Octopus - how does one tell one species from another?

[Puffer Fish]

I have a fair number of Octopus pictures. Most are the common octopus, and very easy to ID when large. But small ones are a very different story.

In the last few weeks, have gotten images of what are obviously very different ones, but don't have a clue which they are.

This one was taken last year, it is about 5 inches long:

This one is about 4 inches tall from this last weekend:

Both are off of Destin, fl in around 80 ft of water.

On the second one, regardless of what color he(her) changed to, it's breathing tube (whatever the thing is called) stayed yellow colored, the first one was capable of changing all it's body.

I have better images of the second one, but tried to pick one with the eyes sticking up like the first had.

You can see that here:

This is from two weeks ago, and this one is about 3 inches long:

I have a blurry image of it moving away, and it is not even capable of the extended eye thing.

So, experts in all things slimy, what do I have here?

 

[Puffer Fish]

Not getting a huge number of responses... what a surprise.

My guess is that the bottom one is a very, very young common that has a lot of growing to do.

The top should be a pygmy or the other one that looks like a pygmy, but isn't and the middle one is any one's guess, but most likely a species that has not been id'ed.

But those are just guesses.

 

[SkimFisher]

I usually just ask

 

[Sully3]

The first one is a common octopus, the second looks like the Caribbean two-spot octopus, and the third actually looks like a pygmy octopus. Im not an expert, but Im pretty sure that's what they are

 

[Puffer Fish]

The first one is a common octopus, the second looks like the Caribbean two-spot octopus, and the third actually looks like a pygmy octopus. Im not an expert, but Im pretty sure that's what they are

Interesting.

Two-spot does have a rougher exterior, but from the images I can find, nothing on the level of this guy. It is also missing the spots. I got about 15 images, with it changing colors a couple of times and there is no spot of any kind.

Here is similar octo from last year... again about 4 inches in size:

I should point out that these were both taken in about 80 ft of water, around 10 miles off shore.

The little tiny short arms on that last one bother you at all? At that size, it should be an adult, with very long arms.