Purple Octopus - using citizen science to discover marine interactions
This is the entity page showing aggregated messages and images for the named entity.

Balanus balanus

(Linnaeus, 1758)

George Brown I need help with the ID of this barnacle please. Found in a porthole on the V83, Scapa Flow, Orkney. Shell about 12mm high, water depth 12m.

Ian Smith Hi George I can rule out Balanus balanus and Verruca, but can't be sure what it is. Could you email me off-list a higher res version so I can zoom in?

George Brown Great news Ian, many thanks. I'll crop a RAW file. :)

Keith Hiscock Eve Southward can often give a view or suggest a contact - I will ask.

Ian Smith Hi George Thanks for high res. image. Balanus crenatus seems the best fit of the intertidal Brit. barnacles, ; deeply crenate aperture and shape of the overlapping insertion plates. The useful tergoscutal flap is not visible in your image. However, the postures of the opercular valves and extended cirri don't seem right for B. crenatus. A.J. Southward's Linn. synopsis shows a northern sublittoral sp., Chirona hameri, which is a reasonable match for the plates. Google images has several live pics of hameri by Erling S., and the posture resembles yours. I tend towards it, but can't give a definite id. I hope Erling or Eve (mentioned by Keith - a relative?? of A.J. Southward, deceased) will be able to help.

Ian Smith Have just noticed the red encrusted barnacle top right in your uncropped image above. What I can make out of the general shape is very like Southward's images of hameri; "half open tulip".

Keith Hiscock Eve Southward (widow of Alan) has looked at the pic (from all angles) and, although a barnacle 'expert' once removed, i.e. not a barnacle expert, can only suggest that it is a Balanus sp. I suggest not B. hameri (I have memories of them in the tanks at Menai Bridge). Check the spikey plates, ignore the opercular plates which are pushed-out. Could be B. crenatus, possibly B. balanus.

Andrew Want this photograph leads me to suspect B. crenatus... Just as a related point of interest: I recently came upon a massive specimen of Chirona hameri retrieved off West Mainland Orkney from a buoy at 45 metres depth - it was 63 mm from carina to rostrum (Southward's book has them max. at about 50)!

Message posted on Seasearch Identifications on 18 Nov 2013
Vasco Ferreira Anyone can help to identify this barnacle? It was taller than 3 cm, can it be Balanus perforatus? Many thanks.

Marco Faasse They look more like Megabalanus. Maybe more than one species is present. Check out M. coccopoma and M. tintinnabulum.

Erling Svensen Could be Balanus balanus? In Norway they grow to 5 cm.

Message posted on Seasearch Identifications on 27 Aug 2013
Animalia (Kingdom)
  Arthropoda (Phylum)
    Crustacea (Subphylum)
      Maxillopoda (Class)
        Thecostraca (Subclass)
          Cirripedia (Infraclass)
            Thoracica (Superorder)
              Sessilia (Order)
                Balanomorpha (Suborder)
                  Balanoidea (Superfamily)
                    Balanidae (Family)
                      Balaninae (Subfamily)
                        Balanus (Genus)
                          Balanus balanus (Species)
Associated Species