edit: I realized the title is still using 2005 as the date as I at first thought the image was from 2005, but I never changed it when I learned it was actually from 2004. Whoops... [ADMIN EDIT: fixed that for you!]
Last edited by a moderator:
was discussing this on the corresponding reddit thread and it looks like the most recent theory put forth in a paper here was that it was promachoteuthis sloani
Showing how long TONMO has been around, here is the classic thread on this!
Upvote 1
Idioteuthis is the largest mastigoteuthid.
So that would be a safe bet. The proportions still concern me, but lighting is a factor.
Upvote 0
was discussing this on the corresponding reddit thread and it looks like the most recent theory put forth in a paper here was that it was promachoteuthis sloani
Upvote 1
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