[Octopus]: Espy - Abdopus ?

Far more complicated. I have the arm of Monty preserved in alcohol (the rest is in formalin) just in case I find a student that would like to try a DNA match or DNA registry. Kat's PHD research focused on reidentifying a genus of squid (now proudly called Callimachus :biggrin2:). One of the complaints I have is that we can't easily obtain full official descriptions of animals. A lot of the identification requires disection and knowing what you are looking at and then researching to find a match.
 
DWhatley;180806 said:
Far more complicated. I have the arm of Monty preserved in alcohol (the rest is in formalin) just in case I find a student that would like to try a DNA match or DNA registry. Kat's PHD research focused on reidentifying a genus of squid (now proudly called Callimachus :biggrin2:). One of the complaints I have is that we can't easily obtain full official descriptions of animals. A lot of the identification requires disection and knowing what you are looking at and then researching to find a match.

So how exactly would one go about 'discovering' a new species? Does it need DNA mapping? I've become rather interested in this lately after hearing that a single scientist had gone on a deep sea trip and identified dozens of species. Some of which I was sure I'd heard of before.
 
Well, let me tell you what's been going on at the Smithsonian:

There's a new species of finned octopus, and since I don't know whether they want to release the information about this or not yet I'll call it Finnoteuthis sp. A, which is still being sussed out in terms of how it's related to the other, er, finnoteuthids. DNA evidence doesn't match up well with morphological evidence right now and the species picture is clearer after more genes are used, but it's still inconclusive. Sometimes it seems like more of an art than a science to figure out where a species belongs.

The best I can say from what I know is that it is Very Very Difficult.
 
Once there is a release on finnoteuthis it would be great if you would present a page on the different avenues used to identify and isolate a species from your prospective. Most of us don't get close to the process and have no clue what is involved. I know the write-ups are easier to get for university folks but just trying to find an official definition when you know the species you are looking for is almost impossible for the average aquarist. One question you might be able to answer though, how many animals need to be found to be able to attempt to classify a new species?
 
Well, technically only one is necessary. However, it's a good idea to have more. There are only two known specimens of sp. A. You usually need a holotype and it's usually a good idea to have one or more paratypes. There are also, in place of holotypes and paratypes, syntypes and lectotypes (although in practice, I don't know how a lectotype differs from a holotype).

More animals decreases the chance that you're misclassifying it.

I refer you to the SI decapodiform cephalopod key; it has a lot of information on characteristics used to classify decapods. Invertebrate Zoology

Tintenfisch could probably answer this better than I could.
 
I started an identification reference in the biology forum and posted a copy of the link as the first entry. This is the kind of thing I would like to do for about 10 commonly kept species but at the hobbiest level looking at an alive animal so the questions will be different but the concept is the same.

Since we frequently have students intrested in ceph studies, your impressions as you learn to identify and the tools (and guesswork) that go along with the learning process would benefit new students as well as educate those of us with interest but who will never get behind a microscope. Entries in you blog as you get the hang of it would provide an interesting vicarious experience.
 
You develop heuristics for identifying cephalopods that are sort of shortened versions of the keys. If you look on the TOLWEB pages, you'll notice that the definitions for 'oegopsid' and 'myopsid' and 'sepiid' and 'sepiolid' are more complicated than a person's probable usual definition - for 'oegopsid' and 'myopsid' I think 'does it have a cornea?' (there's a problem considering the bathyteuthoids are in a different suborder altogether) and for 'sepiid' and 'sepiolid' I think 'does it have a W-shape pupil and a cuttlebone?'

Between squid families, you learn to look for certain characteristics: fin shape, mantle-locking apparatus shape, hooks, photophore shape, and a lot of others. I could probably reliably tell the difference between an onychoteuthid and a non-onychoteuthid that had hooks. It takes a lot of experience to know.
 
I've seen those color patterns in individuals as small as 19 mm ML, so it's definitely possible both this and Espy are A. aculeatus. If they are then this means you both got a good deal- at 25 mm ML they're not even ready to mate yet, so could be around for quite a while (relatively speaking). Espy's arms are a little on the short side in the pics, and the color patterns slightly different, so I'm not as confident. But the video looks like aculeatus. So hard to tell for sure.
 
I have the distinct feeling (and I have been trying to define how I "know" to be able to use it in my TONMCON ID talk) that Espy is an adult and not a juvenile and is why I think it is something other than aculeatus (abaculus fits his acclimation colors and size but he exhibits much more dark brown now, often body brown and arms white). His hectacotylus is quite well defined and, for once, I can see the arm channel clearly in spite of the tiny arm size (so I will challenge Roy on the ease of spotting the channel saying it is species related). I will (hopefully - I have not looked at the photo session results) post more photos tonight and look for the mosaic white spot pattern.

Also, I notice a "frilly" look on the suckers in Norman's view of abaculus and I noticed this same effect on Espy tonight. Is this a shared trait?
 
After looking at him stretched out, Espy's arms are too equally sized in girth and length for aculeatus so the species hunt continues.

He has stopped staying on the walls and is much less "friendly". I am taking this as a very good sign since he now hides and roams the LR hunting. I would be getting comfortable with being able to keep him awhile but he is not eating anything offered by hand and has not touched the hermits. He appears to hunt so I am hoping his small size means small foods and that he is consuming enough pods to satisfy his needs. The last two days he has only come out of his LR den (up inside a rock) only a little when we have been watching where he had been more actively searching the LR earlier this week. I am hoping that means he has eaten and not hungry but I don't like not being able to see his color (which has been very good)to get a feel for his health.


 

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Friday AM Espy was grey and wadded up on the sand in the front of the tank (when not out hunting he would den up inside a piece of LR, not out in the open). I put him in a floating hatchery to die unmolested before I went to work and he was dead when I returned. He never ate anything dead or alive offered. After a week I would see him hunting in the LR but never saw him appear to be eating anything (no hunched up, I have something in the middle of my webbing look). I added a large quantity of pods in hopes he needed tiny food but I would see them scurry out of the holes he was prodding, untouched and with no attempt to catch the ones that ran across his arms. Either this species eats something unusual or he was already senescent and had stopped eating naturally. I believe he fully acclimated to the tank at about two weeks, noted by a natural hiding and foraging behavior vs clinging to the glass and appearing to socialize.

Unfortunately, I forgot to photograph him before putting him in formalin :old:. From tip of mantle to tip of longest arm I would guestimate he was only 5-6 inches long with a mantle no more than 2" in circumference (no bigger than the first joint on my pinky finger). I feel certain he was an adult from his coloring and behavior. Looking through Norman's Cephalopods A World Guide this would put him in the range of the abaculus. Espy could show a white patterning but often demonstarted colors and patterns much like the Australian capricornicus (pg 239).
 

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