View Full Version : Octopus rubescens, not GPOs
Nancy Aug 11th, 2004, 12:15am Jonathan Minton from the NRCC has sent some more photos of what were thought to be little GPO, but they're almost certainly O. rubescens, The Pacific Red Octopus.
Fine looking octos! Thanks, Jonathan!
Nancy
Jakxx Aug 11th, 2004, 12:22am I simply love the color this species displays. Anyone who says that they are "muddy brown" hasn't seen this pictures :-)
Beautiful :)
By the way... I've always wondered... WHAT actually is the front part of an octopus? (Is this even defined?) The part with the mantle (in this case giving it somewhat the appearance of a large "nose") or the opposide?
Tigerkatze_82 Aug 11th, 2004, 06:39am Nice pictures :D
@Jakxx, my german colleague:)
I think the scientific termini "cephalopod" and (in German) "Kopffueßer" indicate where is "front" (cephalo = head, pod = foot). Front is where the arms are and the rear is the mantle...
Hehe, funny to regard the mantle as a nose though. Never thought that way. As the arms origin from the area around the mouth of the animal, I sometimes see them (the arms) as some kind of "lips" and then it's obvious to me where's the "front"...
Have a nice day
TK :cuttle:
Jakxx Aug 11th, 2004, 11:46pm Yes I know about the "koffueßer" term, it's more like, which way does an octopus normally face when it is moving, thus which way does he normally look. Is there even such thing defined as a front?
In case of cuttles and squids it's quite easy to see which side is actually the front, but its harder to tell if you look at an octopus since they seem to move in both directions quite often. I don't really know if I got this right but maybe you already see where I was aming to with this question. :o
It's maw may face downwards, but the eyes are aranged horizontally so there must be something like front and behind, right? :-)
WhiteKiboko Aug 11th, 2004, 11:52pm you have to keep in mind that cephs, unlike us, regularly move more freely in three dimensions.... plus being more amorphous, up or front both mean a little less....
hate to geek out on you but didja ever see star trek 2? i think the whole 2d vs 3d thinking is quasi relevent.....
of course how much weight do my words carry :?:
Nancy Aug 12th, 2004, 12:33am Once you have one in your house, I don't think you have any trouble telling where the front is.
An octopus may be put together somewhat strangely, but it has eyes that look at you and almost always leads with its body, holding its body somewhat like a head. Hard to describe, I know. But an octopus also has lead arms, which are "in front". It uses one or two arms for much of its exploration.
Nancy
Jakxx Aug 13th, 2004, 10:31pm Yes, that was more the direction I was aiming at.. or more simply said, do octos have a favorite direction they move in? e.g. dragging it's mantle behind or pushing it forward into the direction it moves.
The eyes seem to be arranged in a way that it doesn't seem to matter which way the octo moves, unlike us humans. Walking backwards or sideways all the time simply isn't our thing apparently (or at least not mine :bonk:)
Nancy Aug 13th, 2004, 11:30pm I found when I looked at the photos I'd taken, the octopus was often seen from the "side" as it moved forward.
The octo leads with his eyes and the rest of the mantle follows behind, if that's any help.
I used to play a game with my bimac where I pressed my face against the glass, and my bimac did the same, on the other side of the glass. An octopus can swivel its eyes around and look at you head on, with both eyes. So Ollie and I were "face to face".
Nancy
tjohnson Aug 14th, 2004, 12:33am Very pretty redish-orange, I love it.
Nancy Aug 14th, 2004, 10:37am Since you liked those pics, here's another one!
Nancy
tjohnson Aug 14th, 2004, 12:41pm I need to get some of those barnacles that are in that picture, I've seen other people using those in thier tanks, and I think my lil guy (Crazy Legs would really enjoy them. Anyone have a source?
Nancy Aug 14th, 2004, 12:45pm I bought a big bag of them (around $10) from one of those oceanside shell shops in Galveston, Texas. They were called Goose Barnacles.
I've seen big clumps of them for sale in various LFSs, also ones made out of resin.
Some octopuses will hide in them - my bimac would not.
Welcome to Happy Legs!
Nancy
Jakxx Aug 19th, 2004, 02:16am Hm, I looked a little around and often the same pair of arms are refered to as "the first two" or "front two"
So basically the octopus has a "front" and "back".
this nicely shows in this picture here for example:
http://www.cephbase.utmb.edu/imgdb/images/Cb1434.jpg
Note that the octopus faces left although he is about to move towards the camera sideways, one eye leading the body. So the opposide of the mantle has to be the front part :-) Although I think most pepole who see this picture would say that the octopus faces right. It just looks more natural to most people, but when you consider the position of the beak, it all makes sense that he actually faces left :-)
Most octos don't really seem to care though :P
Tigerkatze_82 Aug 19th, 2004, 03:16am This is what I was trying to say the other day :mrgreen:
TK :cuttle:
joel_ang Aug 19th, 2004, 04:47am I guess this goes to show how hard octopuses are to identify, even to the experts...
it wouldn't seem right for an animal which relies alot on vision for hunting and survival to have a large vision obscuring mantle in front of it would it?
Andy Lister Aug 28th, 2004, 12:21pm Nancy,
What are the differences between teh rubiscens and the GPO?? The photos look very similar to the last GPO I got from Living Elements. Is this a mistake that people can often make?
My GPO (?) died a few weeks back after me finding some eggs in the tank but was not all that big (about 150cm arm span) by the usual size i see them. Could I have had a rubiscens?
~Andy
Nancy Aug 28th, 2004, 12:55pm Hi Andy,
I think your octo was too big to be an O. rubescens.
They're hard to distinguish when they are smaller, and those whose photos I posted were still quite small. O. rubescens has a body of 10cm as an adult, arms to around 30 cm each, while, as you know, a GPO gets much larger.
The distinguishing features of O.rubescens are ring-like white markings. There are two pairs of these, one on the body and the other at the base of the arms in front of the eyes. These can be hard to see on younger octos.
I suspect that you had a smaller GPO - not all of them get so large.
And just a personal comment - a lot of people seem to get bitten by O. rubescens - I first encountered this in comments of divers. And sure enough, when I was visiting the NRCC, one of the little red octos bit Jonathan!
Nancy
Andy Lister Aug 28th, 2004, 12:58pm Fantastic, thanks Nancy!
I think he was slightly larger then wasn't he! Hehe
I got me a nice sweet little GPO now, around 75cm arm span... She needs a name!
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