Yes friends, blue ring octopus. I know there exist 3 species:
H.fasciata ( my favourite)
H.lunalata
and H. maculosa

But yesterday I have seen another specie ( I can't find now the web page, sorry), it has the blue rings in a middle sice between H. lunalata and H.maculosa. What specie is it? there exist other species?

Cheers
Carles

found a mention here

http://animaldiversity.ummz.umich.edu/site/accounts/information/Hapalochlaena_lunulata.html
H. nierstraszi

H. nierstraszi is a disputted specie. Has anybody,a picture of it?

H. nierstraszi, as far as I know, only exists as a preserved specimen from the Andaman Islands. There are several undescribed species. I have posted photos of one from Lizard Island and there is another very similar to H. lunulata in Lembeh. Norman also has photos of several undescribed species from Australia.

Roy

I thought (from my brief reading of Cephalopods of the World) that there were loads of species of Hapalochlaena making it very difficult to tell the difference , and they were just numbered 1-5(other than the ones mentioned). It looks like they have only very recently speciated- I wonder if they can interbreed at all?