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British Marine Life Study Society

  Beadlet Anemone
 
Beadlet Anemones
Common Name(s):
 Beadlet Anemone
Scientific Name:
 Actinia equina
Family:
Usual Size: 
    25 mm
(base diameter)                                                     
                                                                                          Photographs by Andy Horton
Identification:
Colours: red, green, brown. 

The blue beads (acrorhagi) are always present at the top of the column underneath the tentacles. Occasionally they are white or off-blue. 

 The green variety is sometimes known asActinia prasina.

Similar species: Actinia fragacea , Anthopleura ballii



 

Beadlet Anemones
 Actinia species

Gallery of Beadlet Anemones on the NE Atlantic Cnidaria facebook group.
Click on the images for the gallery of original photographs

Group members are encouraged to upload their own images of this very common intertidal sea anemone to the group portolio..The Beadlet Anemone is found in a small variety of colours and patterns that some people have divided Actinia into two or more species, notably the all red or green Actinia equina and  the 'strawberry variant'Actinia fragacea with a red column speckled with green spots. The variations are further complicated by striped specimens and brown specimens which may look orange in certain light.There are still mysteries over the reproduction of this anemone which have not been resolved conclusively. 

Actinia equina on MarLIN
BMLSS Sea Anemones



6 February 2012
The Beadlet Anemone, Actinia equina, collected on Worthing Beach on 18 April 2011 is now a "strawberry type" with pale tentacles which is frequently seen in wild specimens. It has a reddish-brown column with a full array of green spots. 

22 October 2011
The Beadlet Anemone, Actinia equina, collected on Worthing Beach on 18 April 2011 and recorded immediately below, has now developed into an immediately recognisable as a "strawberry type" Actinia fragacea, after six months, but not a bright crimson as a "classic" specimen:  the column is dark brown spotted with small green spots, the tentacles are now a light crimson. 

19 May 2011
A large plain green specimen of the Beadlet Anemone, Actinia equina, collected on Worthing Beach on 18 April 2011 suddenly diminished in a manner seen before in the Actinia sea anemones. The green specimen with a basal diameter of approximately 60 mm and a larger tentacle span shrivelled up into a smaller version that looked as though it might be dying, and the tentacles became thinner than those of the Snakelocks Anemones, Anemonia viridis, and the oral disc disappeared from view covered by the partially retracted tentacles. On 20 May 2011, I noted that sea anemone had returned to its normal appearance. On 21 May 2011 I noticed that its column was covered in spots which were pronounced enough to be nearer in appearance to the designated species Actinia fragacea. Its spots were distinct light green but the background colour of the column became brown rather than red. It was slightly smaller with a basal diameter of about 50 mm. Intermediate forms or Actinia equina with green lines and spots are known to occur occasionally. This anemone has green tentacles whereas the usual "strawberry type" has crimson or red tentacles. 
 

Breeding: 

Viviparous.  Young approx. 12 -100 


 Beadlet Anemone, Actinia equina, spurting out a young anemone.

The best explanation of their reproduction is by parthogenesis. However, the author of this piece (Andy Horton) considers the likelihood that they break off internally (a bit like internal basal laceration) to be a possibility. No evidence of sexual reproduction has been observed despite extensive study. 

Beadlet Anemones are either male or female, but it is not yet understood if sexual reproduction occurs. Both sexes are known to brood offspring internally before giving birth to live young. It is thought that the offspring are produced asexually by a process of internal ‘budding’.   (Fish & Fish and verified by personal observation).

Spring 2000: You remember the big Beadlet you gave me ages ago ? Came downstairs this morning and found it has literally exploded...there are hundreds of tiny anemones everywhere in the tank, all over the parent, the rocks, pumps..they are everywhere. I've never seen one do that before, the other ones I've had have normally given birth to a few at a time, not like this one. The parent seems to be OK, a bit shrunken and lumpy, but otherwise fine

Beadlet Anemone with lots of babies about to spurt out (July 2003)
Photograph by David Hallett via the Wet Thumb Smart Group


Habitat:
Intertidal. 
 

Beadlet Anemones
                            with their tentacles retracted.
Beadlet Anemones with their tentacles retracted.
Food:
Mussel flesh, small crustaceans (copepods, larvae), fragments and whole larger (dead) crustaceans, worms. Small crabs, especially the Shore Crab

Biogeographical Range:
NE Atlantic, Arctic-tropics (salinity over 2.8% only, absent from the Baltic). 
Temperature range 2º C - 28º C. 
Bionomics: 

Additional Notes:
In captivity, this anemones has been changing colour, over a long period of time (about one month). The notes have been lost, but the anemone either changed from red to green through an intermediate brownish stage or vice-versa. 

Sea Anemones fight over territory. The red Beadlet Anemone, Actinia equina uses its acrorhagi (blue beads) and the green Snakelocks Anemone, Anemonia viridis uses its long tentacles. pic.

Double-headed specimens can occur

Neither "catch tenctacles" or acontia have been observed in this species. 

"Sir John Dalyell at his time kept a well-known specimen of Actinia equina named "Granny" in captivity for decades and at his decease Charles Peach inherited the animal, which in this way happened to live in Edinburgh for more than 50 years, so at least certain species seem to be able to have a very long potential life span." 
(from Hans.G.Hansson@TMBL.GU.SE **** Tjaernoe Marine Biological Lab. ****
http://www.tmbl.gu.se   Phone: +46 526 686 36   Fax: +46 526 686 07
Personal home page: http://www.tmbl.gu.se/staff/HansGHanssonP.html  )

More Information Link

Time lapse of the anemone crawling (External site) http://www.nhm.ukans.edu/~inverts/

Stripes occur on both red and green specimens. The blue acrorhagi can be seen clearly in this Sussex specimen. 

Information wanted: Please send any records of this sea anemone, with location, date, who discovered it, how it was identified, prevalence, common name and any other details to: 
Shorewatch Project EMail Glaucus@hotmail.com. 
All messages will receive a reply. 
 
Shorewatch Project

Cnidaria Web Site (World)

 

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