Common octopus - Octopus vulgaris Lahinch Seaworld

Common octopus - Octopus vulgaris

	Octopus vulgaris recorded and expected distribution in Britain and Ireland
Basic Information researched by: Emily Wilson

Phylum	Mollusca	Molluscs e.g. snails, slugs, mussels, cockles & clams
Class	Cephalopoda	Cuttlefish, nautilus, octopus and squid
Authority	Cuvier, 1797
Recorded British Isles Distribution	Reaches its north-eastern limit in south-western Britain and the western English Channel.
Habitat information	Found on rocky coasts, shallow sublittoral. Has adapted to live in very different habitats
Description	A medium to large sized octopus with a distinctly warty body. The arms are thick and stout bearing two rows of longitudinal suckers. The colour varies from grey-yellow-brown-green and can change according to the situation.
Key identification features
Medium to large sized, body distinctly warty. Arms stout of about equal length and thickness with two longitudinal rows of suckers, dorsal pair of arms slightly shorter. Colour - variable, grey-yellow-brown-green according to situation.

Curled octopus - Eledone cirrhosa
	Eledone cirrhosa recorded and expected distribution in Britain and Ireland

Phylum	Mollusca	Molluscs e.g. snails, slugs, mussels, cockles & clams
Class	Cephalopoda	Cuttlefish, nautilus, octopus and squid
Authority	Lamarck, 1798
Recorded British Isles Distribution	All British and Irish coasts.
Habitat information	Found on rocky coasts, lower shore, sublittoral.
Description	A broad mantled octopus with a smooth or finely tuberculate body. The arms are slender, finely tapered distally and curled when at rest, with a single row of suckers. The colour is predominantly red-brown dorsally and white ventrally but species are able to change colour quickly to match their background.
Key identification features
Mantle ovoid, broad. Skin covered with very fine, closely-set granulations, interspersed with larger warts. Head narrower than body, one cirrus over each eye. Arms moderately short, suckers uniserial. A low, pale coloured ridge encircles the lateral periphery of the mantle. Colour - living animal yellowish or reddish orange to reddish brown dorsally with diffuse rust-brown patches, white on ventral surface.

A Curled Octopus has a single row of suckers. The Common Octopus has a double row.

Curled Octopus

Status: Common and widespread.

Description: The cephalopods (meaning 'head-footed'), a group of molluscs that contain the octopuses, squid and cuttlefish, are probably the most intelligent of all invertebrates. They have well-developed heads, with large eyes and mouths that feature beak-like jaws. All octopuses have eight tentacle-like arms; indeed 'octopus' derives from the Greek for 'eight-footed'. The curled octopus is typically yellowish or reddish-orange in colour with rusty-brown patches and a whitish underside; individuals are able to rapidly change colour to suit their surroundings The slender arms taper towards the tips; they feature a single row of suckers and are curled when the octopus is at rest, hence the common name

Range: Found around the British coastline; it also occurs in the northeast Atlantic and in the Mediterranean

Habitat: Inhabits rocky coastal areas.

Biology: Like all cephalopods, the curled octopus is an active predator. It usually feeds on crustaceans, molluscs and other invertebrates as well as fish. When feeding on crabs, the curled octopus immobilises its prey by puncturing its eye and injecting toxins into the body of the crab. The digestive enzymes contained in the saliva of the octopus break down the attachments within the crab's body, allowing the carapace to be easily removed

Conservation: Not currently threatened. Conservation action has not been targeted at this common species.