unusual octopus in Malta

Hey all, I found this guy yesterday on a night dive at Cirkewwa in Malta. He was out on open sand in about 35m and he was about 30-40 cm from arm tip to arm tip

It doesn't look like any octopus Ive ever seen here (we normally get the common octopus and the white spotted ones) and I can't find it in the basic i.d. book I have or on the net

It looked and behaved kind of like a mimic octopus but without the colouration

any ideas?

here's a close up

I wonder if it might be an Atlantic Longarm Octopus, Macrotritopus defillipi?

Cheers,

Jim.

He's beautiful! Amazing how large he can flatten his arms are... even wider than his head.

he really is beautiful and the way he changed shape as he moved about was really interesting

Jim I think you might be right. Do you know if the range includes the Med? Google mentions the caribbean

It is a "Octopus Macropus" or Atlantic White-spotted Octopus, White-spotted Octopus, Grass Octopus or Grass scuttle or Polpessa in italian.

There are not rare, but usually nobody dives deep at night so they are not very often spottet but a common victim of bottim fishing on sandy bottom during night.

What i did not know tiull now is that they can become almost transparent and this makes grechs pictures very unique!

http://en.wikipedia.org/wiki/Octopus_macropus

Chris

Hi chris thanks for the info but Im pretty sure it's not a white spotted octopus as Ive seen many of them (always at night) and this one was very different both in colouration - though as you say this can change - and in body shape since the arms seem to have a mantle-like skin flap all the way down whereas the white spotted octopus doesnt seem to have it to the same extent

Ive sent the pics to a local scientist working on alien species in Maltese waters and he seems to agree it's a Macrotritopus defillipi but he's checking on it. Ill let you know what he concludes

I don't think it is the polpessa either - unless a very young one. It does look like the atlantic long arm octopus - although I've only seen those in West Atlantic and also only during the day (plus they are not known in the Med). In reality the population of mimic's in Egypt are closer.

Ozaena cirrhosa is worth checking - as it is called white octopus in spanish. But I think the shape is wrong and colour is no guide in cephalopods.

I am pretty lost. I look forward to hearing what it is.

Alex

Seems to be some confusion about Macrotritopus defilippi. Octopus defilippi (Verany, 1851) was originally described from the Mediterranean Sea.

Mediterranean Collections

Sealifebase entry for M.defilippi

PDF from fao.org, see pg228

PDF Octopus defilippi raised from Macrotritopus

Cheers,

Jim.

hmm doesn't seem straight forward

My scientist contact confirmed it is an Atlantic long armed octopus and according to him it is in fact indigenous (as you say Jim) to the Med but it is fairly uncommon so at least Im happy to have seen it

Interesting info. Thanks guys. I didn't know that species was in the Med as it wasn't in any of my Med marine life books.

Alex

I found a reference in Wirtz and Debelius' Mediterranean and Atlantic Invertebrate Guide where it lists its distribution as including the Med and includes a photo of an individual taken in Crete which the authors say may be the first photo taken of the species in the Med. Makes me feel even happier with my photos since it seems it really is quite a rare sight locally